ECM Power Source Circuit: Wiring Diagram

1. Turn the ignition switch ON.
2. Measure the voltage of the ECM connectors.

Standard voltage 

OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOMS TABLE 

Fig 2: Measuring Voltage Of ECM Connectors

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NG: Go To Next Step 

OK: Go To Next Step 

1. Disconnect the E6 ECM connector.
2. Measure the resistance of the wire harness side connector.

Standard resistance 

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

Fig 3: Measuring Resistance Of Wire Harness Side Connector

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1. Turn the ignition switch ON.
2. Measure the voltage of the ECM connectors.

Standard voltage 

NG: GO TO STEP   6 

Fig 4: Measuring Voltage Of ECM Connectors

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OK: Go to next step 

1. Remove the IGN fuse from the cowl side junction block RH.
2. Measure the resistance of the IGN fuse.

Standard resistance: Below 1 Ω 

NG: CHECK FOR SHORT IN ALL HARNESS AND COMPONENTS CONNECTED TO IGN FUSE, AND REPLACE IGN FUSE 

Fig 5: Inspecting Fuse (IGN)

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1. Remove the I18 ignition switch connector.
2. Measure the resistance of the ignition switch.

Standard resistance 

NG: REPLACE IGNITION SWITCH ASSEMBLY 

Fig 6: Identifying I18 Ignition Switch Connector

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OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (BATTERY - IGNITION SWITCH, IGNITION SWITCH - ECM) 

1. Turn the ignition switch ON.
2. Measure the voltage of the ECM connectors.

Standard voltage 

NG: REPLACE ECM 

Fig 7: Measuring Voltage Of ECM Connectors

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OK: Go To Next Step 

1. Remove the EFI OR ECD NO. 1 fuse from the engine room junction block.
2. Measure the resistance of the EFI OR ECD NO. 1 fuse.

Standard resistance: Below 1 Ω 

NG: CHECK FOR SHORT IN ALL HARNESS AND COMPONENTS CONNECTED TO EFI OR ECD NO. 1 FUSE, AND REPLACE EFI OR ECD FUSE 

Fig 8: Removing EFI Or ECD Fuse From Engine Room Junction Block

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OK: Go To Next Step 

1. Remove the EFI relay from the engine room relay block.
2. Measure the resistance of the EFI relay.

Standard resistance 

NG: REPLACE EFI RELAY 

Fig 9: Inspecting EFI Relay

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OK: Go To Next Step 

1. Check harness and connector (ELECTRONIC CIRCUIT INSPECTION PROCEDURE ).

OK: REPAIR OR REPLACE HARNESS OR CONNECTOR 

NG: CHECK AND REPLACE HARNESS OR CONNECTOR (TERMINAL +B OF ECM - POSITIVE BATTERY TERMINAL)