C05F0 code meaning
Rear Drive Shaft Speed Sensor Circuit Low
What C05F0 means
The signal of the rear drive shaft speed sensor stays below its valid range, typically due to an open circuit, a short to ground or a missing sensor supply. The AWD module needs this speed to match a disconnected rear driveline to the wheels before a clutch closes; American Axle's patent feeds a pinion shaft speed sensor into exactly that synchronisation check. Audi lists the driveshaft speed sensor G970 among the parts tested in quattro ultra fault finding for C05ED00. Many such sensors are two-wire Hall ICs that toggle between two supply currents; Allegro's A19420 uses about 7 and 14 mA, so a current below the lower band, or none at all, cannot be a valid pulse. No manufacturer publishes C05F0 itself; C05F1 is the high counterpart.
C05F0 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 2 hours
- Clears after repairWhen cleared with a scanner
Symptoms of C05F0
- AWD warning, all-wheel drive not connected
- Vehicle drives in front-wheel drive only
Common causes of C05F0
- Most likelyOpen sensor wire or loose connector
- PossibleSignal or supply line shorted to ground
- PossibleFailed Hall sensor IC
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Rear drive shaft speed sensor
What each part of C05F0 means
| C | Chassis system: brakes, ABS, steering and suspension. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| F0 | The exact fault in that area. |
What to do next
- Note C05F0 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about C05F0
What does C05F0 mean?
C05F0 means "Rear Drive Shaft Speed Sensor Circuit Low". The signal of the rear drive shaft speed sensor stays below its valid range, typically due to an open circuit, a short to ground or a missing sensor supply. It is a generic code, so it means the same on every make.
Is it safe to drive with C05F0?
Drive gently and only to a workshop. With C05F0 the car can go into limp mode (reduced power) to protect itself.
Will C05F0 fail an emissions test?
C05F0 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is C05F0 to fix?
Difficulty: medium. A typical repair takes 0.5 to 2 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will C05F0 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.