C058A code meaning
Brake Booster Motor A Position Sensor Circuit Range/Performance
Chassis system Generic code C05xx codes Check engine light
What C058A means
C058A covers a position signal of booster motor A that is electrically valid but not believable. GM uses it widely: its 2016 and 2019 hybrid tables flag a rotor angle changing faster than 73° per ms, the 2019 IBC unit an invalid Hall pattern (all three high or all low) and a frozen signal, the XT4 module a vector length outside 0.6889–1.2996, and the 2023/2025 tables angle jumps beyond 711.2 rad/s – each Type A with MIL. NXP likewise treats Hall patterns 000 and 111 as an interface fault. GM's PIC6614 lists C058A for the Cadillac Lyriq with a brake assist failure message; Stellantis names it alongside C0582 for the Jeep Wagoneer and asks for BSCM and eBooster to be replaced together.
C058A at a glance
- Check engine lightYes, usually on
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor1 to 4 hours
- Clears after repairWhen cleared with a scanner
Symptoms of C058A
- Brake assist failure message, abnormal pedal feel
- Check engine and brake warning lamps (GM)
- Fault may be hard to read out with a normal scan tool
Common causes of C058A
- Most likelyPosition sensor delivering implausible angles (Hall element or sine/cosine sensor degraded)
- PossibleIntermittent contact or interference on the sensor lines causing angle jumps
- PossibleBooster unit internal fault or position data no longer matching the stored calibration
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Booster motor a pos sensor
What each part of C058A means
| C | Chassis system: brakes, ABS, steering and suspension. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 8A | The exact fault in that area. |
What to do next
- Note C058A 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 C058A
What does C058A mean?
C058A means "Brake Booster Motor A Position Sensor Circuit Range/Performance". C058A covers a position signal of booster motor A that is electrically valid but not believable. It is a generic code, so it means the same on every make.
Is it safe to drive with C058A?
Drive gently and only to a workshop. With C058A the car can go into limp mode (reduced power) to protect itself.
Will C058A fail an emissions test?
C058A 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 C058A to fix?
Difficulty: workshop only. A typical repair takes 1 to 4 hours of work. This is a job for a workshop.
Will C058A clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.