Diagnostic Routine A
Diagnostic Routine A
Diagnostic Overview
All Door Locks Are Inoperative
Refer to Wiring Diagram Set 117 for schematic and connector information Electrical Diagrams.
Normal Operations and Fault Conditions
The RFA (Remote Function Actuator) module supplies voltage and ground to all of the door lock actuators by controlling the lock all and unlock all relays. The non-serviceable lock relays inside the RFA (Remote Function Actuator) module receive voltage from the BCM (Body Control Module). The lock relays receive ground through a dedicated ground circuit to the RFA (Remote Function Actuator) module. Upon a lock request, the RFA (Remote Function Actuator) module supplies voltage on the all door lock circuit and ground on the driver and passenger door unlock circuits. Upon an unlock request, the voltage and ground are reversed on the previously listed circuits. When the door lock and unlock relays are not energized, they are connected to ground.
The RFA (Remote Function Actuator) module receives inputs from the keyless entry keypad, and the IA (Intelligent Access) key data from the TPM (Tire Pressure Monitor) module. The BCM (Body Control Module) receives input from the door lock control switches and both modules share the information obtained from the inputs over the MS-CAN (Medium Speed Controller Area Network).
Visual Inspection and Diagnostic Pre-checks
- BCM (Body Control Module) fuse 27 (20A)
Pinpoint Test
1. VERIFY THE DOOR LOCK OPERATION FROM THE DOOR LOCK CONTROL SWITCH AND IA (Intelligent Access) KEY
1. Press the lock and unlock button on a door lock control switch and IA (Intelligent Access) key while observing the door lock operation.
Are the door locks inoperative from both the switch and IA (Intelligent Access) key?
2. VERIFY ALL DOOR LOCKS ARE INOPERATIVE
1. Press the lock and unlock buttons from a door lock control switch while observing the door locks.
Are all the door locks inoperative from both switch positions (lock and unlock)?
3. CHECK THE RFA (Remote Function Actuator) MODULE DOOR LOCK RELAY SUPPLY CIRCUIT FOR VOLTAGE
1. Ignition OFF.
2. Disconnect: RFA (Remote Function Actuator) Module C2153C.
3. Measure:
Is the voltage greater than 11 volts?
4. CHECK THE RFA (Remote Function Actuator) MODULE DOOR LOCK RELAY VOLTAGE SUPPLY CIRCUIT FOR AN OPEN
1. Disconnect: BCM (Body Control Module) C2280A.
2. Measure:
Is the resistance less than 3 ohms?
5. CHECK THE RFA (Remote Function Actuator) MODULE GROUND CIRCUIT FOR AN OPEN
1. Disconnect: RFA (Remote Function Actuator) Module C2153D.
2. Measure:
Is the resistance less than 3 ohms?
6. CHECK THE ALL LOCK CIRCUIT FOR AN OPEN
1. Disconnect: RH (Right Hand) Front Door Latch.
2. Measure:
Is the resistance less than 3 ohms?
7. CHECK THE ALL LOCK CIRCUIT FOR A SHORT TO GROUND
1. NOTE: If the BCM (Body Control Module) fuse 27 (20A) fails immediately upon installation, repair circuit SBP27 (BU) for a short to ground.
Install a new BCM (Body Control Module) fuse 27 (20A).
2. Operate the door lock actuators by pressing lock on the door lock control switch.
Is the BCM (Body Control Module) fuse 27 (20A) OK?
8. CHECK FOR CORRECT BCM (Body Control Module) OPERATION
1. Ignition OFF.
2. Disconnect and inspect all BCM (Body Control Module) connectors.
3. 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
4. Reconnect the BCM (Body Control Module) connectors. Make sure they seat and latch correctly.
5. Operate the system and determine if the concern is still present.
Is the concern still present?
9. CHECK FOR CORRECT RFA (Remote Function Actuator) MODULE OPERATION
1. Ignition OFF.
2. Disconnect and inspect all RFA (Remote Function Actuator) module connectors.
3. 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
4. Reconnect the RFA (Remote Function Actuator) module connectors. Make sure they seat and latch correctly.
5. Operate the system and determine if the concern is still present.
Is the concern still present?
