Fuel Pump Control Circuit: Wiring Diagram

Fig 1: Identifying Fuel Pump Control Circuit Wiring Diagram (2 Of 2)

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

This troubleshooting procedure is based on the premise that the engine is started. If the engine is not started, proceed to PROBLEM SYMPTOMS TABLE .

1. CHECK FUEL PUMP OPERATION 
   1. Check if there is pressure in the fuel inlet hose.

      HINT:

      If there is fuel pressure, you will hear the sound of fuel flowing.

   OK : Go to step   12 

   NG : GO TO NEXT STEP. 

2. PERFORM ACTIVE TEST (OPERATE C/OPN RELAY) 
   1. Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
   2. Turn the engine switch on (IG) and turn the tester ON.
   3. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / FUEL PUMP / SPD.
   4. Check the relay operation while operating it using the tester.

      OK: 

      Operating noise can be heard from the relay. 

   OK : Go to step   8 

   NG : GO TO NEXT STEP. 

3. INSPECT ECM POWER SOURCE CIRCUIT 

   NG : CHECK ENGINE TO DETERMINE CAUSE OF LOW COMPRESSION 

   OK : GO TO NEXT STEP. 

4. INSPECT FUSE (F/PUMP) 
   1. Remove the F/PUMP fuse from the engine room No. 2 junction block.
   2. Measure the resistance of the fuse.
      Fig 2: Identifying F/Pump Fuse From Engine Room Junction Block

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance: 

      Below 1 Ω 

   NG : REPLACE FUSE 

   OK : GO TO NEXT STEP. 

5. INSPECT INTEGRATION RELAY (Marking EFI NO. 2) 
   1. Remove the integration relay from the engine room No. 2 junction block.
   2. Measure the resistance of the EFI NO. 2 relay.
      Fig 3: Identifying Integration Relay At Engine Room Junction Block

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance 

      TESTER CONNECTION AND SPECIFIED CONDITION CHART
      
      

      Terminal Connections	Specified Condition
      2B-8 - 2C-1	10 kΩ or higher
      2B-8 - 2C-1	Below 1 Ω (when battery voltage is applied to terminals 2A-8 and 2B-3)

   NG : REPLACE INTEGRATION RELAY 

   OK : GO TO NEXT STEP. 

6. INSPECT INTEGRATION RELAY (Marking C/OPN) 
   1. Remove the integration relay from the engine room No. 2 junction block.
   2. Inspect the C/OPN relay.
      Fig 4: Identifying Integration Relay At Engine Room Junction Block

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance 

      TESTER CONNECTION AND SPECIFIED CONDITION CHART
      
      

      Terminal Connections	Specified Condition
      2B-8 - 2C-1	10 kΩ or higher
      2B-8 - 2C-1	Below 1 Ω (when battery voltage is applied to terminals 2B-7 and 2C-1)

   NG : REPLACE INTEGRATION RELAY 

   OK : GO TO NEXT STEP. 

7. CHECK ECM (FC VOLTAGE) 
   1. Turn the engine switch on (IG).
   2. Measure the voltage of the ECM connector.
      Fig 5: Measuring Voltage Of ECM Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard voltage 

      TESTER CONNECTION AND SPECIFIED CONDITION CHART
      
      

      Tester Connection	Specified Condition
      A6-14 (FC) - E7-7 (E1)	9 to 14 V

   NG : REPLACE ECM 

   OK : REPAIR OR REPLACE HARNESS AND CONNECTOR (ECM - C/OPN RELAY) 

8. INSPECT RELAY (Marking: F/PMP) 
   1. Remove the F/PMP relay from the engine room No. 2 relay block.
   2. Measure the resistance of the relay.
      Fig 6: Identifying F/PMP Relay From Engine Room Relay Block

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard resistance 

      TESTER CONNECTION AND SPECIFIED CONDITION CHART
      
      

      Tester Connection	Specified Condition
      3 - 4	Below 1 Ω
      3 - 4	10 kΩ or more (when battery voltage is applied to terminals 1 and 2)

   NG : REPLACE RELAY 

   OK : GO TO NEXT STEP. 

9. INSPECT FUEL PUMP 
   1. Check the resistance of the fuel pump.
      1. Measure the resistance between terminals 4 and 5.

         Standard resistance: 

         0.2 to 3.0 Ω at 20°C (68°F) 

   2. Check operation of the fuel pump.
      1. Apply battery voltage to both terminals. Check that the pump operates.
         Fig 7: Measuring Resistance Between Terminals 4 And 5

         Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002