Radiator Fan High Speed Circuit Troubleshooting

Radiator Fan High Speed Circuit Troubleshooting
1. Remove the radiator fan relay from the under-hood fuse/relay box and test it.
Is the relay OK?
YES-Go to step 2.
NO-Replace the radiator fan relay.
2. Turn the ignition switch ON (II).





3. Measure the voltage between radiator fan relay 4P socket terminal No. 1 and body ground.
Is there battery voltage?
YES-Go to step 4.
NO-Check fuse No. 11 (30 A) in the under-hood fuse/relay box. If OK, replace the under-hood fuse/ relay box.





4. Connect radiator fan relay 4P socket terminals No. 1 and No. 2 with a jumper wire.
Does the radiator fan run at high speed?
YES-Go to step 5.
NO-Repair an open in the wire between radiator fan relay 4P socket terminal No. 2 and radiator fan motor 2P connector terminal No. 2.





5. Measure voltage between radiator fan relay 4P socket terminal No. 3 and body ground.
Is there battery voltage?
YES-Repair an open in the wire between radiator fan relay 4P socket terminal No. 4 and the engine control module (ECM)/powertrain control module (PCM).
NO-Repair an open in the wire between radiator fan relay 4P socket terminal No. 3 and the underdash fuse/relay box.