Pedal position sensor: Diagnostics
If the sum of the voltages from the two pedal sensors deviates too greatly from 5V, then a fault must have occurred in one of the potentiometers or their circuits. In this case, the pedal position is not reliable.
Diagnostic trouble code P1530 or P1531 will be generated and the throttle control will go into limp-home mode.
If the two pedal sensor voltages were short-circuited to each other, the pedal sensor value would be 2.5V irrespective of the pedal position. This corresponds with the pedal being depressed half way. This fault cannot be detected by the sum voltage check so the control module sends short pulses on the control module input for sensor 2. If these pulses are detected on the control module input for sensor 1, then the sensors have been short-circuited.
Diagnostic trouble code P1532 will be generated and the throttle control will go into limp-home mode.
- In case of a pedal sensor malfunction, the maximum engine speed will be limited to 2200 RPM by fuel shut-off.
- The feel of the pedal is not affected in limp-home mode.