Possible Causes
| Possible Causes |
|---|
| O2 SENSOR HEATER CONTROL CIRCUIT SHORTED TO GROUND |
| O2 SENSOR HEATER CONTROL CIRCUIT OPEN |
| EXCESSIVE RESISTANCE IN THE ASD RELAY OUTPUT CIRCUIT TO THE O2 SENSOR |
| O2 SENSOR |
| POWERTRAIN CONTROL MODULE (PCM) |
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .