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.
Inspection Procedure
- CHECK TCM (POWER SOURCE, BODY GROUND)
- Disconnect the A12 and E5 TCM connectors.
- Turn the engine switch on (IG).
- Measure the voltage of the wire harness side connectors.
Standard Voltage
VOLTAGE SPECIFICATIONTester Connection Switch Condition Specified Condition A12-6 (+B) - E5-7 (E1) Engine switch on (IG) 11 to 14 V - Turn the engine switch off.
- Measure the resistance of the wire harness side connector.
Standard Resistance
RESISTANCE REFERENCETester Connection Condition Specified Condition ES-7 (E1) - Body ground Always Below 1 Ω
NG: CHECK HARNESS AND CONNECTOR (TCM EFI MAIN NO. 2 RELAY, BODY GROUND)
OK: GO TO ECM POWER SOURCE CIRCUIT (ENGINE CONTROL SYSTEM / SFI SYSTEM) (See ECM POWER SOURCE CIRCUIT )
Use the Manual With the Right Hardware
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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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