Cause
Damaged wiring harness near exhaust heat
Insulation baked hard and cracked where a loom runs close to a manifold, downpipe or turbocharger. The fault often appears only when hot and clears as the vehicle cools, which is exactly the pattern that makes it hard to catch on a cold workshop test.
Typically a moderate job.
Codes this can cause (34)
Codes where this is a likely explanation first, rather than merely a possible one.
- P0403 Exhaust Gas Recirculation A Control Circuit/Open Likely for this code Moderate
- P0414 Secondary Air Injection System Switching Valve A Circuit Shorted Likely for this code Low
- P0417 Secondary Air Injection System Switching Valve B Circuit Shorted Likely for this code Low
- P0425 Catalyst Temperature Sensor Circuit Bank 1 Sensor 1 Likely for this code Low
- P0435 Catalyst Temperature Sensor Circuit Bank 2 Sensor 1 Likely for this code Low
- P0470 Exhaust Pressure Sensor A Circuit Likely for this code Moderate
- P0474 Exhaust Pressure Sensor A Circuit Intermittent/Erratic Likely for this code Moderate
- P0479 Exhaust Pressure Control Valve A Intermittent Likely for this code Low
- P0486 Exhaust Gas Recirculation Sensor B Circuit Likely for this code Low
- P0489 Exhaust Gas Recirculation A Control Circuit Low Likely for this code Moderate
- P0490 Exhaust Gas Recirculation A Control Circuit High Likely for this code Moderate
- P0520 Engine Oil Pressure Sensor/Switch A Circuit Likely for this code High
- P0544 Exhaust Gas Temperature Sensor Circuit — Bank 1 Sensor 1 Likely for this code Moderate
- P0545 Exhaust Gas Temperature Sensor Circuit Low — Bank 1 Sensor 1 Likely for this code Moderate
- P0546 Exhaust Gas Temperature Sensor Circuit High — Bank 1 Sensor 1 Likely for this code Moderate
- P0547 Exhaust Gas Temperature Sensor Circuit — Bank 2 Sensor 1 Likely for this code Moderate
- P0548 Exhaust Gas Temperature Sensor Circuit Low — Bank 2 Sensor 1 Likely for this code Moderate
- P0549 Exhaust Gas Temperature Sensor Circuit High — Bank 2 Sensor 1 Likely for this code Moderate
- P0641 Sensor Reference Voltage A Circuit Open Likely for this code High
- P0642 Sensor Reference Voltage A Circuit Low Likely for this code High
- P0651 Sensor Reference Voltage B Circuit Open Likely for this code High
- P0652 Sensor Reference Voltage B Circuit Low Likely for this code High
- P0697 Sensor Reference Voltage C Circuit Open Likely for this code High
- P0698 Sensor Reference Voltage C Circuit Low Likely for this code High
- P0405 Exhaust Gas Recirculation Sensor A Circuit Low Low
Information, not instruction
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