Radiator Fan Relay Output: Testing
- Turn ignition off. Disconnect radiator fan relay connector. Radiator fan relay is located near driver's side frame rail. See Fig 1
. Connect a jumper wire between Orange/Red and Dark Blue/Dark Green wires at radiator fan relay harness connector. If one or both radiator fans is not operating, go to next step. If both radiator fans operate, no problem is indicated at this time. Test is complete.
- Disconnect jumper wire. Disconnect radiator fan connectors. Measure voltage between ground and Black/Dark Green wire at each radiator fan. If both resistance readings are less than 5 ohms, go to next step. If one or both resistance readings is 5 ohms or more, repair open in appropriate Black/Dark Green wire between radiator fan relay and ground connection. Ground connection is located near left headlight.
- Connect a jumper wire between Orange/Red and Dark Blue/Dark Green wires at radiator fan relay harness connector. Measure voltage between ground and Dark Blue/Dark Green wire at each radiator fan. If both voltage readings are more than 10 volts, replace radiator fans. If one or both voltage readings is 5 ohms or less, repair open in appropriate Dark Blue/Dark Green wire between radiator fan and radiator fan relay.
Courtesy of DAIMLERCHRYSLER CORPORATION