P0545Exhaust Gas Temperature Sensor Circuit Low Bank 1 Sensor 1
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- The exhaust gas temperature sensor is a thermistor in a voltage divider with the module's pull-up resistor; the first one (sensor 1) sits before the turbocharger, the oxidation catalyst or after it depending on the maker. Diesels use it for particulate filter regeneration and component protection; CARB names it explicitly as a monitored input. P0545 means the signal is below range: GM L5P below 142 Ω in 10 of 20 samples, GM LML below 0.65 V, Ford 6.7 L below 0.10 V for about 2 s, Saab 9-5 2.0 TiD below 0.1 V for 1 s. Usually a signal shorted to ground. GM USA uses two trips, GM Europe in the Saab one. The module uses a substitute value and blocks filter regeneration.
- What you may notice
- Check engine light on
- Particulate filter regeneration missing, filter warning
- Possible power reduction
- Likely causes
- LikelySignal line shorted to ground (chafed on the exhaust or bracket)
- PossibleSensor shorted internally
- PossibleConnector damp or corroded
- RareEngine module
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €60 – €300
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.