What does it mean?
P1248 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Accelerator Pedal Position Sensor Correlation .
Symptoms
- The MIL is on, often with a reduced power warning
- The engine drops into limp mode with limited rpm and no pedal response
- Sudden hesitation or momentary loss of drive during acceleration
- Idle speed higher than normal or stuck at a fixed value
- The fault reappears mainly when the pedal is pressed quickly or held part way
Likely causes
- One pedal track drifting because of a worn or dirty resistive surface
- High resistance in one of the two signal circuits caused by corroded terminals
- Shared reference or ground circuit with a poor connection, offsetting only one signal
- Chafed pedal harness creating an intermittent short or crosstalk between the two signals
- Moisture in the pedal connector from a footwell leak
- Mechanical binding of the pedal, a trapped floor mat or a bent pedal arm holding one track off its rest position
- Pedal module replaced without carrying out the required learn procedure
How to fix it
- Graph both pedal signals on the scan tool at the same time and press the pedal slowly through full travel; the tracks must move together and both must return to rest
- Confirm the pedal returns fully with no mat, mat clip or trim blocking it
- Check the pedal connector for moisture and corrosion, and check terminal tension on both signal pins
- Measure the reference voltage and ground at the pedal with the key on, then repeat with the pedal pressed
- Perform a voltage drop test on the shared ground circuit, since a bad ground can offset one track only
- Wiggle the pedal loom at the bulkhead while watching live data to expose an intermittent
- Replace the pedal position sensor assembly when the wiring tests good, then run the pedal learn routine and confirm both signals track correctly