Cause
Melted wiring against the exhaust
Insulation melted where a loom has touched a manifold, downpipe or turbocharger — often after a heat shield has rusted away or been left off. Missing heat shields are the root cause and get replaced far less often than the wiring does, so a repaired harness in the same position fails again.
Typically a moderate job.
Codes this can cause (12)
Codes where this is a likely explanation first, rather than merely a possible one.
- P2234 O2 Sensor Signal Circuit Shorted to Heater Circuit Bank 2 Sensor 1 Likely for this code High
- P2238 O2 Sensor Positive Current Control Circuit Low Bank 1 Sensor 1 Likely for this code High
- P2241 O2 Sensor Positive Current Control Circuit Low Bank 2 Sensor 1 Likely for this code High
- P2252 O2 Sensor Negative Current Control Circuit Low Bank 1 Sensor 1 Likely for this code High
- P2255 O2 Sensor Negative Current Control Circuit Low Bank 2 Sensor 1 Likely for this code High
- P2231 O2 Sensor Signal Circuit Shorted to Heater Circuit Bank 1 Sensor 1 High
- P2232 O2 Sensor Signal Circuit Shorted to Heater Circuit Bank 1 Sensor 2 Moderate
- P2233 O2 Sensor Signal Circuit Shorted to Heater Circuit Bank 1 Sensor 3 Moderate
- P2235 O2 Sensor Signal Circuit Shorted to Heater Circuit Bank 2 Sensor 2 Moderate
- P2236 O2 Sensor Signal Circuit Shorted to Heater Circuit Bank 2 Sensor 3 Moderate
- P2245 O2 Sensor Reference Voltage Circuit Low Bank 1 Sensor 1 High
- P2249 O2 Sensor Reference Voltage Circuit Low Bank 2 Sensor 1 High
Information, not instruction
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