P2499EGR Cooler Bypass Position Sensor Circuit Low (Bank 2)
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- P2499 stands for a bank 2 bypass position voltage that has fallen to the bottom of its range. No manufacturer documents the bank 2 code publicly. For orientation, GM's 2017 Duramax tables fail the bank 1 sensor (P2494) once its output drops under one percent of the supply and need 200 bad results out of 250 before the Type B fault is stored. A comparable bank 2 check would react to the same electrical causes: the signal wire grounded somewhere along the harness, the sensor supply interrupted or shorted, or a sensor that no longer drives its output. If other 5 V sensors report low values simultaneously, the shared reference circuit is the better starting point. High voltage on bank 2 is P249A, the bank 1 low code P2494.
- What you may notice
- Check engine light on
- Bank 2 bypass position reads near zero
- Likely causes
- LikelyBank 2 signal wire touching ground
- Possible5 V sensor supply interrupted or pulled down
- RareSensor output stage failed
- 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: €30 – €800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.