Relays & Solenoids: Relays: Notes

A variety of relays are used and can be tested 2 different ways. The following relays can be tested using an ohmmeter and remotely supplied power and ground circuits:

• Electronic Control Module (ECM or ECCS) relay.
• Fuel pump relay.
• Main relay.
• Radiator/condenser (cooling) fan relay.
• Mixture heater relay.
• Neutral/inhibitor relay.

Safety relays can be tested using an ohmmeter, voltmeter and remote-ly supplied power and ground circuits. All testing procedures require proper identification of relay internals. See WIRING DIAGRAMS  at the end of this article.