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

Main And Fuel Pump Relay Circuit:

Main And Fuel Pump Relay Location:

- Disconnect negative cable at battery.
- Remove main relay from ECM after disconnecting its connector.

Checking Relay Resistance:

- Check resistance between each two terminals.
TERMINALS RESISTANCE
A & B oo (infinity)
C & D 56-84 ohms
- If check results are as specified, proceed to next operation check. If not, replace.

Checking Relay Operation:

- Check that there is continuity between terminals "A" and "B" when battery is connected to terminals "C" and "D".
- If found defective, replace.