ECM Power Source Circuit: Procedure

1. Turn the engine switch on (IG).
   Fig 1: Identifying ECM Connector Pin Terminal

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

   Standard voltage

   Tester Connection	Switch Condition	Specified Condition
   A13-2 (+B) - E3-1 (E1)	Engine switch on (IG)	11 to 14 V
   A13-1 (+B2) - E3-1 (E1)	Engine switch on (IG)	11 to 14 V

OK → See step   10 

NG: Go to next step 

1. Disconnect the E3 ECM connector.
   Fig 2: Identifying Terminal E1 Of E3 ECM Connector

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

   Standard resistance (Check for open)

   Tester Connection	Condition	Specified Condition
   E3-1 (E1) - Body ground	Always	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Turn the engine switch on (IG).
   Fig 3: Inspecting ECM (IGSW Voltage)

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

   Standard voltage

   Tester Connection	Switch Condition	Specified Condition
   A14-8 (IGSW) - E3-1 (E1)	Engine switch on (IG)	11 to 14 V

OK → See step   6 

NG: Go to next step 

1. Remove the ECU-IG fuse from the engine room No. 2 junction block.
   Fig 4: Identifying ECU-IG Fuse

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

   Standard resistance

   Tester Connection	Condition	Specified Condition
   ECU-IG	Always	Below 1 Ω

NG → CHECK FOR SHORT IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

OK: Go to next step 

1. Remove the IG2 relay from the engine room No. 2 junction block.
   Fig 5: Identifying IG2 Relay

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

   Standard resistance

   Tester Connection	Condition	Specified Condition
   3 - 5	When no battery voltage applied to terminals 1 and 2	10 kΩ or higher
   3 - 5	When battery voltage applied to terminals 1 and 2	Below 1 Ω

NG → See step   11 

OK → See step   12 

1. Turn the engine switch on (IG).
   Fig 6: Inspecting ECM (MREL Voltage)

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

   Standard voltage

   Tester Connection	Switch Condition	Specified Condition
   A14-3 (MREL) - E3-1 (E1)	Engine switch on (IG)	11 to 14 V

NG → See step   13 

OK: Go to next step 

1. Remove the EFI MAIN2 fuse from the engine room No. 2 relay block.
   Fig 7: Identifying Engine Room No. 2 Relay Block And EFI MAIN2 Fuse

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

   Standard resistance

   Tester Connection	Condition	Specified Condition
   EFI MAIN2	Always	Below 1 Ω

NG → CHECK FOR SHORT IN ALL HARNESSES AND CONNECTORS CONNECTED TO FUSE AND REPLACE FUSE 

OK: Go to next step 

1. Remove the EFI MAIN2 relay from the engine room No. 2 relay block.
   Fig 8: Identifying Relay Terminals

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

   Standard resistance

   Tester Connection	Condition	Specified Condition
   3 - 5	When no battery voltage applied to terminals 1 and 2	10 kΩ or higher
   	When battery voltage applied to terminals 1 and 2	Below 1 Ω

NG → See step   14 

OK: Go to next step 

Fig 9: Checking Harness And Connector (EFI Relay (EFI MAIN2) - ECM, Body Ground)

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1. Check the harness and the connectors between the integration relay and the ECM.
   1. Remove the EFI MAIN2 relay from the engine room No. 2 relay block.
   2. Disconnect the A14 ECM connector.
   3. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open)

      Tester Connection	Condition	Specified Condition
      EFI MAIN2 relay (1) - A14-3 (MREL)	Always	Below 1 Ω

      Standard resistance (Check for short)

      Tester Connection	Condition	Specified Condition
      EFI MAIN2 relay (1) or A14-3 (MREL) - Body ground	Always	10 kΩ or higher

2. Check the harness and the connectors between the EFI MAIN2 relay and body ground.
   1. Remove the EFI MAIN2 relay from the engine room No. 2 relay block.
   2. Measure the resistance according to the value(s) in the table below.

      Standard resistance (Check for open)

      Tester Connection	Condition	Specified condition
      EFI MAIN2 relay (2) - Body ground	Always	Below 1 Ω

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → CHECK AND REPAIR HARNESS OR CONNECTOR (TERMINAL +B OF ECM - BATTERY POSITIVE TERMINAL)