For 1990-2009 cars

### DTC B1000 - ECU Malfunction

The body control module (BCM) performs an electrically erasable programmable read only memory (EEPROM) checksum as a part of its internal diagnostics as the BCM is operating. When the EEPROM checksum does not equal a predetermined value, the DTC sets. The checksum is the contents of each memory location in EEPROM added together.

### DTC Parameters

• | EEPROM checksum error exists.

• | The condition exists for 1 second.

• | Turns ON the service wrench telltale.

### Diagnostic Aids

If DTC B1000 is set, clear the DTCs using the scan tool. Cycle the ignition OFF. Wait 10 seconds. Cycle the ignition ON. If DTC B1000 remains a current code, replace the BCM.