What it means
The vehicle bus reports loss of communication with smart throttle/pedal position sensor D. The ECM loses one of the redundant pedal channels and reverts to a fail-safe pedal map.
At a glance
- Usually lights the warning light of the system that lost communication
- Affects emissions; the car can fail an emissions test
- The engine or gearbox may go into limp mode
How it works
Throttle/pedal position channel D is a networked input used by the engine controller as part of its redundant electronic throttle safety checks. This code sets when messages from channel D stop arriving, causing the controller to discard that input and use a fail-safe pedal strategy.
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 every module for related communication or throttle codes before clearing anything, since multiple faults can point to a shared network or power problem.
- Check live data for channel D status and the other pedal channels while slowly operating the pedal with the vehicle safely stationary.
- Inspect the channel D sensor connector and bus wiring for looseness, corrosion, water intrusion, or damage, paying particular attention to harness movement near the pedal assembly.
- Verify the sensor or module's power and ground against the manufacturer's procedure.
- Test the bus branch for opens and shorts, then isolate the channel D sensor or module if wiring and supplies are sound.
Common fixes
- Reconnect or clean the channel D connector.
- Repair damaged wiring or terminals in channel D's network circuit.
- Restore the sensor or module's power or ground.
- Replace the channel D sensor or module if testing confirms it has failed.
Can I keep driving?
Because loss of pedal channel D can trigger reduced or unpredictable throttle response, avoid driving in traffic or at speed; arrange repair promptly and stop if acceleration is unreliable. The engine may enter a fail-safe mode that limits power.
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.