C05F3Rear Drive Shaft Speed Sensor Circuit
- Generic OBD-II code · Chassis
- Can trigger limp mode
- How the car detects it
- Catch-all electrical fault for the rear drive shaft speed sensor circuit, stored when the controller detects a problem but does not narrow it to low, high or intermittent. Typical are an open supply or signal wire, a failed sensor IC or a fault in the module input. Two-wire Hall sensors such as the Allegro A19420 report speed as alternating current levels and can also signal an internal error; a current outside both bands cannot be read as speed. The value matters for disconnecting AWD systems: BorgWarner reads sleeve speed and position with one Hall sensor and engages a dog clutch only within about 100 to 200 rpm, and Audi names sensor G970 in its quattro ultra diagnosis. No maker documents C05F3 itself; C05F0 and C05F1 are the more specific variants.
- What you may notice
- AWD or 4WD service message, all-wheel drive switched off
- Vehicle drives on the primary axle only
- No drive shaft speed shown in live data
- Likely causes
- LikelyOpen signal or supply wire between sensor and module
- PossibleFailed speed sensor IC
- PossibleConnector not latched or pins pushed back
- RareFaulty input stage in the AWD control module
- Repair
- Medium · Often possible to do yourself.Typical cost: €40 – €400
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.