Radiator Fan Circuit Troubleshooting

Radiator Fan Circuit Troubleshooting
1. Check the No. 4 (20 A) fuse in the under-hood fuse/relay box and the No. 14 (10 A) fuse in the under-dash fuse/relay box.
Are the fuses OK?
YES - Go to step 2.
NO - Replace the fuse(s) and recheck.
2. Remove the radiator fan relay from the under-hood fuse/relay box, and test it.
Is the relay OK?
YES - Go to step 3.
NO - Replace the radiator fan relay.





3. Measure the voltage between radiator fan relay 4P socket terminal No. 2 and body ground.
Is there battery voltage?
YES - Go to step 4.
NO - 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?
YES - Go to step 5.
NO - Go to step 6.





5. Disconnect the jumper wire, and turn the ignition switch ON (II). Check for voltage between radiator fan relay 4P socket terminal No. 3 and body ground.
Is there battery voltage?
YES - Go to step 9.
NO - Repair an open in the wire between the under-hood fuse/relay box and under-dash fuse/relay box.
6. Disconnect the radiator fan motor 2P connector.





7. Check for continuity between radiator fan relay 4P socket terminal No. 1 and radiator fan motor 2P connector terminal No. 2.
Is there continuity?
YES - Go to step 8.
NO - Repair an open in the wire between the under-hood fuse/relay box and radiator fan motor. 2P connector terminal No. 2.





8. Check for continuity between radiator fan motor 2P connector terminal No. 1 and body ground.
Is there continuity?
YES - Replace the radiator fan motor.
NO - Repair art open in the wire between radiator fan motor 2P connector terminal No. 1 and body ground. If the wire is OK, check for a poor ground at G201.
9. Turn the ignition switch OFF.
10. Reinstall the radiator fan relay.
11. Disconnect the radiator fan switch 2P connector.





12. Connect radiator fan switch 2P connector terminals No. 1 and No. 2 with a jumper wire.
Does the radiator fan run?
YES - Replace the radiator fan switch.
NO - Go to step 12.
13. Turn the ignition switch ON (II).





14. Remove the jumper wire, and measure the voltage between radiator fan switch connector terminal No. 2 and body ground.
Is there battery voltage?
YES - Repair an open in the wire between radiator fan switch 2P connector terminal No. 1 and body ground. If the wire is OK, check for a poor ground at G201.
NO - Repair an open in the wire between radiator fan switch terminal No. 2 and the under-hood fuse/relay box.