Self-Diagnosis and Troubleshooting

Self-Diagnosis

Fig. 11 Vehicle Maintenance Monitor (VMM) System Self Diagnosis Test Chart (Part 1 Of 2):

Fig. 11 Vehicle Maintenance Monitor (VMM) System Self Diagnosis Test Chart (Part 2 Of 2):

To enable self-diagnosis, depress and hold the Check and List select switches, then place ignition switch in On position. With the instrument cluster switch in the English mode, all diagnosis will be performed automatically in sequence. With the instrument cluster in the Metric mode, the Check select switch will have to be depressed to proceed to the next test. The display will indicate which components are defective or satisfactory. After completing diagnosis, depress Check and List select switches to exit diagnosis mode.

Troubleshooting
1. If a condition of no display or incorrect information exist, start engine and check the following:
a. On models less passive restraint check fuses 8 and 19 in fuse panel. On models with passive restraint, check fuses 2 and 8 in fuse panel. Replace any blown fuses.

Fig. 10 Vehicle Maintenance Monitor (VMM) System Wiring Schematic (Part 1 Of 2).:

Fig. 10 Vehicle Maintenance Monitor (VMM) System Wiring Schematic (Part 2 Of 2):

b. Using a suitable voltmeter, check terminal Nos. 1 and 5 of connector A. Voltmeter should indicate battery voltage, if not check for open circuit to fuse panel.
c. Connect a suitable ohmmeter between terminal Nos. 15 and 18 of connector A. Ohmmeter should indicate zero ohms. If a no display condition is present, replace monitor. If a incorrect information condition is present, refer to ``Self-Diagnosis." If reading is other than zero ohms, check for open circuit to ground.
d. With all doors closed, connect an ohmmeter between terminal Nos. 6, 7, 8 and 9 of connector A. Ohmmeter should indicate an infinite reading. If reading is other than infinite, check for short circuit to ground.
2. If monitor fails to change modes, disconnect electrical connector B, and proceed as follows:
a. With Check select switch depressed, connect ohmmeter between terminal Nos. 2 and 4 of connector B. If ohmmeter reading is zero ohms, proceed to step b. If ohmmeter reading is other than zero ohms, replace mode select switches.
b. With List select switch depressed, connect ohmmeter between terminal Nos. 2 and 3 of connector B. If ohmmeter reading is zero ohms, proceed to step c. If ohmmeter reading is other than zero ohms, replace mode select switches.
c. With Reset select switch depressed, connect ohmmeter between terminal Nos. 2 and 5 of connector B. Ohmmeter reading should be zero ohms. If ohmmeter reading is other than zero ohms, replace mode select switches.