Checking the main injection relay
A. There must be a circuit between the terminals
B. Gap
1. The fuel system electrical circuit includes two relays - the EFI relay and the pump relay. The EFI relay is mounted in the relay block in the engine compartment, the pump relay is located under the front panel. First check for battery voltage on the main relay, and then on the fuel pump relay.
2. Disconnect the main relay from the connector, then turn on the ignition (do not start the engine) and check for voltage from the battery at the point where it is connected.
3. If there is voltage from the battery, then put the main relay back in place and check for voltage from the battery to the fuel pump relay.
4. If battery voltage is present on both relays, then check the relays themselves.
Main EFI relay
1. Use an ohmmeter to check for continuity between terminals 1 and 2 and 3 and 4.
2. Apply voltage from the battery to terminals 1 and 2. There should now be a closed circuit between terminals 3 and 4. If the test results differ, replace the relay.
Checking the fuel pump relay
Location of fuel pump relay on Toyota 4 Runner/ Hilux/ Surf
Checking the fuel pump relay
A. There should be a circuit between these terminals
B. Gap
1. Use an ohmmeter to check the integrity of the circuit between the contacts according to the diagram.
2. Apply voltage from the battery to terminals 1 and 2. There should now be a closed circuit between terminals 3 and 4. If the test results differ, replace the relay.