Pcm Code E31 - Shorted Map Sensor Circuit: Action

PCM turns on SERVICE ENGINE SOON light. PCM sets BARO equal to 92 kPa. PCM uses a substitute MAP sensor value based on engine RPM and throttle switch status.

NOTE: Test numbers refer to numbers on diagnostic chart.

If PCM parameter P.0.2 goes to 14-16 kPa with sensor unplugged, fault is at MAP sensor or sensor connector.
Checks for an open circuit from terminal "A" of sensor connector to PCM terminal A5 (ground). If ground is open, sensor cannot divide reference voltage to make signal voltage vary. Signal voltage is always high.