P279F
Four Wheel Drive (4WD) Range Signal Circuit Low
Voltage on the 4WD range signal line is below the expected window. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: medium
Common causes
Ordered by how often each turns out to be the cause.
- Signal wire shorted to groundCommon
- Internal short in range sensorPossible
- Connector pins corroded - high contact resistanceLess likely
Parts involved
- Four Wd Range Sensor
- Wiring Harness
P279F is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.