Fuel Pump Control Circuit: Procedure

1. Connect Techstream to the DLC3.
2. Turn the ignition switch to ON and turn the Techstream on.
3. Select the following menu items: Powertrain / Engine / Active Test / Control the Fuel Pump/Speed.
4. Check whether the fuel pump operation sound occurs when performing the Active Test on the Techstream.

   OK

   Fuel pump operating sound occurs.

NG → See step   3 

OK → See step   2 

1. Check the ECM power source circuit. Refer to ECM Power Source Circuit .

NG → REPAIR OR REPLACE ECM POWER SOURCE CIRCUIT 

OK: Go to next step 

1. Inspect the C/OPN relay. Refer to INSPECTION .

NG → REPLACE ENGINE ROOM JUNCTION BLOCK 

OK: Go to next step 

1. Disconnect the ECM connectors.
   Fig 1: Identifying ECM Connectors

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Turn the ignition switch to ON.
3. Measure the voltage between the terminals of the ECM connectors.

   Standard voltage

   Tester Connection	Switch Condition	Specified Condition
   A55-7 (FC) - B50-81 (E1)	Ignition switch ON	11 to 14 V

4. Reconnect the ECM connectors.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - BATTERY) 

OK: Go to next step 

1. Inspect the fuel pump. Refer to INSPECTION .

NG → See step   9 

OK: Go to next step 

1. Check the harness and the connectors between the engine room relay block and the fuel pump.
   1. Disconnect the engine room junction block connector.
   2. Disconnect the fuel pump connector.
   3. Measure the resistance.

      Standard resistance (Check for open)

      Tester Connection	Condition	Specified Condition
      1D-3 - K7-4 (Fuel pump)	Always	Below 1 Ω

      Standard resistance (Check for short)

      Tester Connection	Condition	Specified Condition
      1D-3 or K7-4 (Fuel pump) - Body ground	Always	10 kΩ or higher

2. Check the harness and the connectors between the fuel pump and body ground.
   1. Disconnect the fuel pump connector.
   2. Measure the resistance.

      Standard resistance (Check for open)

      Tester Connection	Condition	Specified Condition
      K7-5 (Fuel pump) - Body ground	Always	Below 1 Ω

3. Reconnect the engine room junction block connector.
4. Reconnect the fuel pump connector.

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK → See step   8