EGR Cooler Bypass Control Circuit Low Bank 1
What it means
P245C means the ECM detected a low-voltage (short-to-ground or open) condition in the control circuit for the bank 1 EGR cooler bypass valve. This valve routes exhaust gas either through or around the EGR cooler to manage EGR temperature and emissions. With the circuit faulted the valve can't be commanded properly, so temperature control and emissions suffer, though the engine usually still runs.
Can I keep driving? Usually drivable, but the EGR cooler bypass valve may not be controlled correctly, raising emissions and, over time, affecting performance — have it checked soon.
Common symptoms
What you'll notice
- Check-engine light on
- Reduced fuel economy or minor loss of performance
- Higher emissions or a failed emissions test
- On diesels, incomplete or delayed particulate-filter (DPF) regeneration
Common causes
Most likely first
- Short-to-ground or open in the EGR cooler bypass valve control wiringLikely
- Corroded or loose connector at the bypass valveCommon
- Failed EGR cooler bypass valve or its control solenoidCommon
- Poor ground for the control circuitLess often
- Rarely, an ECM driver faultLess often
How to diagnose & fix
Work through it in order
- Scan for codes and record freeze-frame data to see the operating conditions.
- Inspect the bypass valve connector and wiring for shorts to ground, corrosion, or heat damage.
- Measure the solenoid resistance and compare against specification.
- Test the control wire for a short-to-ground or open back to the ECM.
- Replace the bypass valve if it fails testing, then clear and re-test.
FAQ
Quick answers
Is it safe to drive with P245C?+
Can I just clear P245C?+
Related codes
Often seen with P245C
Read & clear P245C yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.