Possible Causes
| Possible Causes |
|---|
| INTERMITTENT DTC |
| (K99) O2 1/1 HEATER CONTROL CIRCUIT SHORTED TO VOLTAGE |
| (K99) O2 1/1 HEATER CONTROL CIRCUIT SHORTED TO GROUND |
| (K99) O2 1/1 HEATER CONTROL CIRCUIT OPEN OR HIGH RESISTANCE |
| (A15) FUSED ASD RELAY OUTPUT CIRCUIT OPEN OR HIGH RESISTANCE |
| OXYGEN SENSOR |
| ENGINE CONTROL MODULE (ECM) |
Always perform the PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before proceeding.