Pedal position sensor: Diagnostics
If the total voltage from the two pedal position sensors differs too much from 5V a fault has occurred in one of the potentiometers or in their circuits. The pedal position in other words is not to be trusted.
Diagnostic trouble code P1530 or P1531 will be generated and the throttle control goes into limp-home mode.
If the voltages from the two pedal position sensors are shorted to each other, the pedal sensor voltage will be 2.5 V irrespective of the pedal position, which corresponds to a pedal pressed halfway down. This fault is not covered by the total voltage check and therefore the control module sends out short pulses on the input for sensor 2. If these pulses are detected on the input for sensor 1, a short-circuit has occurred between the sensors.
Diagnostic trouble code P1532 is generated and the throttle valve control goes into limp -home mode.
- If a pedal position sensor fault occurs, maximum engine speed will be limited to 2200 RPM through fuel shut-off.
- Pedal sensitivity is not changed in limp-home mode.