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 ECM (+B VOLTAGE)
- Turn the ignition switch ON
- Measure the voltage of the ECM connectors.
Standard voltage
STANDARD VOLTAGETester Connection Specified Condition +B (E9-1) - E1 (E7-1) 9 to 14 V
OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
NG: Go to Next Step
- CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND)
- Disconnect the E7 ECM connector.
- Measure the resistance of the wire harness side connector.
Standard resistance
STANDARD RESISTANCETester Connection Specified Condition E1 (E7-1) - Body ground Below 1 Ω
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
OK: Go to Next Step
- CHECK ECM (IGSW VOLTAGE)
- Turn the ignition switch ON.
- Measure the voltage of the ECM connectors.
Standard voltage
STANDARD VOLTAGETester Connection Specified Condition IGSW (E9-9) - E1 (E7-1) 9 to 14 V
OK: Go to step 6
NG: Go to Next Step
- INSPECT FUSE (IGN)
- Remove the IGN fuse from the driver side J/B.
- Measure the resistance of the IGN fuse.
Standard resistance:
Below 1 Ω
NG: REPLACE FUSE
OK: Go to Next Step
- INSPECT IGNITION SWITCH ASSEMBLY
- Remove the lower finish panel.
- Disconnect the 118 ignition switch connector.
- Measure the resistance of the ignition switch.
Standard resistance
STANDARD RESISTANCESwitch position Tester Connection Specified Condition LOCK All Terminals 10 kΩ or higher ACC 2-3 Below 1 Ω ON 2-3, 2-4 6-7 START 1-2, 2-4 6-7, 7-8 - Reconnect the ignition switch connector.
NG: REPLACE IGNITION SWITCH ASSEMBLY
OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - IGNITION SWITCH, IGNITION SWITCH - ECM)
- CHECK ECM (MREL VOLTAGE)
- Turn the ignition switch ON.
- Measure the voltage of the ECM connectors.
Standard voltage
STANDARD VOLTAGETester Connection Specified Condition MREL (E9-8) - E1 (E7-1) 9 to 14 V
NG: REPLACE ECM
OK: Go to Next Step
- INSPECT FUSE (EFI)
- Remove the EFI fuse from the engine room R/B.
- Measure the resistance of the EFI fuse.
Standard resistance:
Below 1 Ω
NG: REPLACE FUSE
OK: Go to Next Step
- INSPECT EFI RELAY (Marking: EFI)
- Remove the EFI relay from the engine room junction block.
- Measure the resistance of the EFI relay.
Standard resistance
STANDARD RESISTANCETerminal Connection Specified Condition 3-5 10 kΩ or higher 3-5 Below 1 Ω (when battery voltage is applied to terminals 1 and 2) - Reinstall the EFI relay.
NG: REPLACE EFI RELAY
OK: Go to Next Step
- CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND)
- Disconnect the E9 ECM connector.
- Measure the resistance between the wire harness side connector and body ground.
Standard resistance
STANDARD RESISTANCETester Connection Specified Condition MREL (E9-8) - Body ground Below 1 Ω - Reconnect the ECM connector.
OK: REPAIR OR REPLACE HARNESS OR CONNECTOR
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
NG: CHECK FOR INTERMITTENT PROBLEMS
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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