Action Taken

WARNING: This page is about a different car, the 1990 Cadillac Fleetwood and 1990 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.

ECM turns on SERVICE SOON light.
Turn off both air solenoids.
ECM uses a substitute MAP sensor value of 81.8 kPa with open throttle switch.
ECM uses a substitute MAP value from a table of substitute MAP versus RPM when throttle switch is closed.
ECM uses a substitute BARO value of 92.2 kPa.

The MAP sensor output voltage is a DC voltage that varies with MAP. As MAP decreases, voltage on circuit No. 432 decreases (low engine load, high engine vacuum). As MAP increases, voltage on circuit No. 432 increases (high engine load, low engine vacuum). Code E32 is designed to set when ECM detects a MAP sensor signal out of low limits (MAP signal at 16 kPa or less and MAP voltage at .08 volt or less).

NOTE: Test numbers refer to test numbers on diagnostic chart.

Test Number 1) Checks for sensor/ECM circuitry ability to respond to a 5-volt signal on MAP input. A reading of 106-109 kPa means wiring and ECM are okay.

Test Number 2) Check for 5-volt reference signal at sensor connector.

Test Number 3) Check for circuit No. 432 shorted to ground.

Test Number 4) Check for ECM ability to respond to a 5-volt signal voltage on MAP input.

Test Number 5) Fault is most likely at ECM connector or ECM. Before ECM is replaced, perform CHART C-1: ECM REPLACEMENT CHECK .