Possible Causes
| Possible Causes |
|---|
| (K43) O2 2/1 SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE |
| (K902) O2 RETURN (UPSTREAM) CIRCUIT FOR A SHORT TO VOLTAGE |
| (K43) O2 2/1 SIGNAL CIRCUIT FOR A SHORT TO THE (K199) O2 2/1 HEATER CONTROL CIRCUIT |
| (K43) O2 2/1 SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE |
| (K902) O2 RETURN (UPSTREAM) CIRCUIT OPEN OR HIGH RESISTANCE |
| 2/1 OXYGEN SENSOR |
| POWERTRAIN CONTROL MODULE (PCM) |
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE .