P2779 Possible Causes
- Faulty downshift switch
- Downshift switch harness is open or shorted
- Poor electrical connection in downshift switch circuit
How to Fix Code P2779
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
Illuminated engine light (or service engine soon warning light)
P2779 Meaning
The Engine Control Module (ECM) monitors the downshift switch circuit signal. The ECM sets the OBDII code when the downshift switch circuit signal is outside factory specifications.