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

1. Remove the relay
2. Check the continuity between the MFI relay terminals. Continuity between terminals 2 & 4 should be approximately 70 ohms.





3. Use the jumper leads to connect relay terminal 4 to the battery (+) terminal and terminal 2 to the battery (-) terminal.
4. Check the continuity between relay terminals 1 & 3 while connecting and disconnecting the jumper lead at the battery (-) terminal.

Jumper lead Continuity between terminals 1 & 3
Connected Continuity (zero ohms)
Disconnected No continuity (infinite ohms)

5. If there is a defect, replace the MFI relay or the fuel pump relay.