P0549 Exhaust Gas Temperature Sensor Circuit High Bank 2 Sensor 1

P0549 indicates a high signal from Exhaust Gas Temperature Sensor Bank 2 Sensor 1. The upstream Bank 2 EGT feedback is above expected limits.

Code details

Generic OBD-II · P0

System: Speed / Idle
Code type: Generic (SAE / ISO controlled)
Standard: SAE J2012 / ISO 15031-6

Diagnostic boundary

A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.

Do not dismiss P0549 as a sensor-only issue until true high exhaust temperature has been ruled out.

Symptoms of P0549

Unstable, high, or low idle, or stalling.
Erratic speedometer, cruise-control, or shift behaviour.
Check-engine light with a hesitation or surge.

Common causes of P0549

A dirty throttle body, idle-control valve, or throttle-position sensor.
A failing vehicle-speed or wheel-speed sensor, or its wiring.
Vacuum leaks or a related sensor forcing the idle/speed strategy.

Useful checks before replacing parts

Review Bank 2 EGT voltage, bias or reference voltage, ground path, engine load, fueling, boost, aftertreatment status, and freeze-frame data.
Inspect for open grounds, short-to-voltage faults, connector heat damage, wiring routed too close to exhaust, and true overheating conditions.
Compare Bank 2 cold and hot readings with Bank 1 to decide whether the signal is stuck high or reflecting real temperature.

Related OBD-II codes

These nearby speed / idle entries can help compare wording and pin down the fault area.