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
With CONSULT: GO TO 2.
YES
Without CONSULT: GO TO 3.
NO
Refer to Diagnosis Procedure .
- CHECK IGNITION SIGNAL FUNCTION-1
With CONSULT
- Perform "POWER BALANCE" in "ACTIVE TEST" mode of "ENGINE" with CONSULT.
- Check that each circuit produces a momentary engine speed drop.
Is the inspection result normal?
YES
INSPECTION END
NO
Refer to Diagnosis Procedure .
- CHECK IGNITION SIGNAL FUNCTION-2
Without CONSULT
- Let engine idle.
- Read the voltage signal between ECM harness connector terminals with an oscilloscope.
ECM
Voltage signal
+
-
Connector
Terminal
Connector
Terminal
F25
109
E16
162
106
105
103
NOTE: The pulse cycle changes depending on RPM at idle.
Is the inspection result normal?
YES
INSPECTION END
NO
Refer to Diagnosis Procedure .
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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