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.
Ignition Coil Power Source
- Turn ignition off. Disconnect ignition coil harness connector. Turn ignition on. Connect DVOM negative lead to ground and proceed as follows:
- On I30, individually connect positive lead to each Red wire.
- On Q45, individually connect positive lead to each Black/White wire.
On all models, battery voltage should be present on each circuit.
- If battery voltage is not present, turn ignition off and proceed as follows:
- On I30, check harness continuity between ignition coil and fuse block. If continuity is present, check continuity of Black/Red wire between fuse block and ignition switch.
- On Q45, check 30-amp fuse in fuse box. If fuse is okay, check harness continuity between ignition coil and ignition switch, and harness continuity of White/Black wire between ignition switch and battery.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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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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