Circuit Description
The body control module (BCM) uses the secondary serial data bus (circuit 1061) to poll the instrument cluster for information. DTC 13 will set if there is no instrument poll from the BCM for more than 10 seconds. In practice the trouble code is set somewhere between 10 and 20 seconds after the last instrument poll is received by the instrument cluster. The DTC is reset within 10 seconds of the arrival of an instrument poll from the BCM. The DTC is logged as a History DTC.
Diagnostic Aids
By manipulating the harnesses at the various connectors it is often possible to isolate the cause of the circuit interruption. This harness can then be removed and repaired. Inspect for any damage to the harness which could cause an intermittent open or short to ground or backed out terminals at the instrument cluster connectors, broken connector locks, improperly formed or damaged terminals. The multimeter allows continuity of the wiring harness circuit 1061 to be checked. If the fault cannot be found in the harness then the fault may lie in the sensing and diagnostic module (SDM) or the BCM. Refer to Diagnostic Starting Point - Computer/Integrating Systems for further diagnosis.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |
2 |
Does the Tech 2 display BCM information? | -- | Go to Step 3 | |
3 | Attempt to communicate with the BCM, engine control module (ECM), powertrain interface module (PIM) and instrument panel (I/P). Were you able to make contact with the specified modules? | -- | Go to Step 6 | Go to Step 4 |
4 | Using an ohmmeter, back probe the BCM connector 2 Primary universal asynchronous receiver transmitter (UART) Serial Data circuit and the Secondary UART Serial Data circuits. Is the value as specified? | Less than 10 ohms | Go to Step 5 | Go to Step 8 |
5 | Inspect the Secondary UART Serial Data circuit for an open, short to ground or short to voltage between the BCM and individual control modules. Refer to Circuit Testing and Wiring Repairs . Did you find and complete the repair? | -- | Go to Step 9 | Go to Step 7 |
6 | Check the Secondary UART Serial Data circuit between the BCM and the I/P for continuity. Is continuity present? | -- | Go to Step 9 | Go to Step 7 |
7 | Repair the open or high resistance in the Secondary UART Serial Data circuit between the powertrain control module (PCM) and the PIM. Refer to Wiring Repairs . Did you complete the repair? | -- | Go to Step 9 | -- |
8 | Replace the BCM. Refer to Body Control Module Replacement . Did you complete the replacement? | -- | Go to Step 9 | -- |
9 |
Does the DTC reset? | -- | Go to Step 2 | System OK |
