P1779 Transmission Control Indicator Lamp Circuit Malfunction
What does P1779 mean on a Ford?
P1779 — Transmission Control Indicator Lamp Circuit Malfunction. This Ford-enhanced code applies to F-150, Explorer, Ranger with O/D off lamps.
Common causes of P1779
- Burned-out indicator bulb
- Open lamp circuit
- Failed lamp driver
- Corroded cluster connector
- LED swap without proper load
How to fix P1779
- Confirm the lamp illuminates at bulb check
- Test the bulb and circuit
- Inspect cluster connections
- Restore factory loading if LEDs were fitted
- Repair the lamp circuit