Possible Causes
| Possible Causes |
|---|
| (K902) O2 RETURN UPSTREAM CIRCUIT SHORTED TO GROUND |
| (K43) O2 2/1 SIGNAL CIRCUIT SHORTED TO GROUND |
| (K43) O2 2/1 SIGNAL CIRCUIT SHORTED TO THE (K902) O2 RETURN UPSTREAM CIRCUIT |
| (K43) O2 2/1 SIGNAL CIRCUIT SHORTED TO THE (Z42) HEATER GROUND CIRCUIT |
| O2 SENSOR |
| PCM |
Always perform the PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before proceeding.