P24C5 code meaning
EGR Cooler Bypass Position Sensor Exceeded Learning Limit Bank 2
Powertrain system Generic code P24xx codes Check engine light
What P24C5 means
P24C5 belongs to engines with a second EGR cooler and bypass flap on bank 2. It reports that the end positions learned by that flap's position sensor fall outside the accepted window, so the controller can no longer trust where the flap really stands. No manufacturer documents P24C5 publicly; GM's diesel engines in the available tables use one bypass valve and only show the bank 1 code P24C4. There the learning runs after key-off with a warm engine and checks the raw voltage at both end stops against fixed bands, which gives a good picture of what the bank 2 test checks. CARB requires position feedback of emission-related actuators to be monitored for rationality. Electrical faults of the same sensor are P2497 to P249B; the bank 1 learning fault is P24C4.
P24C5 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyHard
- Typical labor1 to 4 hours
- Clears after repairAfter a drive cycle
Symptoms of P24C5
- Malfunction indicator lamp on
- Higher NOx emissions due to poorly controlled EGR cooling
Common causes of P24C5
- Most likelyWorn bank 2 bypass valve or sensor track
- PossibleDeposits changing the end positions of the bank 2 flap
- Less likelySignal shift caused by wiring or connector resistance
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
EGR cooler bypass position sensor b2
What each part of P24C5 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). |
| C5 | The exact fault in that area. |
What to do next
- Note P24C5 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 P24C5
What does P24C5 mean?
P24C5 means "EGR Cooler Bypass Position Sensor Exceeded Learning Limit Bank 2". P24C5 belongs to engines with a second EGR cooler and bypass flap on bank 2. It is a generic code, so it means the same on every make.
Is it safe to drive with P24C5?
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 P24C5 fail an emissions test?
Yes, it can. P24C5 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 P24C5 to fix?
Difficulty: hard. A typical repair takes 1 to 4 hours of work. This is a job for a workshop.
Will P24C5 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.