This code indicates that the engine computer has detected a voltage signal from the exhaust gas temperature sensor on Bank 2, Sensor 2 that is higher than the expected range. Bank 2 refers to the side of the engine opposite cylinder 1, and Sensor 2 is downstream of the catalytic converter (or diesel particulate filter). A high-voltage condition typically points to an open circuit, a failed sensor, or a wiring problem rather than an actual over-temperature condition.
The sensor itself has an internal open or has degraded, causing the signal voltage to stay at the high reference level. This is the most common cause of a high-circuit code.
A broken, chafed, or disconnected wire in the sensor signal or ground circuit will cause the computer to see a high voltage. Exhaust heat and vibration commonly damage nearby wiring.
Corrosion, bent pins, or a poorly seated connector at the sensor can create an open-circuit condition, producing a high-voltage reading at the PCM.
A significant exhaust leak upstream of or near the sensor can alter readings and, in rare cases, contribute to sensor damage or abnormal signal behavior.
An internal failure in the PCM's temperature-sensor input circuit is extremely rare and should only be considered after all wiring, connector, and sensor testing is exhausted.
On gasoline vehicles the code often causes no drivability issues, but it should be addressed to avoid masking other problems and to pass emissions. On diesel vehicles, it can interfere with DPF regeneration and may trigger reduced power mode.
No. A 'circuit high' code refers to the electrical signal voltage being too high, which usually indicates an open circuit or failed sensor. It does not necessarily mean the exhaust gas temperature is dangerously elevated.
No. Replacing the PCM is almost never the correct fix for this code. The overwhelming majority of cases are caused by a failed sensor, damaged wiring, or a corroded connector. The PCM should be tested and ruled out only as a last step.
Bank 2 is the side of the engine opposite the cylinder designated as cylinder 1. Sensor 2 is the downstream exhaust gas temperature sensor, located after the catalytic converter or diesel particulate filter on that bank.