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

MFI Relay (ASD) And Fuel Pump Relay Check:

1. Remove the relay.
2. Check that there is continuity between (4) and (6) terminals.
- Standard value: 35-75 ohms
3. Use jumper leads to connect relay terminal No. 6 to the battery (+) terminal and terminal No. 4 to the battery (-) terminal.
- Check the continuity between relay terminals No.2 and No.8 while connecting and disconnecting the jumper lead at the battery (-) terminal.

Jumper lead Continuity between terminals No.2 and 8
- Connected = Continuity (0 ohms)
- Disconnected = No continuity (infinite resistance)

4. If there is a defect, replace the relay.