Possible Causes
| Possible Causes |
|---|
| (K243) O22/2 SIGNAL CIRCUIT SHORTED TO BATTERY VOLTAGE |
| (K904) O2 DOWNSTREAM RETURN CIRCUIT SHORTED TO BATTERY VOLTAGE |
| (K243) O2 2/2 SIGNAL CIRCUIT OPEN |
| (K904) O2 DOWNSTREAM RETURN CIRCUIT OPEN |
| O2 SENSOR |
| PCM |
Always perform the PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before proceeding.