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
Ground Circuit
- Turn ignition switch off. Disconnect resistor and condenser harness connector. Disconnect power transistor harness connector. Using ohmmeter, check continuity between ignition coil terminal "b" to resistor and condenser terminal "d", and to power transistor terminal "i". See Fig 1 .
- Connect ohmmeter leads between power transistor terminal "h" and ground. See Fig 1 . Continuity should be present on all these terminals. If continuity is not present, check and repair wiring harness or connectors.
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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