System Operation
System Diagrams
NOTE: The Phone As A Key feature can also be used to lock/unlock the vehicle. Refer to section 419-01C for information regarding this feature.
NOTE: Not all vehicles come equipped with all the items listed in the system diagrams. The door latch control modules are identified as follows:
Door Unlatch Request and Door Cinch
Item | Description |
---|---|
1 | DCMH |
2 | Exterior Latch Release Switch |
3 | GWM |
4 | PCM |
5 | Interior Latch Release Switch |
6 | Door Cinch Motor |
7 | DCME |
8 | Exterior Latch Release Switch |
9 | Interior Latch Release Switch |
10 | Door Cinch Motor |
11 | DCMF |
12 | Exterior Latch Release Switch |
13 | Interior Latch Release Switch |
14 | Door Cinch Motor |
15 | DCMG |
16 | Exterior Latch Release Switch |
17 | Interior Latch Release Switch |
18 | Door Cinch Motor |
19 | IPC |
20 | BCM |
Door Lock/Unlock
Item | Description |
---|---|
1 | Turn Signals |
2 | Horn |
3 | Fuel Filler Door Release Solenoid |
4 | Exterior Sounder |
5 | PCM |
6 | Hybrid Vehicles |
7 | Headlamp Switch |
8 | Fuel Door Release Switch |
9 | Fuel Filler Door Ajar Switch |
10 | Fuel Filler Door Lock |
11 | Non-Hybrid Vehicles |
12 | BCM |
13 | GWM |
14 | DCME |
15 | DCMF |
16 | DCMG |
17 | DCMH |
18 | Keyless Entry Door Antennas |
19 | Passive Key |
20 | RTM |
21 | GWM |
22 | Keyless Entry Keypads |
23 | Door Lock Control Switch |
24 | Lock Indicator |
25 | Exterior Door Lock Sensor |
26 | DCME |
27 | Door Lock Control Switch |
28 | Lock Indicator |
29 | Exterior Door Lock Sensor |
30 | DCMF |
31 | Door Lock Control Switch |
32 | Lock Indicator |
33 | DCMG |
34 | Door Lock Control Switch |
35 | Lock Indicator |
36 | DCMH |
37 | Master Window Control Switch |
38 | DDM |
39 | PDM |
40 | GWM |
41 | RGTM |
42 | Door Lock Switch |
RKE Transmitter
Item | Description |
---|---|
1 | BCM |
2 | Passive Key |
3 | RTM |
4 | GWM |
5 | GWM |
6 | Turn Signals |
7 | Horn |
8 | Fuel Filler Door Lock |
9 | Exterior Sounder |
10 | RGTM |
11 | DCMH |
12 | DCME |
13 | DCMF |
14 | DCMG |
Approach Detection and Passive Entry
Item | Description |
---|---|
1 | Exterior Latch Release Switch |
2 | BCM |
3 | Passive Key |
4 | Keyless Entry Rear Antenna |
5 | RTM |
6 | GWM |
7 | Keyless Entry Door Antennas |
8 | Approach Detection Antenna |
9 | Exterior Latch Release Switch |
10 | Exterior Door Lock Sensor |
11 | Exterior Door Lock Sensor |
12 | DCMH |
13 | DCME |
14 | DCMF |
15 | DCMG |
16 | GWM |
17 | RGTM |
18 | Exterior Latch Release Switch |
19 | Exterior Latch Release Switch |
20 | DCME |
21 | DCMH |
22 | DCMG |
23 | DCMF |
24 | Exterior Liftgate Switch |
25 | RGTM |
26 | Power Liftgate Hands Free Actuation Module |
27 | Fuel Filler Door Lock |
Network Message Chart
BCM Network Input Messages
Broadcast Message | Originating Module | Message Purpose |
---|---|---|
Child lock request | DDM | Provides the BCM with the child lock request when the child lock button is pressed on the master window control switch. |
Door lock switch status | DDM/ PDM | Provides the BCM with lock/unlock requests based on the input from the door lock control switch. |
RKE data | RTM | Provides the BCM with the RKE commands and passive key information. |
Vehicle speed | PCM | Provides the BCM with the vehicle speed. The BCM uses this message to determine when to activate some features, such as the autolock feature. |
IPC Network Input Messages
Broadcast Message | Originating Module | Message Purpose |
---|---|---|
Door latch fault | DCME/ DCMF/ DCMG/ DCMH | Provides the IPC with the request to display a fault message in the message center. |
DCME/ DCMF/ DCMG/ DCMH Network Input Messages
Broadcast Message | Originating Module | Message Purpose |
---|---|---|
Vehicle lock status | BCM | Provides the door latch control modules with the vehicle lock/unlock status. The door latch control modules use this message to determine when to allow the electronic latch to release without the request of passive key information. |
Vehicle speed | PCM | Provides the door latch control modules with the vehicle speed. The door latch control modules use this message to determine when to allow the electronic latch to release when the vehicle is in motion. |
Window lockout status | BCM | Provides the door latch control modules with the vehicle lock/unlock status. The door latch control modules use this message to determine when to allow the electronic latch to release without the request of passive key information. |
RGTM Network Input Messages
Broadcast Message | Originating Module | Message Purpose |
---|---|---|
Vehicle lock status | BCM | Provides the RGTM with the lock/unlock status. The RGTM uses this message to determine when to allow the power liftgate to open when a power liftgate switch is pressed. |
Electronic Door Unlatch and Door Cinch
The doors are electronically unlatched and if equipped with cinch motors, electronically pull the door closed when the secondary latch (first click) is detected. Each door latch communicates on the MS-CAN and is identified by the scan tool as follows:
Door Unlatch
The doors can be unlatched when the door latch control modules are in the unlock mode. The BCM sends vehicle lock status messages over the network as well as providing wired voltage signals (one for lock and one for unlock) to each door latch control module.
Each door latch control module sends multiple voltage signals to the inside and outside door handle release switches. When a door latch release switch is activated, the voltage signals change, indicating a request to unlatch the door. When the door latch control module detects the request to unlatch the door, it activates an internal solenoid to release the door latch.
When either door latch release switch is disconnected, a DTC sets in the respective door latch control module. When a door latch control module detects a fault from any of the inputs or outputs to the door latch, it sends a message to the IPC to display a door latch fault message.
Each door latch control module has an internal power backup, allowing the door latch release to function for approximately 20 activations or approximately 72 hours after a power loss (such as a disconnected or depleted battery).
Door Cinch (if equipped)
The door latch control module provides voltage to the cinch motor when it detects the door is latched in the secondary latch position (first click), such as when the door is not pulled with enough force to fully latch the door in the primary position (second click). When the door latch control module detects the door is fully latched, it reverses the polarity to the cinch motor to reset its position.
Electronic Door Locks
Each door latch is a door latch control module that communicates on the network. The door latches do not use actuators to lock/unlock the doors. They rely on inputs from the BCM to determine if the door should be in lock or unlock mode. Locking and unlocking the doors is handled electronically and no moving parts are involved with regards to locking or unlocking the doors.
The BCM is the master module that controls the door locks. The BCM uses a series of Field Effect Transistor (FET) controlled circuits in place of integrated relays. They are used for:
A lock and unlock signal is provided to each door latch control module. The BCM is able to provide voltage and ground to the door lock circuits to actuate a solenoid when present. When a lock or unlock request is carried out by the BCM, it provides voltage and ground to the lock and unlock circuits to each door latch control module as appropriate. When a door latch control module detects the voltage and ground combination, the door latch control module interprets that as a signal to electronically lock or unlock the door.
The door latch control modules send voltage signals to their respective door lock control switch. When a door lock control switch is pressed, the voltage signal is routed to ground, indicating a request to lock/unlock the doors.
For the front doors, the DDM and PDM send voltage signals to their respective front door latch control module. When a front door latch control module detects a lock or unlock request from a front door lock control switch, it grounds the respective voltage signal from the DDM or PDM. The DDM or PDM then sends a message over the CAN to the BCM to lock or unlock the doors.
The BCM sends voltage signals to the rear door latch control modules. When a rear door latch control module detects a lock or unlock request, it grounds the respective voltage signal from the BCM to lock or unlock the doors.
When the BCM receives a valid lock or unlock request, it energizes the appropriate relay(s) to provide a voltage signal to the door latch control modules to either lock or unlock the door
Each door latch control module also monitors the lock and unlock request signals from the corresponding door lock control switch.
Based on input from the door lock control switches, the keyless entry keypad, the passive entry system and the RKE transmitter, the BCM unlocks the driver door, unlocks all the doors or locks all the doors.
The door latch control modules also provide an unlock override feature in the event of a severe crash event. Depending on the severity of the crash event, the RCM provides a network message and wired voltage signal to the door latch control modules. Approximately 10 seconds after the door latch control modules detect this input from the RCM, they enter a crash unlock mode to allow the doors to unlatch from the inside or outside door latch release switches. The crash unlock mode is exited by cycling the ignition on and off twice.
Rear Door Child Safety Locks (if equipped)
The power child lock feature is used to electronically activate the rear door child safety lock feature. This feature operates in conjunction with the rear power windows lock-out feature. When the lock-out switch is placed in the LOCK position with the ignition on, the rear door child safety lock feature activates.
The master window control switch monitors the rear window lock-out switch. When the rear window lock-out switch is pressed, the master window control switch sends a message over a LIN circuit to the DDM. The DDM then communicates the child safety lock request to the BCM over the CAN. The BCM then sends a window lockout message to the rear door latch control modules.
When the rear door child safety lock feature is active, the rear doors do not open from the interior door latch release switch.
LED Door Lock Indicators
Each door lock control switch has a door lock indicator to indicate the lock or unlock status of that individual door. The door lock indicators are controlled by the door latch control modules. When the door is in lock mode, the door latch control module provides voltage to the door lock indicator.
The door latch control modules only provide voltage to the Light Emitting Diodes (LEDs) during lock mode when the ignition is on or when the battery saver feature has not activated when the ignition is off.
Switch Inhibit Feature
The switch inhibit feature prevents unauthorized access to the vehicle from the door lock control switches. The BCM disables the function of both door lock control switches switch 20 seconds after the vehicle is electronically locked. If any of these switches are activated while they are inhibited, a chime sounds and a message is displayed in the message center to indicate the switches are inhibited. The BCM enables the function of these switches when the vehicle is electronically unlocked.
The BCM also sends a switch inhibit message to the door latch control modules and the RGTM over the network.
This feature can be configured on/off through the message center.
Power Liftgate
For power liftgate information,
Refer to: Body Closures - System Operation and Component Description (501-03 Body Closures, Description and Operation).
Fuel Filler Door Release (hybrid vehicles)
The PCM sends a voltage signal to the fuel filler door release switch located on the headlamp switch. When the button is pressed, the signal is routed to a return circuit, indicating a request to release the fuel filler door latch.
When the PCM detects the fuel filler door release switch is pressed, it checks the fuel tank for excessive fuel vapor pressure. If excess fuel tank vapor pressure is detected, the PCM activates a pump to remove the excess pressure.
When the PCM detects the excess pressure is removed, it provides voltage and ground to the fuel filler door release solenoid, releasing the fuel filler door latch. The process to release the fuel filler door can take as long as 15 seconds.
In the event the electronic fuel filler door release system fails, the fuel filler door latch can be released manually using the manual fuel filler door release cable.
Keyless Entry Keypads
The keyless entry keypads are integrated into the front door window mouldings. The BCM receives data from the keyless entry keypads over a LIN-based circuit.. When a keypad button is touched, the button press data is sent to the BCM. When a valid code is received, the BCM sends a lock or unlock command to the door latch control module(s).
RKE
The RKE feature is controlled by the BCM. When a button is pressed, the Transmitter Identification Code (TIC) and RKE command is received by the RTM. The RTM interprets the information and sends a message to the BCM over a LIN circuit and, when the network is awake, over the CAN. If the BCM detects a valid programmed key, it carries out the command by sending a lock/unlock command to the door latch control modules or sending a message to the RGTM to power open/close the liftgate, or activating the horn or turn signals as required.
The RKE transmitters have a normal operating range of 30 m (98 ft) in an open air, no obstruction environment.
The RKE transmitters and the BCM also utilize a rolling code to prevent the code from being captured by a code grabber. The system advances the counter in the RKE transmitter and the BCM every time a RKE transmitter button is pressed.
Passive Entry
NOTE: The passive entry and the RKE system share operation of several components including the passive keys, the BCM and the RTM. If there is a concern with any of these components, the passive entry and the RKE system can both be affected.
When the BCM detects the battery state of charge to be below a pre-determined level, the passive entry feature only operates from the driver door.
Doors
With a programmed passive key within 1 m (3.28 ft) outside a door, touch the lock sensor at the bottom of the front door window moulding or activate the exterior door latch release switch. The doors lock or unlock and unlatch depending upon which input the BCM receives.
The driver front door passive entry feature either unlocks the driver door (if 2-stage unlock is enabled) or all four doors (if 2-stage unlock is disabled). The passive entry feature always locks all four doors when the lock sensor is touched for a half second.
The remaining doors passive entry feature always locks or unlocks all four doors.
Liftgate
With a programmed passive key within 1 m (3.28 ft) outside the liftgate, press the liftgate button on the rear of the vehicle to power open the liftgate.
Door Passive Entry
Door Unlock and Unlatch
When the doors latch control modules are in lock mode and the request to unlatch the door is detected from the outside door latch release switch, the door lock control module sends a passive entry unlock request through a circuit monitored by the BCM.
When the BCM detects a passive entry unlock request, it activates the keyless entry door antennas (located aft of the rear wheels between the body and rear bumper cover). The keyless entry door antenna sends out a low frequency signal to the passive key. The low frequency signal activates the passive key and the passive key sends a high frequency signal to the RTM. The RTM interprets the high frequency signal from the passive key and sends the key information to the BCM. If the BCM detects a valid programmed passive key, the BCM either commands the driver door to unlock or all the doors to unlock. The respective door latch control module then releases the door latch.
The passive entry unlock feature does not activate if the doors are in unlock mode.
Door Lock
The passive entry door lock touch sensors (located at the bottom of each front door window moulding) are provided voltage by the BCM at all times. The sensor and the integrated lock LED is monitored and controlled by the respective front door latch control module. When the front door latch control module detects the lock sensor is touched, the door lock control module sends a passive entry lock request through a circuit monitored by the BCM.
When the BCM detects a passive entry lock request, it activates the keyless entry door antennas. The keyless entry door antenna sends out a low frequency signal to the passive key. The low frequency signal activates the passive key and the passive key sends a high frequency signal to the RTM. The RTM interprets the high frequency signal from the passive key and sends the key information to the BCM. If the BCM detects a valid programmed passive key, the BCM commands all the doors to lock.
The passive entry lock feature does not activate if the doors are in lock mode.
The passive entry door lock touch sensors are integrated into the front door upper window mouldings.
Liftgate Passive Entry
When the BCM is in lock mode and the liftgate button is pressed or the liftgate hands free request is detected, it activates the rear keyless entry antenna inside the cargo area. The rear keyless antenna sends out a low frequency signal to the passive key. The low frequency signal activates the passive key and the passive key sends a high frequency signal to the RTM. The RTM interprets the high frequency signal from the passive key and sends the information to the BCM. If the BCM detects a valid programmed passive key, the BCM sends a request to the RGTM to power open the liftgate.
Approach Detection
When the approach detection feature is active, the BCM uses the door keyless antennas, the keyless entry antenna and the approach detection antenna to detect a valid programmed passive key when approaching within 2.7 m (8.5 ft) of the vehicle. When the BCM detects a valid programmed passive key, the illuminated entry feature activates.
Component Description
Door Lock Control Switches
The DDM and PDM provide voltage signals through the corresponding front door latch control module to the door lock control switch for the lock and unlock requests. When a lock or unlock button is pressed, the corresponding input circuit is routed to ground, indicating a request to lock or unlock the doors.
The BCM provides voltage signals through the rear door latch control modules to the corresponding rear door lock control switch for the lock and unlock requests. When a switch is pressed to lock or unlock, the corresponding input circuit is routed to ground, indicating a request to lock or unlock the doors.
Door Lock Indicators
Each door lock indicator is integrated into a door lock control switch. They are controlled by the respective door latch control module.
Exterior Door Latch Release Switch
The exterior door latch release switch is integrated into the exterior door handle assembly (exterior door window belt moulding). It is constantly monitored by the door latch control module. If the door latch control module detects a fault, a DTC sets and a message displays in the message center when the ignition is turned on to indicate a fault.
Interior Door Latch Release Switch
The interior door latch release switch is mounted to the door trim panel, just below the grab handle. It is constantly monitored by the door latch control module. If the door latch control module detects a fault, it sends a message to the IPC over the network to inform the driver of a door latch fault.
Fuel Filler Door Release Switch (hybrid vehicles)
The fuel filler door release switch is integrated into the headlamp switch. It is supplied a voltage signal from the PCM for the fuel filler door release request. When the switch is pressed to release the fuel filler door, the input is routed to the return circuit, indicating a request to release the fuel filler door latch.
Fuel Filler Door Release Solenoid (hybrid vehicles)
The fuel filler door ajar switch is integrated into the fuel filler door release solenoid. The PCM monitors the fuel filler door ajar switch and if it detects a fault with the fuel filler release system, sends messages to the IPC to indicate a fault is detected.
Fuel Filler Door Lock (non-hybrid vehicles)
The fuel filler door lock activates in conjunction with the driver front door. When the driver front door is electronically locked or unlocked, the fuel filler door also locks or unlocks.
Keyless Entry Keypads
The keyless entry keypads are touch-sensitive capacitive sensors integrated into the front door window moulding. When a finger touches the keypad, it changes the capacitance of the sensor in the area of the finger touch. The keypad determines which area is touched and communicates the number/button touched to the BCM over a LIN. The keypad only works when touched with a finger. The keyless entry keypad may not work when gloves are worn. The gloves act as an insulator and do not allow the finger to change the sensor capacitance.
The passive entry door lock touch sensors are integrated into the front door upper window mouldings and not replaced separately.
Passive Key
The passive key incorporates both the PATS and RKE transmitter functions in a single device.
During key programming procedures, the PATS and RKE transmitter identification of a passive key are both programmed. A maximum of 4 passive keys can be programmed.
In the event the passive key battery fails:
Keyless Entry Door Antennas
The keyless entry door antennas are activated by the BCM. When activated, they transmit a low frequency signal to activate a passive key.
Keyless Entry Rear Antenna
The keyless entry rear antenna is activated by the BCM. When activated, it transmits a low frequency signal to activate a passive key.
Door Latch Control Module
The door latch control modules are sealed units and contain the door latch release actuator, the door ajar switch, a door latch cinch motor (if equipped), sensors to monitor the latch position and a module that communicates on the network to control the door latch functions. The door latches can be lubricated, if needed.
The door latch control modules require PMI when replaced.
Cinch Motor (if equipped)
The cinch motor is controlled by the door latch control module. It is mounted to the door latch control module and cannot be serviced separately.
DDM or PDM
The DDM and the PDM monitor the door lock control switches and control the operation of the power windows and the power mirrors. They communicate with each other and the BCM over the CAN.
The DDM and PDM require PMI when replaced.
RTM
The RTM communicates all RKE and passive key information to the BCM over a LIN-based circuit whether or not the CAN is active. The RTM is a receiving antenna that receives the high frequency signals from passive keys.
The RTM requires PMI when replaced.
BCM
The BCM is the master module in control of the power door lock system. It is responsible for locking/unlocking the doors. The BCM receives inputs for the door lock control switches, passive keys and RKE commands over the CAN.
The BCM requires PMI when replaced. Additionally, carry out the parameter reset procedure and program at least 2 keys.
The intelligent access key must be within 3 ft (1 m) of the door or luggage compartment you intend to lock or unlock.
At a Door
Electronic door handles are on each door. Gently depress the switch inside the exterior door handle to unlock and open the door. An unlock symbol illuminates on the door window trim indicating your vehicle is unlocked.