Engine Control Module: Testing and Inspection

Fig. 16 Output Signal Diagnosis Chart. Part 1 of 2:

Fig. 16 Output Signal Diagnosis Chart. Part 2 of 2:

Fig. 17 ECU terminal identification. Exc. Conquest w/intercooler:

Fig. 18 ECU terminal identification. Conquest w/intercooler:

Using output signal diagnosis chart, Fig. 16 , connect voltmeter to diagnostic connector, as specified in ``Terminal Location of Computer'' column in diagnostic chart. Check voltage at each terminal, ensuring tests are made under conditions specified.
On 1984 models, when checking the ISC motor position switch, if the ignition switch is turned on for more than 15 seconds, the readings will drop to 1 volt or less, then return to 6 to 13 volts. When checking the ISC motor for extension and retraction, the indication for satisfactory operation will be present for a very short time. If indication is difficult to read, turn A/C switch on and off several times while observing meter. If needle swings, components are satisfactory.