Pcm Code E031, Shorted Map Sensor Circuit: Action

WARNING: This page is about a different car, the 1992 Cadillac Seville and 1992 Cadillac Eldorado. However, it is still accessible from the selected car via links, so may be relevant.

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

NOTE: Test numbers refer to numbers on diagnostic chart.

If PCM parameter ED02 goes to 14-16 kPa with sensor unplugged, fault is at MAP sensor or sensor connector.
This 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.