For 1990-2009 cars

### Circuit Description

The body control module (BCM) performs a self-test when the ignition is turned on. If the BCM senses an internal error, DTC B1000 is set.

### Conditions for Running the DTC

The ignition switch is turned on.

### Conditions for Setting the DTC

Any of the following conditions may set this code:

• | An internal memory error.

• | An internal EEPROM checksum error.

• | An internal EEPROM write error.

• | An internal voltage regulation error.

### Action Taken When the DTC Sets

• | The SERVICE VEHICLE SOON indicator illuminates.

• | The check gauges chime sounds.

### Conditions for Clearing the DTC

• | A current DTC B1000 will clear when the code setting condition is no longer present.

• | A history DTC will clear if the condition is no longer present after 100 ignition cycles with no current codes active during the 100 ignition cycles.

### Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

1. If DTC B1000 is set as current, replace the BCM.

Step | Action | Yes | No
--- | --- | --- | ---
1 | Did you perform the Body Control Module Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Body Control System
2 | Replace the body control module. Refer to Body Control Module Replacement . Important: Perform the set up procedure for the body control module. Refer to Body Control Module (BCM) Programming/RPO Configuration . Did you complete the replacement? | System OK | --