C05F1Rear Drive Shaft Speed Sensor Circuit High
- Generic OBD-II code · Chassis
- Can trigger limp mode
- How the car detects it
- Here the rear drive shaft speed signal reads above its valid range, as caused by a short to supply voltage, a damaged sensor IC or a fault at the module input. With a two-wire Hall sensor the module watches the current between a low and a high level (Allegro A19420: about 7 and 14 mA); a current clearly above the upper band cannot be a speed pulse. Without a plausible prop shaft speed, a disconnecting AWD system cannot judge when the rear driveline has caught up with the wheels, which the American Axle and BorgWarner patents require before engagement. Audi's quattro ultra uses such a sensor as G970. No manufacturer publishes C05F1; C05F0 is the low case, C05F4 the plausibility check.
- What you may notice
- AWD warning, all-wheel drive not connected
- Fault sets immediately at ignition on
- Likely causes
- LikelySensor signal line shorted to supply voltage
- PossibleDamaged sensor IC drawing excessive current
- RareFaulty sensor input in the AWD module
- Repair
- Medium · Often possible to do yourself.Typical cost: €50 – €400
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.