Circuit Description
The remote control door lock receiver (RCDLR) communicates with the body control module (BCM) through the keyless entry serial data circuit. When any button on the keyless entry transmitter is pressed, the transmitter sends a signal to the RCDLR. The RCDLR sends a lock, unlock, rear release, or panic alarm request to the BCM, depending on which button is pressed on the transmitter. The BCM receives the message and performs the appropriate function. The BCM also uses the keyless entry serial data circuit in order to communicate with the RCDLR when programming transmitters.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B1003 BCM Does Not Receive an Acknowledgment Message From the RCDLR
Conditions for Running the DTC
| • | The system voltage is at least 9 volts and no more than 16 volts. |
| • | This condition can only occur during transmitter programming. |
Conditions for Setting the DTC
The BCM does not receive an acknowledgment message from the RCDLR within 300 milliseconds of a second Programming Mode/Diagnostic Mode request.
Action Taken When the DTC Sets
The keyless entry system will not operate.
Conditions for Clearing the DTC
| • | A current DTC will clear when the fault is no longer present and the ignition switch is cycled. |
| • | A history DTC will clear after 100 consecutive ignition cycles without a fault present. |
| • | A scan tool may be used to clear history and current DTCs. |
Diagnostic Aids
| • | Always begin diagnosis with the first DTC listed on the scan tool. |
| • | Perform a visual inspection for loose or poor connections at all related components. |
| • | If the DTC B1003 is a history DTC, the fault may be intermittent. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Keyless Entry Schematics | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 |
Does the test lamp illuminate? | Go to Step 3 | Go to Step 4 |
Test the keyless entry serial data circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 8 | Go to Step 5 | |
4 | Inspect for poor connections at the harness connector of the RCDLR. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 8 | Go to Step 6 |
5 | Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 8 | Go to Step 7 |
6 |
Important: All transmitters which are to be recognized by the RCDLR must be programmed in a single programming sequence. If the system is placed in program mode it will erase all previously programmed transmitters upon the receipt of the programming signal from the first transmitter. Replace the RCDLR. Refer to Remote Control Door Lock Receiver Replacement . Did you complete the replacement? | Go to Step 8 | -- |
7 |
Important: Perform the BCM programming procedure when replacing the BCM. Refer to Body Control Module (BCM) Programming/RPO Configuration in Computer/Integrating Systems for replacement, setup, and programming. Replace the BCM. Refer to Body Control Module Replacement in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | Go to Step 8 | -- |
8 |
Does the DTC reset? | Go to Step 2 | System OK |
