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
- INSPECT ECU TERMINAL VOLTAGE (+B TERMINAL)
- Disconnect the TCM connector.
- Turn the engine switch on (IG).
- Measure the voltage according to the value(s) in the table below.
Standard voltage
VOLTAGE SPECIFICATIONTester Connection Specified Condition +B (B40-18) - E1 (B40-8) 9 to 14 V
OK: CHECK FOR INTERMITTENT PROBLEMS
NG: Go to Next Step
- CHECK HARNESS AND CONNECTOR (TCM - BODY GROUND)
- Measure the resistance according to the value(s) in the table below.
Standard resistance
RESISTANCE SPECIFICATIONTester Connection Specified Condition E1 (B40-8) - Body ground Below 1 Ω - Reconnect the TCM connector.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (TCM - BODY GROUND)
OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (TCM - EFI RELAY)
- Measure the resistance according to the value(s) in the table below.
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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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