Test Description

WARNING: This page is about a different car, the 2003 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.

The numbers below refer to the step numbers on the diagnostic table.

3. Use the scan tool in order to determine if the delivered torque signal has a valid duty cycle.
9. This vehicle is equipped with a PCM which uses an Electrically Erasable Programmable Read Only Memory (EEPROM). When replacing the PCM, the replacement PCM must be programmed.

Fig 1: DTC C1276, P1644, or P1689 Diagnostic System Check (Step 1-7)

Courtesy of GENERAL MOTORS CORP.

Fig 2: DTC C1276, P1644, or P1689 Diagnostic System Check (Step 8-11)

Courtesy of GENERAL MOTORS CORP.