Chassis, generic

C05F3 Rear Drive Shaft Speed Sensor Circuit

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

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.

Likely causes

Open signal or supply wire between sensor and module
Failed speed sensor IC
Connector not latched or pins pushed back
Faulty input stage in the AWD control module

Symptoms

  • 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

Repair estimate

DifficultyMediumDIY possible
Parts and labour€40–400
Time0.5–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

rear drive shaft speed sensorsensor wiring

Related codes

C05F0C05F1C05F2C05F4

References: allegromicro.com, patents.google.com, static.nhtsa.gov.