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Test 1 No Start, Detects MCU Related Faults Only

Fig.8 - MCU System Wiring Circuit:






1. Turn ignition key off and disconnect vehicle harness from ignition module and horseshoe connector from coil. Connect an ohmmeter between circuit 11 and ground, Fig. 8. If resistance is 1,000 ohms or more, problem is not MCU related. If resistance is less than 1,000 ohms, proceed to next step.

2. Disconnect vehicle harness from MCU unit and check circuit 11 for short to ground by measuring resistance, Fig. 8. If resistance is 1,000 ohms or more, replace MCU unit. If resistance is less than 1,000 ohms, repair circuit 11.