Fuel Pump Relay: Testing and Inspection

Relay Terminal Identification:

FUEL PUMP RELAY TERMINAL IDENTIFICATION
The following is a list of the terminal numbers, with circuit codes, and color codes, and their function:

Circuit No. Terminal No. Color Code Description

A05 30 RED Has battery input voltage supplied through fusible link.

A61 87 ORG/BLK Connected to terminal 30 in the energized position, supplies output voltage to fuel pump, EGR/EVAP solenoid, and fuel injectors.

K5 86 VIO/WHT Connected to the ignition relay (terminal 30), which provides input voltage to the relay.

A62 85 ORG/GRN Connected to the ECU, and grounded by the ECU when distributor signal is present.

N/A 87A N/A Not used in these applications.

FUEL PUMP RELAY TEST
NOTE: The following test procedures assume that the ignition system is functioning, and that a good spark is evident at the plugs. If this not the case test the ignition system before proceeding with this test.
NOTE: The Fuel Pump relay operation may be tested with the use of the DRB II scanner or equivalent.
If no scanner is available proceed with the following test.

1. Using a digital voltmeter connect the negative lead to ground and the positive lead to the terminal 30 wire of the fuel pump relay connector.
^ If no voltage is present, check fusible links and supply voltage from the battery.
^ If battery voltage is present proceed to step 2.
2. Move the voltmeter positive lead to the terminal 87 wire of the fuel pump relay connector. Turn the ignition key to the START position and crank the engine.
^ If battery voltage is present during cranking, the fuel pump relay is functioning normally. Test fuel pump circuit for voltage and ground at fuel pump.
^ If no voltage is present at terminal 87 proceed to step 3.
3. Move the voltmeter positive lead to the terminal 86 wire of the fuel pump relay connector. Turn the ignition key to the RUN position. Battery voltage from the ignition relay (terminal 30) should be present.
^ If voltage is present proceed to step 4.
^ If no voltage is present there is either a bad connection or an open wire between terminal 30 of the ignition relay and terminal 86 of the fuel pump relay. Locate and repair bad connector or open in wire, and test operation.
4. Move voltmeter positive lead to terminal 85 of the fuel pump relay connector. Turn ignition key to START position, and crank engine, while observing voltage. Voltage should be present and drop to less than 1 volt within 2 seconds during cranking.
^ If voltage drops, and there is voltage at terminal 30 and no voltage at terminal 87 the relay is bad. Replace the fuel pump relay and check operation.
^ If voltage does not drop, proceed to step 5.
^ If no voltage is present, disconnect the fuel pump relay, and connect an ohmmeter between terminal 86 and terminal 85 of the fuel pump relay and check for continuity. If no continuity exists replace the fuel pump relay and test operation.
5. Disconnect the 35 way ECU, and 6 way diagnostic connectors and fuel pump relay. Connect an ohmmeter between terminal 85 of the fuel pump relay connector and the yellow wire at pin connector no. 3 of the ECU. Check for continuity.
^ If no continuity exists repair open in wire, reconnect ECU and fuel pump relay, and test operation.
^ If continuity exists, the problem is computer related.