Exhaust Gas Temperature Sensor Circuit High (Bank 2 Sensor 1)

What You Might Notice

• Check Engine Light illuminated
• No immediately noticeable drivability issues
• Possible rough idle or hesitation under load
• Potential fuel trim adjustments by the ECM
• Vehicle may enter reduced power mode on some models

Most Common Causes

1. 1

   Loose or corroded connectors

   Corroded or disconnected wiring terminals at the EGT sensor connector are the most common cause, creating poor electrical contact and high circuit resistance.

2. 2

   Broken or damaged wiring

   Cracked insulation or broken wires in the EGT sensor circuit can cause shorts to ground or open circuits, sending incorrect voltage signals to the ECM.

3. 3

   Failed EGT sensor

   The exhaust gas temperature sensor itself may have internally failed, causing it to produce an abnormally high voltage output regardless of actual exhaust temperature.

4. 4

   Engine control module failure

   Although rare, the ECM may have a defective input circuit that misinterprets normal sensor signals as excessively high voltage.

How to Diagnose It

1. 1

   Check Loose or corroded connectors — Corroded or disconnected wiring terminals at the EGT sensor connector are the most common cause, creating poor electrical contact and high circuit resistance.

2. 2

   Check Broken or damaged wiring — Cracked insulation or broken wires in the EGT sensor circuit can cause shorts to ground or open circuits, sending incorrect voltage signals to the ECM.

3. 3

   Check Failed EGT sensor — The exhaust gas temperature sensor itself may have internally failed, causing it to produce an abnormally high voltage output regardless of actual exhaust temperature.

4. 4

   Check Engine control module failure — Although rare, the ECM may have a defective input circuit that misinterprets normal sensor signals as excessively high voltage.

How to Fix It

1. 1

   Inspect and clean connectors

   Locate the EGT sensor connector on Bank 2 Sensor 1, disconnect it, and clean all terminals with electrical contact cleaner. Check for corrosion, bent pins, or loose terminals and reconnect firmly.

2. 2

   Check wiring harness condition

   Visually inspect the entire EGT sensor wiring harness from the sensor to the ECM for cuts, cracks, or exposed insulation. Repair or replace damaged sections as needed.

   EGT Sensor Wiring Harness↗
3. 3

   Replace EGT sensor

   If connectors and wiring test acceptable, unbolt the failed sensor from the exhaust manifold or pipe and install a new EGT sensor, ensuring proper torque specifications.

   Exhaust Gas Temperature Sensor Bank 2 Sensor 1↗
4. 4

   Test engine control module

   If all other components test good, have the ECM professionally scanned and tested for input circuit faults. ECM replacement is rarely necessary but may be required if internal circuitry has failed.