P279D Possible Causes
- Faulty all-wheel drive range chain
- Four-wheel drive range harness is open or shorted
- Poor electrical connection in the four-wheel drive range circuit
How to Fix Code P279D
Check the “Possible Causes” listed above. Visually inspect the wiring harness and related connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.
Possible Symptoms
Check Engine Light illuminated (or Service Engine Soon warning light)
P279D Meaning
The Transmission Control Module (TCM) monitors the signal from the four-wheel drive range signal circuit. The TCM sets the OBDII code when the four-wheel drive transmission range signal circuit signal is outside factory specifications.