P0546: Exhaust Gas Temperature Sensor Circuit High (Bank 1 Sensor 1)
The P0546 code indicates that the Engine Control Module (ECM) has detected a high voltage signal from the exhaust gas temperature (EGT) sensor located before the catalytic converter on Bank 1. This sensor monitors exhaust temperature to protect the catalytic converter and turbocharger. A high voltage reading typically means the sensor circuit has an open, short to power, or the sensor itself is faulty. This can lead to incorrect fuel mixture adjustments and potential damage to emissions components.
01. Most Common Causes
- Faulty exhaust gas temperature sensor
- Open or shorted wiring in the sensor circuit
- Corroded or damaged connector
- ECM issue (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced fuel economy
- Possible limp mode or reduced engine power
- Overheating of catalytic converter (if ignored)
03. Step-by-Step Diagnosis
Step 1: Scan for codes and verify P0546 is present. Check freeze frame data for conditions.
Step 2: Visually inspect the EGT sensor connector and wiring for damage, corrosion, or loose connections.
Step 3: Using a multimeter, measure the sensor's resistance (typically 100-200k ohms at cold) and compare to specs. Also check for short to power or ground.
Step 4: If sensor and wiring appear okay, replace the EGT sensor (Bank 1 Sensor 1). Clear codes and test drive.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances with P0546. The ECM may limit engine power to protect the catalytic converter, and continued driving could cause converter damage.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for a DIY replacement of the sensor. Professional repair including diagnosis and labor may cost $150-$300.