Main Relay (Computer/Fuel System): Testing and Inspection

CAUTION: When applying battery voltage directly to the Control Relay, verify connections are to the correct terminals. Otherwise, the Control Relay will be damaged.

Control Relay Location:

1. Remove the glove compartment and the cover under the glove compartment.
2. Disconnect the Control Relay electrical connector, and remove the relay.

Testing The Operation Of The Control Relay:

3. Connect the positive lead of a 12 volt power supply to terminal # 10 of the relay.
4. While connecting and disconnecting the voltage supply negative terminal to and from terminal # 8 of the relay, measure the voltage at terminals # 4 and # 5 of the relay.
^ While voltage is being supplied, 12 volts should be read at terminals # 4 and # 5.
^ When voltage is discontinued, voltage should NOT be read at either terminal # 4 or # 5.

Testing The Control Relay:

5. Connect the power supply negative lead to terminal # 6 of the Control Relay.
While connecting and disconnecting the power supply positive lead to terminal # 9, check for continuity between terminals # 2 and # 3.
^ While the positive lead is connected, there should be continuity between the terminals.
^ While the positive lead is disconnected, there should NOT be continuity between the terminals.

Control Relay Test:

6. Connect the power supply positive lead to terminal # 3 of the Control Relay.
While connecting and disconnecting the power supply negative lead to terminal # 7, check for and measure the voltage at terminal # 2 of the Control Relay.

^ While the negative lead is connected, 12 volts should be read on the voltmeter at terminal # 2
^ While the negative lead is disconnected, voltage should NOT (0 volts) be read on the voltmeter at terminal # 2.

If any of the above tests deviates from the indicated results, replace the Control Relay.