What it means
The vehicle bus reports loss of communication with smart EGR temperature sensor D. EGR cooling diagnostic switches to model-based estimation.
At a glance
- Usually lights the warning light of the system that lost communication
- Affects emissions; the car can fail an emissions test
How it works
EGR temperature sensor D is a smart sensor that reports temperature over the vehicle communication bus. This code sets when messages from sensor D are lost, so the EGR cooling diagnostic must rely on a modeled temperature estimate instead of its live input.
Common causes
Most likely first.
- Bus wiring open or shorted
- Module without power or ground
- Module failed
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
How to diagnose it
- Save freeze-frame data and scan all modules for communication codes to identify when EGR temperature sensor D went offline and whether other network devices are affected.
- Locate sensor D using vehicle service information, then inspect its connector and harness for loose pins, corrosion, heat damage, or chafing.
- Check the sensor module's power and ground following the manufacturer's procedure to rule out a supply fault.
- Inspect the bus wiring and splices to sensor D for opens or shorts, then test the communication circuit as specified by the manufacturer.
- If wiring and supply circuits are good, use a capable scan tool to confirm sensor D does not respond before replacing the sensor/module.
Common fixes
- Reconnect or repair sensor D's connector and damaged terminals.
- Repair an open, short, or damaged splice in sensor D's bus wiring.
- Restore the sensor module's power or ground.
- Replace EGR temperature sensor D if it remains offline after its circuits check out.
Can I keep driving?
A short, gentle drive is generally reasonable if the vehicle runs normally and no exhaust or overheating warnings appear, but avoid heavy loads if EGR warnings are active. Repair the fault soon because the EGR cooling diagnostic lacks sensor D's live reading and emissions performance may be affected.
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.