What P2135 means
Throttle/Pedal Position Sensor/Switch A/B Voltage Correlation
How to diagnose
- Read freeze frame data. When P2135 set, your ECU snapshotted every sensor at that moment. This tells you what the car was doing when the fault triggered — RPM, load, coolant temp, throttle position, fuel trims. Almost always enough info to figure out the cause without further testing.
- Check for related codes. If you have P2135 plus other codes, fix the earliest one in the chain first — a single root cause often triggers multiple codes.
- Cheap fixes first. For most codes, the order is: inspect connectors + wiring (free), check for vacuum leaks (cheap), replace sensor (moderate), replace mechanical part (expensive). Follow that ladder before dropping money on parts.
Manufacturer-specific descriptions
Different manufacturers use P2135 for slightly different failure modes:
| AUDI | Accelerator Pedal Position (APP) assembly failure, Powertrain Control Module (PCM) failure, Throttle Position Sensor (TPS) failure, Wiring issue |
| BMW | Throttle/Pedal Position Sensor/Switch "A" / "B" Voltage Correlation |
| FIAT | between sensor ped. acc. 1 and sensor ped. acc. 2 Electrical Wiring Fault |
| HONDA | Throttle Position (TP) Sensor 1/2 Incorrect Voltage Correlation |
| MITSUBISHI | TPS(main/sub) correlation |
Read P2135 on your own car
DIY Fix My Car reads P2135 plus 25,000+ other DTC codes with manufacturer-specific descriptions. Includes freeze frame data, likely fix parts, and AI mechanic chat. Download free.