C003F code meaning
Wheel Speed Sensors Rotation Direction Correlation
What C003F means
A correlation code set when the directional information from the wheel speed sensors does not agree across wheels or with other motion inputs. Directional (bidirectional) wheel speed sensors tell the ABS/ESC module whether a wheel turns forward or backward, which the module uses for hill-hold, rollback detection and stability functions. The code stores when one wheel reports a rotation direction that is implausible against the others, the selected gear or the yaw and acceleration sensors. It points to a faulty directional sensor, its wiring or the tone ring. Affected functions are disabled and the ABS warning lamp is set while base braking remains. Direction-capable sensor ICs such as Allegro's A19302 send speed plus direction over PW or AK protocol. No manufacturer documents this code publicly.
C003F at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 2.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of C003F
- ABS warning lamp on
- Hill-hold or stability functions disabled
- Incorrect rollback or direction detection
Common causes of C003F
- Most likelyFaulty directional wheel speed sensor
- PossibleDamaged tone ring giving false direction
- Less likelySensor wiring fault or miswire
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Wheel speed sensors
What each part of C003F means
| C | Chassis system: brakes, ABS, steering and suspension. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 3F | The exact fault in that area. |
What to do next
- Note C003F 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 C003F
What does C003F mean?
C003F means "Wheel Speed Sensors Rotation Direction Correlation". A correlation code set when the directional information from the wheel speed sensors does not agree across wheels or with other motion inputs. It is a generic code, so it means the same on every make.
Is it safe to drive with C003F?
Drive gently and only to a workshop. With C003F the car can go into limp mode (reduced power) to protect itself.
Will C003F fail an emissions test?
C003F 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 C003F to fix?
Difficulty: medium. A typical repair takes 0.5 to 2.5 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will C003F clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.