Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1990 Infiniti M30FACTORY OEM SERVICE PROCEDURE
Ignition Coil Power Source
- Disconnect ignition coil relay harness connector. Turn ignition switch on. Using voltmeter, connect negative voltmeter lead to ground and check voltage in harness Black/White wire and White/Black wire. Battery voltage should be present on both terminals.
- If battery voltage is not present, check main harness connector, fusible link "G" in relay block, harness continuity between ignition coil and ignition switch, and harness continuity between ignition coil relay and battery. Repair or replace as necessary.
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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