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.
Component Function Check
- INSPECTION START
Turn ignition switch OFF, and restart engine.
Does the engine start?
YES-1: With CONSULT: GO TO 2.
YES-2: Without CONSULT: GO TO 3.
NO: Go to "DIAGNOSIS PROCEDURE ".
- CHECK IGNITION SIGNAL FUNCTION
WITH CONSULT
- Perform "POWER BALANCE" in "ACTIVE TEST" mode with CONSULT.
- Check that each circuit produces a momentary engine speed drop.
Is the inspection result normal?
YES: INSPECTION END
NO: Go to "DIAGNOSIS PROCEDURE ".
- CHECK IGNITION SIGNAL FUNCTION
WITHOUT CONSULT
- Let engine idle.
- Read the voltage signal between ECM harness connector terminals under the following conditions with an oscilloscope.
ECM Voltage signal Cylinder + - Connector Terminal Connector Terminal 1 F111 12 E80 175 2 13 3 14 4 15 5 17 6 18 7 19 8 20 NOTE: The pulse cycle changes depending on rpm at idle.Is the inspection result normal?
YES: INSPECTION END
NO: Go to "DIAGNOSIS PROCEDURE ".
NO RELATED
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.