P245CEGR Cooler Bypass Control Circuit Low (Bank 1)
- 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
- P245C reports that the control line of the bank 1 bypass actuator is pulled toward ground. GM documents this in its diesel tables: in 2014 the driver stage detects low voltage while it is switched off and treats it as a ground short, and in the 2017 tables the vacuum-switched bypass fails when the resistance to ground drops below 0.5 Ohm in 24 of 30 samples, rated Type B. With the line shorted the actuator may sit permanently in one position, so the cooler is either always bypassed or always used, which the efficiency check P2457 can then also notice. Typical findings are insulation rubbed through against the engine or exhaust, a pinched harness after repairs or a shorted solenoid winding. The open case is P245A, a short to supply P245D, and bank 2 has P2490.
- What you may notice
- Malfunction indicator lamp on
- Bypass stuck in one position, possibly with EGR cooler efficiency code
- Likely causes
- LikelyControl wire chafed through and touching ground
- PossibleShorted actuator or solenoid winding
- RareWater or corrosion bridging connector pins
- 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 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.