HYBRID CONTROL SYSTEM ECU Power Source Circuit

DESCRIPTION

If the power switch is on (IG), the hybrid vehicle control ECU assembly applies current to the MREL terminal to turn the IGCT NO.1 relay on. This supplies power to the +B1 and +B2 terminals.

PROCEDURE

1. Click here

   CHECK HYBRID VEHICLE CONTROL ECU ASSEMBLY (+B1, +B2 VOLTAGE)

   
   

   1. Turn the power switch on (IG).

   2. 

      *a	Component with harness connected (Hybrid Vehicle Control ECU Assembly)

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

      Standard Voltage
      Tester Connection Condition Specified Condition G92-4 (+B1) - Body ground Power switch on (IG) 11 to 14 V G93-3 (+B2) - Body ground Power switch on (IG) 11 to 14 V

   3. Turn the power switch off.

      Result
      Proceed to OK NG

   
   
   • OKClick here
   • NGClick here
2. Click here

   CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU ASSEMBLY - BODY GROUND)

   
   

   1. Disconnect the A76, G92 and G93 hybrid vehicle control ECU assembly connectors.

   2. 

      *a	Rear view of wire harness connector (to Hybrid Vehicle Control ECU Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition G92-6 (E1) - Body ground Power switch off Below 1 Ω G93-6 (E12) - Body ground Power switch off Below 1 Ω A76-2 (E01) - Body ground Power switch off Below 1 Ω G92-2 (E02) - Body ground Power switch off Below 1 Ω

   3. Reconnect the A76, G92 and G93 hybrid vehicle control ECU assembly connectors.

      Result
      Proceed to OK NG

   
   
   • OK

     GO TO PROBLEM SYMPTOMS TABLEClick here

   • NG

     REPAIR OR REPLACE HARNESS OR CONNECTOR

3. Click here

   CHECK HYBRID VEHICLE CONTROL ECU ASSEMBLY (MREL VOLTAGE)

   
   

   1. Turn the power switch on (IG).

   2. 

      *a	Component with harness connected (Hybrid Vehicle Control ECU Assembly)

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

      Standard Voltage
      Tester Connection Condition Specified Condition A77-1 (MREL) - Body ground Power switch on (IG) 11 to 14 V

   3. Turn the power switch off.

      Result
      Proceed to OK NG

   
   
   • OKClick here
   • NG

     REPLACE HYBRID VEHICLE CONTROL ECU ASSEMBLYClick here

4. Click here

   CHECK FUSE (PM-IGCT)

   
   
   1. 

      *1	No. 2 Luggage Room Relay Block
      *2	PM-IGCT Fuse

      Remove the PM-IGCT fuse from the No. 2 luggage room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition PM-IGCT fuse terminals Always Below 1 Ω

   3. Install the PM-IGCT fuse.

      Result
      Proceed to OK NG

   
   
   • OKClick here
   • NGClick here
5. Click here

   CHECK FUSE (IGCT NO.1)

   
   
   1. 

      *1	No. 2 Luggage Room Relay Block
      *2	IGCT NO.1 Fuse

      Remove the IGCT NO.1 fuse from the No. 2 luggage room relay block.

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

      Standard Resistance
      Tester Connection Condition Specified Condition IGCT NO.1 fuse terminals Always Below 1 Ω

   3. Install the IGCT NO.1 fuse.

      Result
      Proceed to OK NG

   
   
   • OKClick here
   • NGClick here
6. Click here

   INSPECT RELAY (IGCT NO.1)

   
   
   1. 

      *1	No. 2 Luggage Room Relay Block
      *2	IGCT NO.1 Relay

      Remove the IGCT NO.1 relay from the No. 2 luggage room relay block.

   2. 

      *1	IGCT NO.1 Relay

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

      Standard Resistance
      Tester Connection Condition Specified Condition 3 - 5 Auxiliary battery voltage not applied between terminals 1 and 2 10 kΩ or higher Auxiliary battery voltage applied between terminals 1 and 2 Below 1 Ω

   3. Install the IGCT NO.1 relay.

      Result
      Proceed to OK NG

   
   
   • OKClick here
   • NG

     REPLACE RELAY (IGCT NO.1)

7. Click here

   CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU ASSEMBLY - NO. 2 LUGGAGE ROOM RELAY BLOCK)

   
   

   1. Disconnect the G92 and G93 hybrid vehicle control ECU assembly connectors.

   2. 

      *1	No. 2 Luggage Room Relay Block
      *2	PM-IGCT Fuse

      Remove the PM-IGCT fuse from the No. 2 luggage room relay block.

   3. 

      *1	No. 2 Luggage Room Relay Block	*2	PM-IGCT Fuse
      *a	Rear view of wire harness connector (to Hybrid Vehicle Control ECU Assembly)	-	-

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

      Standard Resistance
      Tester Connection Condition Specified Condition G92-4 (+B1) - 2 (PM-IGCT fuse) Power switch off Below 1 Ω G93-3 (+B2) - 2 (PM-IGCT fuse) Power switch off Below 1 Ω

   4. Reconnect the G92 and G93 hybrid vehicle control ECU assembly connectors.

   5. Install the PM-IGCT fuse.

      Result
      Proceed to OK NG

   
   
   • OKClick here
   • NG

     REPAIR OR REPLACE HARNESS OR CONNECTOR

8. Click here

   CHECK HARNESS AND CONNECTOR (NO. 2 LUGGAGE ROOM RELAY BLOCK)

   
   
   1. 

      *1	No. 2 Luggage Room Relay Block
      *2	PM-IGCT Fuse
      *3	IGCT NO.1 Fuse
      *4	IGCT NO.1 Relay

      Remove the IGCT NO.1 fuse, PM-IGCT fuse and IGCT NO.1 relay from the No. 2 luggage room relay block.

   2. 

      *1	No. 2 Luggage Room Relay Block
      *2	PM-IGCT Fuse
      *3	IGCT NO.1 Fuse
      *4	IGCT NO.1 Relay

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

      Standard Resistance
      Tester Connection Condition Specified Condition 3 (IGCT NO.1 relay) - 2 (IGCT NO.1 fuse) Power switch off Below 1 Ω 5 (IGCT NO.1 relay) - 1 (PM-IGCT fuse) Power switch off Below 1 Ω

   3. Install the IGCT NO.1 fuse, PM-IGCT fuse and IGCT NO.1 relay.

      Result
      Proceed to OK NG

   
   
   • OKClick here
   • NG

     REPAIR OR REPLACE HARNESS OR CONNECTOR

9. Click here

   CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU ASSEMBLY - NO. 2 LUGGAGE ROOM RELAY BLOCK)

   
   

   1. Disconnect the A77 hybrid vehicle control ECU assembly connector.

   2. 

      *1	No. 2 Luggage Room Relay Block
      *2	IGCT NO.1 Relay

      Remove the IGCT NO.1 relay from the No. 2 luggage room relay block.

   3. 

      *1	No. 2 Luggage Room Relay Block	*2	IGCT NO.1 Relay
      *a	Rear view of wire harness connector (to Hybrid Vehicle Control ECU Assembly)	-	-

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

      Standard Resistance
      Tester Connection Condition Specified Condition A77-1 (MREL) - 1 (IGCT NO.1 relay) Power switch off Below 1 Ω A77-1 (MREL) or 1 (IGCT NO.1 relay) - Body ground and other terminals Power switch off 10 kΩ or higher

   4. Install the IGCT NO.1 relay.

   5. Reconnect the A77 hybrid vehicle control ECU assembly connector.

      Result
      Proceed to OK NG

   
   
   • OKClick here
   • NG

     REPAIR OR REPLACE HARNESS OR CONNECTOR

10. Click here

    CHECK HARNESS AND CONNECTOR (NO. 2 LUGGAGE ROOM RELAY BLOCK - BODY GROUND)

    
    
    1. 

       *1	No. 2 Luggage Room Relay Block
       *2	IGCT NO.1 Relay

       Remove the IGCT NO.1 relay from the No. 2 luggage room relay block.

    2. 

       *1	No. 2 Luggage Room Relay Block
       *2	IGCT NO.1 Relay

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

       Standard Resistance
       Tester Connection Condition Specified Condition 2 (IGCT NO.1 relay) - Body ground Power switch off Below 1 Ω

    3. Install the IGCT NO.1 relay.

       Result
       Proceed to OK NG

    
    
    • OK

      CHECK FOR INTERMITTENT PROBLEMSClick here

    • NG

      REPAIR OR REPLACE HARNESS OR CONNECTOR

11. Click here

    CHECK HARNESS AND CONNECTOR (HYBRID VEHICLE CONTROL ECU ASSEMBLY - NO. 2 LUGGAGE ROOM RELAY BLOCK)

    
    
    1. 

       *1	No. 2 Luggage Room Relay Block
       *2	PM-IGCT Fuse

       Remove the PM-IGCT fuse from the No. 2 luggage room relay block.

    2. Disconnect the G92 and G93 hybrid vehicle control ECU assembly connectors.

    3. 

       *1	No. 2 Luggage Room Relay Block	*2	PM-IGCT Fuse
       *a	Rear view of wire harness connector (to Hybrid Vehicle Control ECU Assembly)	-	-

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

       Standard Resistance
       Tester Connection Condition Specified Condition G92-4 (+B1) or 2 (PM-IGCT fuse) - Body ground and other terminals Power switch off 10 kΩ or higher G93-3 (+B2) or 2 (PM-IGCT fuse) - Body ground and other terminals Power switch off 10 kΩ or higher

    4. Reconnect the G92 and G93 hybrid vehicle control ECU assembly connectors.

    5. Install the PM-IGCT fuse.

       Result
       Proceed to OK NG

    
    
    • OK

      REPLACE FUSE (PM-IGCT)

    • NGClick here
12. Click here

    CHECK HARNESS AND CONNECTOR (NO. 2 LUGGAGE ROOM RELAY BLOCK)

    
    
    1. 

       *1	No. 2 Luggage Room Relay Block
       *2	PM-IGCT Fuse
       *3	IGCT NO.1 Fuse
       *4	IGCT NO.1 Relay

       Disconnect the IGCT NO.1 fuse, PM-IGCT fuse and IGCT NO.1 relay from the No. 2 luggage room relay block.

    2. 

       *1	No. 2 Luggage Room Relay Block
       *2	PM-IGCT Fuse
       *3	IGCT NO.1 Fuse
       *4	IGCT NO.1 Relay

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

       Table 2. Standard Resistance:

       Tester Connection	Condition	Specified Condition
       3 (IGCT NO.1 relay) or 2 (IGCT NO.1 fuse) - Body ground and other terminals	Power switch off	10 kΩ or higher
       5 (IGCT NO.1 relay) or 1 (PM-IGCT fuse) - Body ground and other terminals	Power switch off	10 kΩ or higher

    3. Install the IGCT NO.1 fuse, PM-IGCT fuse and IGCT NO.1 relay.

       Result
       Proceed to OK NG

    
    
    • OK

      REPLACE FUSE (IGCT NO.1)

    • NGClick here
13. Click here

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    Result
    Proceed to NEXT

    
    
    • NEXT

      REPLACE FUSE (PM-IGCT)

14. Click here

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    Result
    Proceed to NEXT

    
    
    • NEXT

      REPLACE FUSE (IGCT NO.1)