P245C code meaning
EGR Cooler Bypass Control Circuit Low (Bank 1)
Powertrain system Generic code P24xx codes Check engine light
What P245C means
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.
P245C at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 3 hours
- Clears after repairAfter a drive cycle
Symptoms of P245C
- Malfunction indicator lamp on
- Bypass stuck in one position, possibly with EGR cooler efficiency code
Common causes of P245C
- Most likelyControl wire chafed through and touching ground
- PossibleShorted actuator or solenoid winding
- Less likelyWater or corrosion bridging connector pins
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
EGR cooler bypass valve b1
What each part of P245C means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 4 | Area: auxiliary emission controls (catalytic converter, EGR, EVAP). |
| 5C | The exact fault in that area. |
What to do next
- Note P245C and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P245C
What does P245C mean?
P245C means "EGR Cooler Bypass Control Circuit Low (Bank 1)". P245C reports that the control line of the bank 1 bypass actuator is pulled toward ground. It is a generic code, so it means the same on every make.
Is it safe to drive with P245C?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P245C fail an emissions test?
Yes, it can. P245C is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P245C to fix?
Difficulty: medium. A typical repair takes 0.5 to 3 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P245C clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.