What does it mean?
P1275 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Accelerator Pedal Position Sensor 1 Circuit Malfunction .
Symptoms
- The MIL is on with a reduced power warning on the dash
- The engine only idles and does not react to the pedal
- Sharp loss of drive while the engine keeps running
- Limp mode with a fixed rev limit and no acceleration
- Cruise control disabled
- Intermittent surging or hesitation before the fault becomes permanent
Likely causes
- Signal wire open, shorted to ground or shorted to voltage somewhere in the pedal loom
- Missing or unstable 5 volt reference feeding the sensor 1 track
- High resistance in the sensor ground causing the signal to sit outside its window
- Damaged terminals in the pedal connector, often after the carpet or trim has been removed
- Worn track inside the pedal unit producing dropouts as the pedal moves
- Water in the footwell corroding the connector
- Failed pedal position sensor assembly
How to fix it
- Watch the sensor 1 percentage on live data while slowly pressing the pedal and look for dropouts to zero or jumps to full scale
- Check the pedal connector for moisture, corrosion, pin tension and correct latching
- With the ignition on, measure the 5 volt reference and the sensor ground at the pedal connector
- Back-probe the sensor 1 signal and confirm it rises and falls smoothly across the whole pedal travel
- With the connectors unplugged at both ends, test the signal wire for continuity, short to ground and short to voltage
- Wiggle the loom at the bulkhead and under the carpet while monitoring the data to expose an intermittent fault
- Replace the pedal assembly once the wiring is proven good, then carry out the pedal learn procedure and confirm normal response