Radiator Fan Circuit Troubleshooting

Radiator Fan Circuit Troubleshooting
1. Check the No. 57 (20 A) fuse in the under-hood fuse/relay box.
Is the fuse OK?
YES - Go to step 2.
NO - Replace the fuse and recheck.
2. Remove the radiator fan relay from the underhood fuse/relay box, and test it.
Is the relay OK ?
YES - Go to step 3.
NO - Replace the radiator fen relay.





3. Measure the voltage between the No. 1 terminal of the radiator fan relay 4P socket and body ground.
Is there battery voltage?
YES - Go to step 4.
NO - Replace the under-hood fuse/relay box.





4. Connect the No. 1 and No. 2 terminals of the radiator fan relay 4P socket with a jumper wire.
Does the radiator fan run?
YES - Go to step 9.
NO - Go to step 5.
5. Disconnect the jumper wire.
6. Disconnect the radiator fan connector.





7. Check for continuity between the No. 2 terminal of the radiator fan relay 4P socket and the No. 2 terminal of the radiator fan connector.
Is there continuity?
YES - Go to step 3.
NO - Repair open in the wire between the underhood fuse/relay box and the radiator fan.





8. Check for continuity between the No. 1 terminal of the radiator fan connector and body ground.
Is there continuity?
YES - Replace the radiator fan motor.
NO - Check for an open in the wire between the radiator fan connector and body ground. If the wire is OK, check for a poor ground at G201.
9. Disconnect the jumper wire, and turn the ignition switch on (II).





10. Measure the voltage between No. 3 terminal of the radiator fan relay 4P socket and body ground.
Is there battery voltage?
YES - Troubleshoot the radiator fan switch A circuit.
NO - Go to step 11.





11. Measure the voltage between the No. 1 terminal of the radiator fan control module and body ground.
Is there battery voltage?
YES - Repair open in the wire between the underhood fuse/relay box and the radiator fan control module.
NO - Perform the radiator fan control module input tests.