Lincoln Aviator Manuals
Lincoln Aviator 2020-2026 Service Manual / Electrical / Instrumentation and Warning Systems / Horn / Diagnosis and Testing - Horn

Lincoln Aviator: Horn / Diagnosis and Testing - Horn

Diagnostic Trouble Code (DTC) Chart

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices.
REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).


  Diagnostic Trouble Code Chart


Module   DTC Description Action
  BCM B1323:11 Horn Switch:Circuit Short To Ground   GO to Pinpoint Test B
  BCM B1323:11 Horn Switch:Circuit Short To Ground   GO to Pinpoint Test D
  BCM B1C55:12 Horn Relay:Circuit Short To Battery   GO to Pinpoint Test A
  BCM B1C55:12 Horn Relay:Circuit Short To Battery   GO to Pinpoint Test C
  BCM B1C55:14 Horn Relay:Circuit Short To Ground Or Open   GO to Pinpoint Test A
  BCM B1C55:14 Horn Relay:Circuit Short To Ground Or Open   GO to Pinpoint Test B
  BCM B1C55:14 Horn Relay:Circuit Short To Ground Or Open   GO to Pinpoint Test C
  BCM B1C55:14 Horn Relay:Circuit Short To Ground Or Open   GO to Pinpoint Test D

Symptom Chart(s)

Symptom Chart: Horn

Diagnostics in this manual assume a certain skill level and knowledge of Ford-specific diagnostic practices.
REFER to: Diagnostic Methods (100-00 General Information, Description and Operation).


  Symptom Chart


Condition Actions
The horn is inoperative
  • GO to Pinpoint Test A
The horn is always on
  • GO to Pinpoint Test B
The horn is inoperative
  • GO to Pinpoint Test C
The horn is always on
  • GO to Pinpoint Test D

Pinpoint Tests


PINPOINT TEST A : THE HORN IS INOPERATIVE- VEHICLES WITHOUT ADAPTIVE STEERING

Refer to Wiring Diagrams Cell 44 for schematic and connector information.

Normal Operation and Fault Conditions

REFER to: Horn - System Operation and Component Description (413-06 Horn, Description and Operation).

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
BCM B1C55:12 Horn Relay: Circuit Short To Battery A Continuous Memory Diagnostic Trouble Code (CMDTC) that sets when the BCM detects a short to voltage on the horn relay control circuit. The BCM disables the horn when this DTC is set.
BCM B1C55:14 Horn Relay: Circuit Short To Ground Or Open This DTC sets when the BCM detects a short to ground or an open on the horn relay control circuit

Possible Sources

  • Fuse
  • Wiring, terminals or connectors
  • Clockspring
  • SCCM
  • Horn
  • Horn relay
  • Horn switch
  • BCM
  • BCMC

Visual Inspection and Pre-checks

  • Verify the BCM fuse 13 (7.5A) is OK.
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
A1 CHECK THE BCM (BODY CONTROL MODULE) OUTPUT BY ACTIVATING THE BCM (BODY CONTROL MODULE) HORN_RELAY PID (PARAMETER IDENTIFICATION)
  • Ignition ON.
  • Using a diagnostic scan tool, view BCM Parameter Identifications (PIDs).

  • Access the  BCM  and control the  HORN_RELAY  PID

    and command the horn ON and then OFF.

Does the horn sound when commanded ON?
Yes GO to A10
No GO to A2

A2 CHECK FOR BCM (BODY CONTROL MODULE) DTC (DIAGNOSTIC TROUBLE CODE) B1C55:12, OR B1C55:14
  • Ignition ON.
  • Using a diagnostic scan tool, carry out the BCM self-test.
  • Using a diagnostic scan tool, carry out the SCCM self-test.

Is DTC B1C55:12 or B1C55:14 present?
Yes For DTC B1C55:12, GO to A3
For DTC B1C55:14, GO to A5
No GO to A9

A3 CHECK THE BCM-C HORN RELAY CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect BCMC C1035A .
  • Ignition ON.
  • Measure:
    Positive Lead Measurement / Action Negative Lead
      C1035A-20   Ground

Is any voltage present?
Yes GO to A4
No GO to A5

A4 ISOLATE THE BCM-C HORN RELAY CONTROL CIRCUIT SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect BCM C2280F .
  • Ignition ON.
  • Measure:
    Positive Lead Measurement / Action Negative Lead
      C1035A-20   Ground

Is any voltage present?
Yes REPAIR the circuit.
No GO to A17

A5 CHECK THE HORN RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Disconnect BCM C2280F .
  • Disconnect: negative battery cable.
  • Measure:
    Positive Lead Measurement / Action Negative Lead
      C2280F-20   Ground

Is the resistance greater than 10,000 ohms?
Yes GO to A7
No GO to A6

A6 ISOLATE THE HORN RELAY CONTROL CIRCUIT SHORT TO GROUND
  • Disconnect BCMC C1035A .
  • Measure:
    Positive Lead Measurement / Action Negative Lead
      C2280F-20   Ground

Is the resistance greater than 10,000 ohms?
Yes CHECK OASIS for any applicable TSB, GSB, SSM, or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new BCMC
REFER to: Body Control Module C (BCMC) (419-10 Multifunction Electronic Modules, Removal and Installation).
No REPAIR the circuit.

A7 CHECK THE HORN RELAY CONTROL CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Disconnect BCMC C1035A .
  • Measure:
    Positive Lead Measurement / Action Negative Lead
      C1035A-20   C2280F-20

Is the resistance less than 3 ohms?
Yes GO to A8
No REPAIR the circuit.

A8 CHECK THE BCM-C HORN RELAY CONTROL CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Connect BCMC C1035A.
  • Connect negative battery cable.
  • Ignition ON.
  • Measure:
    Positive Lead Measurement / Action Negative Lead
      C2280F-20   Ground

Is the voltage greater than 11 volts?
Yes GO to A17
No INSTALL a new BCMC.

A9 CHECK THE HORN POWER SUPPLY CIRCUIT
  • Ignition OFF.
  • Disconnect BCMC C1035B .
  • Disconnect Horn C131 .
  • Connect:
    Positive Lead Measurement / Action Negative Lead
      C131-2   C1035B-60
      C131-1   Ground

Are all resistance measurements less than 3 ohms?
Yes VERIFY Fuse 13 (7.5A) is OK. If not OK, use the wiring diagrams as a guide to identify the cause of the circuit short. If OK, INSTALL a new horn assembly.
REFER to: Horn (413-06 Horn, Removal and Installation).
No REPAIR the circuit in question.

A10 CHECK THE HORN SWITCH INPUT TO THE BCM (BODY CONTROL MODULE)
  • Ignition OFF.
  • Disconnect BCM C2280B.
  • While pressing the horn switch, measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2280B-18   Ground

Is the resistance less than 3 ohms?
Yes GO to A17
No GO to A11

A11 ISOLATE THE HORN SWITCH
  • Connect BCM C2280B.
  • Remove the driver airbag.
    REFER to: Driver Airbag (501-20B Supplemental Restraint System, Removal and Installation).
  • Momentarily connect a fused jumper wire:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C217-1   C217-2

Does the horn sound?
Yes REMOVE the fused jumper wire. INSTALL a new driver airbag (includes horn switch).
REFER to: Driver Airbag (501-20B Supplemental Restraint System, Removal and Installation).
No REMOVE the fused jumper wire. GO to A12

A12 CHECK THE HORN SWITCH SIGNAL CIRCUIT
  • Disconnect SCCM C218A.
  • Momentarily connect a fused jumper wire:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C218A-9   Ground

Does the horn sound?
Yes REMOVE the fused jumper wire. GO to A13
No REMOVE the fused jumper wire. REPAIR the open circuit.

A13 CHECK THE HORN SWITCH GROUND FROM THE HORN SWITCH
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C217-2   Ground

Is the resistance less than 3 ohms?
Yes GO to A15
No GO to A14

A14 CHECK THE HORN SWITCH GROUND WHILE BYPASSING THE SCCM
  • Disconnect SCCM C218A.
  • Disconnect SCCM C218B.
  • Connect a fused jumper wire:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C218A-8   C218B-5
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C217-2   Ground

Is the resistance less than 3 ohms?
Yes REMOVE the fused jumper wire. CHECK OASIS for any applicable TSB, GSB, SSM, or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new SCCM
REFER to: Steering Column Control Module (SCCM) (211-05 Steering Wheel and Column Electrical Components, Removal and Installation).
No REMOVE the fused jumper wire. GO to A15

A15 CHECK THE SCCM (STEERING COLUMN CONTROL MODULE) GROUND CIRCUITS FOR AN OPEN
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C226A-8   Ground

    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C218A-8   Ground

Is the resistance less than 3 ohms?
Yes GO to A16
No REPAIR the circuit.

A16 CHECK HORN OPERATION WITH STEERING WHEEL HARNESS ISOLATED
  • Disconnect SCCM C218B.
  • Momentarily connect a fused jumper wire:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
    Clockspring C218B, pin 5, component side   Ground

Does the horn sound?
Yes REMOVE the fused jumper wire. INSTALL a new steering wheel (includes steering wheel wiring harness).
REFER to: Steering Wheel (211-04 Steering Column, Removal and Installation).
No REMOVE the fused jumper wire. CHECK OASIS for any applicable TSB, GSB, SSM, or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new SCCM.
REFER to: Steering Column Control Module (SCCM) (211-05 Steering Wheel and Column Electrical Components, Removal and Installation).

A17 CHECK FOR CORRECT BCM (BODY CONTROL MODULE) OPERATION
  • Disconnect and inspect the BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Reconnect the BCM connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable TSB, GSB, SSM, or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern,
   Click here to access Guided Routine (BCM). Internet Explorer version 11 or greater is required to perform this Pinpoint Test.
No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.

PINPOINT TEST B : THE HORN IS ALWAYS ON- VEHICLES WITHOUT ADAPTIVE STEERING

Refer to Wiring Diagrams Cell 44 for schematic and connector information.

Normal Operation and Fault Conditions

REFER to: Horn - System Operation and Component Description (413-06 Horn, Description and Operation).

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
BCM B1323:11 Horn Switch: Circuit Short To Ground A Continuous Memory Diagnostic Trouble Code (CMDTC) that sets when the BCM detects a short to ground on the horn signal circuit.
BCM B1C55:14 Horn Relay: Circuit Short To Ground Or Open This DTC sets when the BCM detects a short to ground or an open on the horn relay control circuit.

Possible Sources

  • Wiring, terminals or connectors
  • Clockspring
  • BCMC
  • Horn switch
  • BCM
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
NOTICE: The following test uses a test light to simulate normal circuit loads. Use only a Rotunda Test Lamp (SGT27000) or 250-300mA incandescent bulb test lamp. To avoid connector terminal damage, use the Rotunda Flex Probe kit for the test lamp probe connection to the vehicle. Do not use the test lamp probe directly on any connector.
B1 MONITOR THE BCM (BODY CONTROL MODULE) HORN_SW PID (PARAMETER IDENTIFICATION)
  • Disconnect Horn C131.
  • Ignition ON.
  • Connect a diagnostic scan tool.
  • Using a diagnostic scan tool, view BCM Paramater Identifications (PIDs).

  • Access the  BCM  and monitor the  HORN_SW  PID


Does the PID status display OFF?
Yes GO to B2
No GO to B4

B2 CHECK THE HORN RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Disconnect BCM C2280F.
  • Connect:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C131-1   C131-2

Does the test light illuminate?
Yes GO to B3
No GO to B8

B3 ISOLATE THE HORN RELAY CONTROL CIRCUIT SHORT TO GROUND
  • Ignition OFF.
  • Disconnect BCMC C1035A.
  • Connect:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C1035A-20   Ground

Is the resistance greater than 10,000 ohms?
Yes INSTALL a new BCMC.
No REPAIR the short to ground on the horn relay control circuit.

B4 ISOLATE THE BCM (BODY CONTROL MODULE) HORN SWITCH INPUT CIRCUIT
  • Ignition OFF.
  • Disconnect BCM C2280B.
  • Connect:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C131-1   C131-2

Does the test light illuminate?
Yes GO to B8
No GO to B5

B5 CHECK THE HORN SWITCH INPUT CIRCUIT TO THE BCM (BODY CONTROL MODULE) FOR A SHORT TO GROUND
  • Disconnect Clockspring C218A.
  • Connect BCM C2280B.

Does the test light illuminate?
Yes REPAIR the circuit.
No GO to B6

B6 ISOLATE THE HORN SWITCH
  • Remove the driver airbag. Refer to the appropriate section in Group 501 for the procedure.
  • Disconnect Clockspring C218B.
  • Connect Clockspring C218A.

Does the test light illuminate?
Yes CHECK OASIS for any applicable TSB, GSB, SSM, or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new SCCM.
REFER to: Steering Column Control Module (SCCM) (211-05 Steering Wheel and Column Electrical Components, Removal and Installation).
No GO to B7

B7 ISOLATE THE STEERING WHEEL WIRING
  • Connect Clockspring C218B.

Does the test light illuminate?
Yes INSTALL a new steering wheel (includes steering wheel wiring harness).
REFER to: Steering Wheel (211-04 Steering Column, Removal and Installation).
No INSTALL a new driver airbag (includes horn switch).
REFER to: Driver Airbag (501-20B Supplemental Restraint System, Removal and Installation).

B8 CHECK FOR CORRECT BCM (BODY CONTROL MODULE) OPERATION
  • Disconnect and inspect the BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Reconnect the BCM connectors. Make sure they seat and latch correctly.
  • Connect Horn C131.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable TSB, GSB, SSM, or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, Perform
   Click here to access Guided Routine (BCM). Internet Explorer version 11 or greater is required to perform this Pinpoint Test.
No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.

PINPOINT TEST C : THE HORN IS INOPERATIVE- VEHICLES WITH ADAPTIVE STEERING

Refer to Wiring Diagrams Cell 44 for schematic and connector information.

Normal Operation and Fault Conditions

REFER to: Horn - System Operation and Component Description (413-06 Horn, Description and Operation).

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
BCM B1C55:12 Horn Relay: Circuit Short To Battery A Continuous Memory Diagnostic Trouble Code (CMDTC) that sets when the BCM detects a short to voltage on the horn relay control circuit. The BCM disables the horn when this DTC is set.
BCM B1C55:14 Horn Relay: Circuit Short To Ground Or Open This DTC sets when the BCM detects a short to ground or an open on the horn relay control circuit.

Possible Sources

  • Fuse
  • Wiring, terminals or connectors
  • Clockspring
  • Horn
  • Horn relay
  • Horn switch
  • BCM
  • BCMC

Visual Inspection and Pre-checks

  • Verify the BCM fuse 13 (7.5A) is OK.
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
C1 CHECK THE BCM (BODY CONTROL MODULE) OUTPUT BY ACTIVATING THE BCM (BODY CONTROL MODULE) HORN_RELAY PID (PARAMETER IDENTIFICATION)
  • Ignition ON.
  • Using a diagnostic scan tool, view BCM Parameter Identifications (PIDs).

  • Access the  BCM  and control the  HORN_RELAY  PID

    and command the horn ON and then OFF.

Does the horn sound when commanded ON?
Yes GO to C10
No GO to C2

C2 CHECK FOR BCM (BODY CONTROL MODULE) DTC (DIAGNOSTIC TROUBLE CODE) B1C55:12, OR B1C55:14
  • Ignition ON.
  • Using a diagnostic scan tool, carry out the BCM self-test.
  • Using a diagnostic scan tool, carry out the SCCM self-test.

Is DTC B1C55:12 or B1C55:14 present?
Yes For DTC B1C55:12, GO to C3
For DTC B1C55:14, GO to C5
No GO to C9

C3 CHECK THE BCM-C HORN RELAY CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect BCMC C1035A .
  • Ignition ON.
  • Measure:
    Positive Lead Measurement / Action Negative Lead
      C1035A-20   Ground

Is any voltage present?
Yes GO to C4
No GO to C5

C4 ISOLATE THE BCM-C HORN RELAY CONTROL CIRCUIT SHORT TO VOLTAGE
  • Ignition OFF.
  • Disconnect BCM C2280F .
  • Ignition ON.
  • Measure:
    Positive Lead Measurement / Action Negative Lead
      C1035A-20   Ground

Is any voltage present?
Yes REPAIR the circuit.
No GO to C17

C5 CHECK THE HORN RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Disconnect BCM C2280F .
  • Disconnect: negative battery cable.
  • Measure:
    Positive Lead Measurement / Action Negative Lead
      C2280F-20   Ground

Is the resistance greater than 10,000 ohms?
Yes GO to C7
No GO to C6

C6 ISOLATE THE HORN RELAY CONTROL CIRCUIT SHORT TO GROUND
  • Disconnect BCMC C1035A .
  • Measure:
    Positive Lead Measurement / Action Negative Lead
      C2280F-20   Ground

Is the resistance greater than 10,000 ohms?
Yes INSTALL a new BCMC.
No REPAIR the circuit.

C7 CHECK THE HORN RELAY CONTROL CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Disconnect BCMC C1035A .
  • Measure:
    Positive Lead Measurement / Action Negative Lead
      C1035A-20   C2280F-20

Is the resistance less than 3 ohms?
Yes GO to C8
No REPAIR the circuit.

C8 CHECK THE BCM-C HORN RELAY CONTROL CIRCUIT FOR AN OPEN
  • Ignition OFF.
  • Connect BCMC C1035A.
  • Connect negative battery cable.
  • Ignition ON.
  • Measure:
    Positive Lead Measurement / Action Negative Lead
      C2280F-20   Ground

Is the voltage greater than 11 volts?
Yes GO to C17
No INSTALL a new BCMC.

C9 CHECK THE HORN POWER SUPPLY CIRCUIT
  • Ignition OFF.
  • Disconnect BCMC C1035B .
  • Disconnect Horn C131 .
  • Connect:
    Positive Lead Measurement / Action Negative Lead
      C131-2   C1035B-60
      C131-1   Ground

Are all resistance measurements less than 3 ohms?
Yes VERIFY Fuse 13 (7.5A) is OK. If not OK, use the wiring diagrams as a guide to identify the cause of the circuit short. If OK, INSTALL a new horn assembly.
REFER to: Horn (413-06 Horn, Removal and Installation).
No REPAIR the circuit in question.

C10 CHECK THE HORN SWITCH INPUT TO THE BCM (BODY CONTROL MODULE)
  • Ignition OFF.
  • Disconnect BCM C2280B.
  • While pressing the horn switch, measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2280B-18   Ground

Is the resistance less than 3 ohms?
Yes GO to C17
No GO to C11

C11 ISOLATE THE HORN SWITCH
  • Connect BCM C2280B.
  • Remove the driver airbag.
    REFER to: Driver Airbag (501-20B Supplemental Restraint System, Removal and Installation).
  • Momentarily connect a fused jumper wire:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C217-1   C217-2

Does the horn sound?
Yes REMOVE the fused jumper wire. INSTALL a new driver airbag (includes horn switch).
REFER to: Driver Airbag (501-20B Supplemental Restraint System, Removal and Installation).
No REMOVE the fused jumper wire. GO to C12

C12 CHECK THE HORN SWITCH SIGNAL CIRCUIT
  • Disconnect CLOCKSPRING C218C.
  • Momentarily connect a fused jumper wire:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C218C-5   Ground

Does the horn sound?
Yes REMOVE the fused jumper wire. GO to C13
No REMOVE the fused jumper wire. REPAIR the open circuit.

C13 CHECK THE HORN SWITCH GROUND FROM THE HORN SWITCH
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C217-2   Ground

Is the resistance less than 3 ohms?
Yes GO to C15
No GO to C14

C14 CHECK THE HORN SWITCH GROUND WHILE BYPASSING THE CLOCKSPRING
  • Disconnect CLOCKSPRING C218G.
  • Disconnect CLOCKSPRING C218C.
  • Connect a fused jumper wire:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C218G-4   C218C-2
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C217-2   Ground

Is the resistance less than 3 ohms?
Yes REMOVE the fused jumper wire. CHECK OASIS for any applicable TSB, GSB, SSM, or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new CLOCKSPRING
REFER to: Clockspring (501-20B Supplemental Restraint System, Removal and Installation).
No REMOVE the fused jumper wire. GO to C15

C15 CHECK THE CLOCKSPRING GROUND CIRCUIT FOR AN OPEN
  • Measure:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C218C-2   Ground

    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C2414A-1   Ground

Is the resistance less than 3 ohms?
Yes GO to C16
No REPAIR the circuit.

C16 CHECK HORN OPERATION WITH STEERING WHEEL HARNESS ISOLATED
  • Disconnect CLOCKSPRING C218G.
  • Momentarily connect a fused jumper wire:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
    Clockspring C218G-1, component side   Ground

Does the horn sound?
Yes REMOVE the fused jumper wire. INSTALL a new steering wheel (includes steering wheel wiring harness).
REFER to: Steering Wheel - Vehicles With: Adaptive Steering (211-04 Steering Column, Removal and Installation).
No REMOVE the fused jumper wire. CHECK OASIS for any applicable TSB, GSB, SSM, or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new CLOCKSPRING.
REFER to: Clockspring (501-20B Supplemental Restraint System, Removal and Installation).

C17 CHECK FOR CORRECT BCM (BODY CONTROL MODULE) OPERATION
  • Disconnect and inspect the BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Reconnect the BCM connectors. Make sure they seat and latch correctly.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable TSB, GSB, SSM, or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern,
   Click here to access Guided Routine (BCM). Internet Explorer version 11 or greater is required to perform this Pinpoint Test.
No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.

PINPOINT TEST D : THE HORN IS ALWAYS ON- VEHICLES WITH ADAPTIVE STEERING

Refer to Wiring Diagrams Cell 44 for schematic and connector information.

Normal Operation and Fault Conditions

REFER to: Horn - System Operation and Component Description (413-06 Horn, Description and Operation).

DTC Fault Trigger Conditions

DTC Description Fault Trigger Condition
BCM B1323:11 Horn Switch: Circuit Short To Ground A Continuous Memory Diagnostic Trouble Code (CMDTC) that sets when the BCM detects a short to ground on the horn signal circuit.
BCM B1C55:14 Horn Relay: Circuit Short To Ground Or Open This DTC sets when the BCM detects a short to ground or an open on the horn relay control circuit.

Possible Sources

  • Wiring, terminals or connectors
  • Clockspring
  • BCMC
  • Horn switch
  • BCM
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
NOTICE: The following test uses a test light to simulate normal circuit loads. Use only a Rotunda Test Lamp (SGT27000) or 250-300mA incandescent bulb test lamp. To avoid connector terminal damage, use the Rotunda Flex Probe kit for the test lamp probe connection to the vehicle. Do not use the test lamp probe directly on any connector.
D1 MONITOR THE BCM (BODY CONTROL MODULE) HORN_SW PID (PARAMETER IDENTIFICATION)
  • Disconnect Horn C131.
  • Ignition ON.
  • Connect a diagnostic scan tool.
  • Using a diagnostic scan tool, view BCM Paramater Identifications (PIDs).

  • Access the  BCM  and monitor the  HORN_SW  PID

    .

Does the PID status display OFF?
Yes GO to D2
No GO to D4

D2 CHECK THE HORN RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND
  • Ignition OFF.
  • Disconnect BCM C2280F.
  • Connect:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C131-1   C131-2

Does the test light illuminate?
Yes GO to D3
No GO to D8

D3 ISOLATE THE HORN RELAY CONTROL CIRCUIT SHORT TO GROUND
  • Ignition OFF.
  • Disconnect BCMC C1035A.
  • Connect:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C1035A-20   Ground

Is the resistance greater than 10,000 ohms?
Yes INSTALL a new BCMC.
No REPAIR the short to ground on the horn relay control circuit.

D4 ISOLATE THE BCM (BODY CONTROL MODULE) HORN SWITCH INPUT CIRCUIT
  • Ignition OFF.
  • Disconnect BCM C2280B.
  • Connect:
    Click to display connectors
    Positive Lead Measurement / Action Negative Lead
      C131-1   C131-2

Does the test light illuminate?
Yes GO to D8
No GO to D5

D5 CHECK THE HORN SWITCH INPUT CIRCUIT TO THE BCM (BODY CONTROL MODULE) FOR A SHORT TO GROUND
  • Disconnect Clockspring C218G.
  • Connect BCM C2280B.

Does the test light illuminate?
Yes REPAIR the circuit.
No GO to D6

D6 ISOLATE THE HORN SWITCH
  • Remove the driver airbag.
    REFER to: Driver Airbag (501-20B Supplemental Restraint System, Removal and Installation).
  • Disconnect Clockspring C218G.

Does the test light illuminate?
Yes CHECK OASIS for any applicable TSB, GSB, SSM, or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new SCCM.
REFER to: Steering Column Control Module (SCCM) (211-05 Steering Wheel and Column Electrical Components, Removal and Installation).
No GO to D7

D7 ISOLATE THE STEERING WHEEL WIRING
  • Connect Clockspring C218G.

Does the test light illuminate?
Yes INSTALL a new steering wheel (includes steering wheel wiring harness).
REFER to: Steering Wheel - Vehicles With: Adaptive Steering (211-04 Steering Column, Removal and Installation).
No INSTALL a new driver airbag (includes horn switch).
REFER to: Driver Airbag (501-20B Supplemental Restraint System, Removal and Installation).

D8 CHECK FOR CORRECT BCM (BODY CONTROL MODULE) OPERATION
  • Disconnect and inspect the BCM connectors.
  • Repair:
    • corrosion (install new connector or terminals – clean module pins)
    • damaged or bent pins – install new terminals/pins
    • pushed-out pins – install new pins as necessary
  • Reconnect the BCM connectors. Make sure they seat and latch correctly.
  • Connect Horn C131.
  • Operate the system and determine if the concern is still present.

Is the concern still present?
Yes CHECK OASIS for any applicable TSB, GSB, SSM, or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, Perform
   Click here to access Guided Routine (BCM). Internet Explorer version 11 or greater is required to perform this Pinpoint Test.
No The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.


    Description and Operation - Horn - System Operation and Component Description

    System Operation System Diagram- Vehicles Without Adaptive Steering Item Description 1 Clockspring 2 Horn switch 3 SCCM 4 BCM 5 BCMC 6 Horn Horn Operation - Vehicles Without Adaptive Steering The horn switch consists of 2 sets of contacts separated by springs...

    Removal and Installation - Horn

    Removal NOTE: Removal steps in this procedure may contain installation details. Remove the front bumper cover. Refer to: Front Bumper Cover (501-19 Bumpers, Removal and Installation)...

    Other information:

    Lincoln Aviator 2020-2026 Service Manual: Overhaul - Transmission


    Special Tool(s) / General Equipment 100-001 (T50T-100-A) Slide Hammer 100-002 (TOOL-4201-C) Holding Fixture with Dial Indicator Gauge 205-1018Installation Tube 307-003 (T57L-500-B) Holding Fixture, Transmission 307-091Handle, Torque ConverterTKIT-2009TC-F 307-309Remover, Torque Converter SealTKIT-1994-FMH/FLMHTKIT-1994-LMH/MHTKIT-1994-FH 307-346 (T97T-7902-A) Retainer, Torque ConverterTKIT-1998-LM (NavigatoR)TKIT-1997-F/FLM/LT 307-549Installer, Shift Shaft Fluid SealTKIT-2005D1-F1 307-5842-6 Spring CompressorTKIT-2006UF-FLMTKIT-2006UF-ROW 307-589Overdrive clutch and balance piston service setTKIT-2006UF-FLMTKIT-2006UF-ROW 307-651Bracket, Pump Remover/Installer 307-651-02Lift fixture adapter for 307-651 307-661Gauge, End PlayTKIT-2009C-FTKIT-2009C-ROW 307-661-01Spacers/Plate, Clearance Gage 307-662Gauge, Clutch Pack EndplayTKIT-2009C-FTKIT-2009C-ROW 307-691Tester, Torque Convertor Leak 307-732Tool Kit, Torque Converter Flusher 307-732-02Adapter for 307-732 Converter flushing Mandrel 307-736Installer, Pump Drive Gear Bearing 307-737Press Tool, Oil Pump Drive Idler Gear 307-741Spring Compressor, F Clutch 307-743Remover, Pump Drive Gear 307-746Remover, Transmission Wiring Harness Connector 307-780Converter Seal installer 307-782Installer, Output Shaft Seal 307-783Installer, Roll Pin 307-784One way clutch alignment tool 307-785Clutch spring compressor 307-786F7 Seal Installer/Sizer Input Shaft 307-787F8 Seal Installer/Sizer Input Shaft 307-790Endplay Check Gauge 307-796F2 Seal Guide, Installer & Sizer 307-797Installer, Alignment Studs (3) & Alignment Pin (All 10R) 307-803F1 Seal Guide, Installer & Sizer 307-804F9 Seal Guide, Installer & Sizer Rubber Mallet Hydraulic Press Punch Wooden Block Magnet Materials Name Specification Motorcraft® MERCON® ULV Automatic Transmission FluidXT-12-QULV WSS-M2C949-A, MERCON® ULV  All vehicles Transmission overhaul includes the following: Complete disassembly of the transmission Cleaning and inspecting of all components Replacement of all seals, gaskets, and one time use components...

    Lincoln Aviator 2020-2026 Service Manual: Description and Operation - Transmission Description


    Transmission Assembly Item Part Number Description 1 79027902 Torque converter 2 W714629W714629 Transmission fluid pan stud bolts (6 required) 3 W500215W500215 Transmission fluid pan bolts (12 required) 4 7A1947A194 Transmission fluid pan 5 7A1917A191 Transmission fluid pan gasket 6 7E3897E389 Transmission fluid level indicator and plug assembly 7 W708500W708500 Transmission fluid auxiliary pump tube bolt (model dependent) 8 7A2097A209 Transmission fluid auxiliary pump tube (model dependent) 9 W718548W718548 Transmission fluid auxiliary pump bolts (3 required) (model dependent) 10 7P0867P086 Transmission fluid auxiliary pump (model dependent) 11 7J1357J135 Transmission fluid auxiliary pump tube seal (model dependent) 12 W700123W700123 Transmission fluid filter bolt (71 mm length) 13 W500214W500214 Transmission fluid filter bolt (20 mm length) 14 7G1867G186 Transmission fluid filter 15 W708500W708500 Main control-to-transmission case bolts (68 mm length) (8 required) 16 7A1007A100 Main control assembly 17 7N2657N265 Main control-to-transmission fluid pump seal 18 7M1837M183 Intermediate Speed A (ISSA) sensor 19 7M1017M101 Turbine Shaft Speed (TSS) sensor 20 7H1037H103 Intermediate Speed B (ISSB) sensor 21 7H1037H103 Output Shaft Speed (OSS) sensor 22 W500213W500213 Transmission internal wiring harness bolts (2 required) 23 7G2767G276 Transmission internal wiring harness 24 W500215W500215 Transmission fluid pump bolts (4 required) 25 7A1037A103 Transmission fluid pump 26 7Z3027Z302 Transmission fluid pump seal 27 66586658 Transmission fluid pump driven gear outer cover 28 W718158W718158 Transmission fluid pump retaining ring 29 7A0807A080 Transmission fluid pump driven gear 30 W504755W504755 Transmission fluid pump driven gear inner cover bolts (2 required) 31 66586658 Transmission fluid pump driven gear inner cover 32 7K4407K440 Output shaft flange nut (RWD only) 33 7A0217A021 Output shaft flange (RWD only) 34 7N1357N135 Anti-ting washer (RWD only) 35 7G1007G100 Manual control shaft-to-Transmission Range (TR) sensor roll pin 36 W712713W712713-S442-S442 Park override lever nut 37 7J1677J167 Park override lever 38 7C4937C493 Manual control shaft 39 7H5577H557 Transmission Range (TR) sensor 40 7L2527L252 Park return spring 41 7D4107D410 Park pawl actuator rod 42 W716607W716607 Transmission Range (TR) sensor detent spring bolt 43 7E3327E332 Transmission Range (TR) sensor detent spring 44 7N1347N134 Front support assembly bolts (12 required) 45 7G0337G033 Front support assembly 46 7M1577M157-C-C B clutch (overdrive) snap ring 47 7C5767C576 B clutch (overdrive) pressure plate 48 7B4427B442-A-A B clutch (overdrive) steel plates (quantity model dependent) 49 7B1647B164 B clutch (overdrive) friction plates (quantity model dependent) 50 7J4027J402 B clutch (overdrive) separating springs (quantity model dependent) 51 7B4427B442-B-B B clutch (overdrive) apply plate 52 7G2067G206 One-Way Clutch (OWC) 53 7G4187G418 B clutch (overdrive) piston 54 7N1697N169 A clutch (intermediate) piston return spring snap ring 55 7G2977G297 A clutch (intermediate) piston return spring 56 7J0157J015 A clutch (intermediate) piston 57 7F2257F225 A clutch (intermediate) piston inner seal 58 7F2247F224 A clutch (intermediate) piston outer seal 59 7B0317B031 Front support-to-case seal 60 7M1577M157-J-J Torque converter hub seal snap ring 61 7A2487A248 Torque converter hub seal 62 W500204W500204 Front support cover and seal assembly bolt 63 7M1577M157 Front support cover and seal assembly snap ring 64 75707570 Front support cover and seal assembly 65 7F0737F073 Transmission fluid pump drive gear 66 66516651 Transmission fluid pump idler gear 67 7Z4267Z426 Transmission fluid pump idler gear bearing 68 7G0907G090 Stator support seal 69 — Clutch and planetary assembly 70 7P0807P080 A clutch (intermediate) wave spring 71 7A4067A406 A clutch (intermediate) apply plate (select fit) 72 7F2197F219 A clutch (intermediate) friction plates (quantity model dependent) 73 7F2207F220 A clutch (intermediate) steel plates (quantity model dependent) 74 7G1597G159 A clutch (intermediate) separating springs (quantity model dependent) 75 7B4377B437 A clutch (intermediate) pressure plate 76 7J3007J300 Selective shim 77 7H0327H032 Thrust bearing (T3) 78 7M1527M152-A-A Thrust bearing (T9) 79 7A0497A049 Output shaft and planetary carrier No...

    Categories

    Adjusting the Steering Wheel - Vehicles With: Manual Adjustable Steering Column

    WARNING: Do not adjust the steering wheel when your vehicle is moving.

    Note: Make sure that you are sitting in the correct position.

    Unlock the steering column. Adjust the steering wheel to the desired position.

    Lincoln Aviator. Column

    Lock the steering column.

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