Flash Code Method
- With ignition off, install jumper wire between pin "H" (White/Tan wire) and pin "A" (Black/White wire) of Assembly Line Data Link (ALDL) connector. The ALDL connector is located below left side of instrument panel, near steering column. See Fig 1.
- Turn ignition on. Diagnostic display mode will remain active as long as pin "H" is grounded, serial data link communications has not been initiated, and vehicle speed is less than 4 MPH.
- Approximately 3 seconds after ALDL pin "H" is grounded, EBCM will begin flashing SERVICE ABS light to indicate trouble codes in sequence. Sequence will start with Code 12 to signal the beginning of trouble code display.
- Each stored trouble code will be displayed 3 times. After all trouble codes are displayed, sequence will be repeated.
NOTE:
Codes 41, 45, 55, 61 and 63 can ONLY be read through ALDL using TECH 1 if trouble code is currently present (current code). The EBCM will not allow any trouble codes to be flashed if any of these codes is current. If trouble code existed previously (history code), but is not currently present, trouble code can be read using SERVICE ABS light.