Ecd System Ecm Power Source Circuit


DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK ECM (+B VOLTAGE)

CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND)

CHECK ECM (IGSW VOLTAGE)

INSPECT FUSE (IGN)

INSPECT IGNITION SWITCH ASSEMBLY

CHECK ECM (MREL VOLTAGE)

INSPECT FUSE (EFI)

CHECK INTEGRATION NO.1 RELAY (MAIN RELAY)

CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY [MAIN RELAY] - ECM AND BODY GROUND)

ECD SYSTEM - ECM Power Source Circuit


DESCRIPTION

When the ignition switch is turned ON, the battery voltage is applied to terminal IGSW of the ECM. The ECM "MREL" output signal causes current to flow to the MAIN relay coil, closing the contacts of the EFI relay and supplying power to terminal +B of the ECM.

WIRING DIAGRAM


Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.5L-E Engine Control System.Ecd System.Ecd System Ecm Power Source Circuit


INSPECTION PROCEDURE

1.CHECK ECM (+B VOLTAGE)
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.5L-E Engine Control System.Ecd System.Ecd System Ecm Power Source Circuit

  1. Turn the ignition switch ON.

  1. Measure the voltage of the ECM connector.

    Standard voltage:
    Tester Connection
    		Specified Condition
    E23-12 (+B) - E20-14 (E1)
    		9 to 14 V


OK
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
NG


2.CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND)
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.5L-E Engine Control System.Ecd System.Ecd System Ecm Power Source Circuit

  1. Disconnect the E20 ECM connector.

  1. Measure the resistance of the wire harness side connector.

    Standard resistance:
    Tester Connection
    		Specified Condition
    E20-14 (E1) - Body ground
    		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.CHECK ECM (IGSW VOLTAGE)
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.5L-E Engine Control System.Ecd System.Ecd System Ecm Power Source Circuit

  1. Turn the ignition switch ON.

  1. Measure the voltage of the ECM connector.

    Standard voltage:
    Tester Connection
    		Specified Condition
    E23-14 (IGSW) - E20-14 (E1)
    		9 to 14 V


OK
Go to step 6
NG


4.INSPECT FUSE (IGN)
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.5L-E Engine Control System.Ecd System.Ecd System Ecm Power Source Circuit

  1. Remove the IGN fuse from the instrument panel junction block.

  1. Measure the resistance of the IGN fuse.

    Standard resistance:
    Tester Connection
    		Specified Condition
    IGN fuse
    		Below 1 Ω


NG
CHECK FOR SHORT IN ALL HARNESSES AND COMPONENTS CONNECTED TO FUSE
OK


5.INSPECT IGNITION SWITCH ASSEMBLY
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.5L-E Engine Control System.Ecd System.Ecd System Ecm Power Source Circuit

  1. Disconnect the I8 ignition switch connector.

  1. Measure the resistance of the ignition switch.

    Standard resistance:
    Tester Connection
    		Switch Condition
    		Specified Condition
    5 (AM2) - 6 (IG2)
    		LOCK
    		10 kΩ or higher
    5 (AM2) - 6 (IG2)
    		ON
    		Below 1 Ω


NG
REPLACE IGNITION SWITCH ASSEMBLY
OK

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

6.CHECK ECM (MREL VOLTAGE)
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.5L-E Engine Control System.Ecd System.Ecd System Ecm Power Source Circuit

  1. Turn the ignition switch ON.

  1. Measure the voltage of the ECM connector.

    Standard voltage:
    Tester Connection
    		Specified Condition
    E23-3 (MREL) - E20-14 (E1)
    		9 to 14 V


NG
REPLACE ECM
OK


7.INSPECT FUSE (EFI)
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.5L-E Engine Control System.Ecd System.Ecd System Ecm Power Source Circuit

  1. Remove the EFI fuse from the engine room junction block.

  1. Measure the resistance of the EFI fuse.

    Standard resistance:
    Tester Connection
    		Specified Condition
    EFI fuse
    		Below 1 Ω


NG
CHECK FOR SHORT IN ALL HARNESSES AND COMPONENTS CONNECTED TO FUSE
OK


8.CHECK INTEGRATION NO.1 RELAY (MAIN RELAY)
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.5L-E Engine Control System.Ecd System.Ecd System Ecm Power Source Circuit

  1. Disconnect the 1J integration relay connector from the engine room junction block (Toyota Fortuner RM0000014TJ00VX_01_0001.html).

  1. Measure the voltage of the integration relay.

    Standard voltage:
    Tester Connection
    		Condition
    		Specified Condition
    1J-4 - Body ground
    		Ignition switch ON
    		10 to 14 V


NG
REPLACE INTEGRATION NO.1 RELAY
OK


9.CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY [MAIN RELAY] - ECM AND BODY GROUND)
Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.5L-E Engine Control System.Ecd System.Ecd System Ecm Power Source Circuit

  1. Disconnect the 1J integration relay connector from the engine room junction block (Toyota Fortuner RM0000014TJ00VX_01_0001.html).

  1. Disconnect the E23 ECM connector.

  1. Measure the resistance of the wire harness side connectors.

    Standard resistance:
    Tester Connection
    		Specified Condition
    1J-2 - E23-3 (MREL)
    		Below 1 Ω
    1J-4 - E23-12 (+B)
    		Below 1 Ω
    1J-3 - Body ground
    		Below 1 Ω
    1J-2 or E23-3 (MREL) - Body ground
    		10 kΩ or higher
    1J-4 or E23-12 (+B) - Body ground
    		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPAIR OR REPLACE HARNESS OR CONNECTOR (TERMINAL +B OF ECM - BATTERY)