ECD SYSTEM > ECM Power Source Circuit

for Preparation Click here


DESCRIPTION

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

WIRING DIAGRAM


A199012E02


INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.

1.CHECK HARNESS AND CONNECTOR (BATTERY - INTEGRATION RELAY)


    A200294E01

  1. Remove the integration relay from the engine room relay block.

  1. Measure the voltage according to the value(s) in the table below.

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    1A-1 - Body ground
    		Always
    		11 to 14 V

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Integration Relay)

  1. Reconnect the integration relay connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


2.CHECK HARNESS AND CONNECTOR (INTEGRATION RELAY - BODY GROUND)


    A200313E01

  1. Remove the integration relay from the engine room relay block.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    1C-6 - Body ground
    		Always
    		Below 1 Ω

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Integration Relay)

  1. Reconnect the integration relay connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.INSPECT INTEGRATION NO.1 RELAY (IG2 RELAY)


    A200366E01

  1. Remove the integration relay from the engine room relay block.

  1. Disconnect the integration relay connectors.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    1A-1 - 1B-7
    		When battery voltage absent
    		10 kΩ or higher
    When battery voltage applied to terminals 1D-12 and 1C-6
    		Below 1 Ω

    Text in Illustration 
    *1
    		Lower view of component without harness connected
    (Integration Relay)

  1. Reconnect the integration relay connectors.

  1. Reinstall the integration relay.
    Result 
    Result
    		Proceed to
    OK
    		A
    NG (w/ Entry and Start System)
    		B
    NG (w/o Entry and Start System)
    		C



B
Go to step 9

C
Go to step 7
A


4.CHECK HARNESS AND CONNECTOR (ECM - INTEGRATION RELAY)


    A200293E02

  1. Remove the integration relay from the engine room relay block.

  1. Disconnect the integration relay connector.

  1. Disconnect the ECM connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance (Check for Open):
    Tester Connection
    		Condition
    		Specified Condition
    1B-7 - A19-7 (IGSW)
    		Always
    		Below 1 Ω

    Standard Resistance (Check for Short):
    Tester Connection
    		Condition
    		Specified Condition
    1B-7 or A19-7 (IGSW) - Body ground
    		Always
    		10 kΩ or higher

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Integration Relay)
    *2
    		Front view of wire harness connector
    (to ECM)

  1. Reconnect the power source control ECU connector.

  1. Reconnect the integration relay connectors.

  1. Reinstall the integration relay.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


5.INSPECT INTEGRATION NO.1 RELAY (ECD RELAY)


    A200366E01

  1. Remove the integration relay from the engine room relay block.

  1. Disconnect the integration relay connectors.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    1A-1 - 1B-5
    1A-1 - 1B-6
    		When battery voltage absent
    		10 kΩ or higher
    When battery voltage applied to terminals 1B-8 and 1C-6
    		Below 1 Ω

    Text in Illustration 
    *1
    		Lower view of component without harness connected
    (Integration Relay)

  1. Reconnect the integration relay connectors.

  1. Reinstall the integration relay.



NG
REPLACE INTEGRATION NO.1 RELAY (Click here)
OK


6.INSPECT INTEGRATION NO.1 RELAY


    A200295E01

  1. Remove the integration relay from the engine room relay block.

  1. Disconnect the integration relay connectors.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    1A-1 - 1B-1
    1A-1 - 1E-7
    1A-1 - 1F-7
    1A-1 - 1F-8
    1A-1 - 1F-10
    1A-1 - 1F-11
    		When battery voltage absent
    		10 kΩ or higher
    When battery voltage applied to terminals 1B-8 and 1C-6
    		Below 1 Ω

    Text in Illustration 
    *1
    		Upper view of component without harness connected
    (Integration Relay)
    *2
    		Lower view of component without harness connected
    (Integration Relay)

  1. Reconnect the integration relay connectors.

  1. Reinstall the integration relay.



OK
Go to step 10

NG
REPLACE INTEGRATION NO.1 RELAY (Click here)

7.CHECK HARNESS AND CONNECTOR (BATTERY - IGNITION SWITCH - INTEGRATION RELAY)


    A200314E01

  1. Remove the integration relay from the engine room relay block.

  1. Disconnect the integration relay connector.

  1. Disconnect the ignition switch connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    1D-12 - D28-6 (IG2)
    		Always
    		Below 1 Ω
    D28-7 (AM2) - Battery positive terminal
    		Always
    		Below 1 Ω

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Integration Relay)
    *2
    		Front view of wire harness connector
    (to Ignition Switch)

  1. Reconnect the integration relay connectors.

  1. Reinstall the integration relay.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


8.INSPECT IGNITION SWITCH


    A200315E01

  1. Remove the ignition switch.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance (Check for Open):
    Tester Connection
    		Switch Condition
    		Specified Condition
    All terminals
    		LOCK
    		10 kΩ or higher
    2 - 3
    		ACC
    		Below 1 Ω
    2 - 3 - 4, 6 - 7
    		ON
    		Below 1 Ω
    1 - 2 - 4, 6 - 7 - 8
    		START
    		Below 1 Ω

    Text in Illustration 
    *1
    		Component without harness connected
    (Ignition Switch)

  1. Reconnect the integration relay connectors.

  1. Reinstall the integration relay.



NG
REPLACE IGNITION SWITCH (Click here)
OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE (Click here)  

9.CHECK HARNESS AND CONNECTOR (POWER SOURCE CONTROL ECU - INTEGRATION RELAY)


    A200316E01

  1. Remove the integration relay from the engine room relay block.

  1. Disconnect the integration relay connector.

  1. Disconnect the power source control ECU connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    1D-12 - D72-8 (IG2D)
    		Always
    		Below 1 Ω

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Integration Relay)
    *2
    		Front view of wire harness connector
    (to Power Source Control ECU)

  1. Reconnect the power source control ECU connector.

  1. Reconnect the integration relay connectors.

  1. Reinstall the integration relay.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

CHECK POWER SOURCE CONTROL ECU 

10.CHECK HARNESS AND CONNECTOR (ECM - INTEGRATION RELAY)


    A200293E03

  1. Remove the integration relay from the engine room relay block.

  1. Disconnect the integration relay connector.

  1. Disconnect the ECM connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance (Check for Open):
    Tester Connection
    		Condition
    		Specified Condition
    1B-8 - A19-22 (MREL)
    		Always
    		Below 1 Ω
    1B-5 - A19-1 (+B)
    		Always
    		Below 1 Ω
    1B-6 - A19-61 (+B1)
    		Always
    		Below 1 Ω

    Standard Resistance (Check for Short):
    Tester Connection
    		Condition
    		Specified Condition
    1B-8 or A19-22 (MREL) - Body ground
    		Always
    		10 kΩ or higher
    1B-5 or A19-1 (+B) - Body ground
    		Always
    		10 kΩ or higher
    1B-6 or A19-61 (+B1) - Body ground
    		Always
    		10 kΩ or higher

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Integration Relay)
    *2
    		Front view of wire harness connector
    (to ECM)

  1. Reconnect the power source control ECU connector.

  1. Reconnect the integration relay connectors.

  1. Reinstall the integration relay.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE (Click here)