What it means
The multiple EGT sensors on bank 2 disagree by more than the diagnostic tolerance under stable conditions - one of them has drifted relative to the others.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Exhaust gas temperature sensors on bank 2 measure temperatures at different exhaust locations for the control module's exhaust and aftertreatment checks. P24C3 sets when multiple bank 2 sensor readings disagree beyond the permitted correlation under stable conditions.
Common causes
Most likely first.
- Exhaust gas temperature sensor drift or failure
- Damaged sensor wiring
- Loose or corroded connector
- Exhaust leak affecting a sensor reading
Symptoms
- Check-engine light on
- Aftertreatment or exhaust warning
- Reduced engine power
- Emissions inspection failure
How to diagnose it
- Save freeze-frame data and compare live readings from all bank 2 exhaust temperature sensors under stable operating conditions.
- Inspect each bank 2 sensor connector and exhaust-area harness for heat damage, chafing, corrosion, or loose pins.
- Check the exhaust near the bank 2 sensors for leaks that could alter one sensor's reading.
- Compare sensor responses during warm-up or a supported scan-tool test to identify which bank 2 reading is biased or unresponsive.
- Test the suspect sensor and its wiring against the manufacturer's specification before replacing components.
Common fixes
- Repair heat-damaged or chafed wiring to a bank 2 temperature sensor.
- Clean or repair loose or corroded sensor connector terminals.
- Repair an exhaust leak near the affected bank 2 sensor.
- Replace the bank 2 temperature sensor that fails testing.
Can I keep driving?
Driving may be possible, but reduced power or an aftertreatment warning can occur and emissions performance may suffer. Avoid heavy loads if power is reduced, and stop if an urgent temperature or exhaust warning appears.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.