Body Control System Diagnosis

B1000 - ECU Malfunction


CIRCUIT DESCRIPTION
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, this DTC fails. The checksum is the contents of each memory location in EEPROM added together.

DTC PARAMETERS
EEPROM checksum error exists

DIAGNOSTIC AIDS
^ If DTC B1000 is current, clear DTCs using the Scan tool. Cycle the ignition OFF. Wait 10 seconds. Cycle ignition ON. If DTC B1000 remains a current code, replace the BCM and program using the procedure in the Saturn Service Stall System (SSS) users guide.
^ If DTC B1000 is history only, do not replace the BCM.

TEST

Diagnostic Chart: