C0043 code meaning
Brake Pedal Position Sensor Circuit B
What C0043 means
Covers circuit B of the brake pedal position sensor, the redundant second channel that the module cross-checks against channel A (C0042). Dual-channel pedal position sensors provide two independent voltage signals, often with opposite slopes, so the module can detect a single-channel fault by correlation. This code is set when channel B is out of range, open, shorted or does not track channel A within tolerance. It supports brake-by-wire assist, regenerative braking blending and precise stop-lamp and cruise control. A fault can disable assist and cruise functions and set a warning lamp while base braking remains. No manufacturer documents this code publicly; NHTSA's EPS report lists C0043 in its J2012 table, and its brake study explains how the module uses the pedal sensor to read driver intent.
C0043 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyMedium, DIY possible
- Typical labor0.4 to 1.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of C0043
- Brake lights stay on or behave oddly
- Cruise control will not set
- ABS or brake warning lamp on
Common causes of C0043
- Most likelyPedal position sensor channel B out of range
- PossibleChannel A/B signals do not correlate
- Less likelyHarness or connector fault
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Brake pedal position sensor
What each part of C0043 means
| C | Chassis system: brakes, ABS, steering and suspension. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 43 | The exact fault in that area. |
What to do next
- Note C0043 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 C0043
What does C0043 mean?
C0043 means "Brake Pedal Position Sensor Circuit B". Covers circuit B of the brake pedal position sensor, the redundant second channel that the module cross-checks against channel A (C0042). It is a generic code, so it means the same on every make.
Is it safe to drive with C0043?
Drive gently and only to a workshop. With C0043 the car can go into limp mode (reduced power) to protect itself.
Will C0043 fail an emissions test?
C0043 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 C0043 to fix?
Difficulty: medium. A typical repair takes 0.4 to 1.5 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will C0043 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.