Radiator Fan Circuit Troubleshooting
Radiator Fan Circuit Troubleshooting'00 - 05 models
1. Check the No. 57 (20 A), No. 41 (100 A), and No. 42 (40 A) fuses in the main under-hood fuse/relay box, and the No. 20 (7.5 A) fuse in the under-dash fuse/relay box.
Are the fuses OK?
YES - Reinstall the fuse, then go to step 2.
NO - Replace the fuse(s) and recheck.
2. Remove the radiator fan relay from the main 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 the radiator fan relay 4P socket terminal No. 1 and body ground.
Is there battery voltage?
YES - Go to step 4.
NO - Replace the main under-hood fuse/relay box.
4. Connect the 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, and turn the ignition switch to ON (II). Check for voltage between the radiator fan relay 4P socket terminal No. 3 and body ground.
Is there battery voltage?
YES - Go to step 9.
NO - Repair open in the wire between the main under-hood fuse/relay box and under-dash fuse/relay box.
6. Disconnect the radiator fan motor 2P connector.
7. Check for continuity between the radiator fan relay 4P socket terminal No. 2 and the radiator fan motor 2P connector terminal No. 2.
Is there continuity?
YES - Go to step 8.
NO - Repair open in the wire between the main under-hood fuse/relay box and the radiator fan motor 2P connector terminal No. 2.
8. Check for continuity between the radiator fan motor 2P connector terminal No. 1 and body ground.
Is there continuity?
YES - Replace the radiator fan motor.
NO - Repair 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. Reinstall the radiator fan relay.
10. Disconnect the radiator fan switch 2P connector.
11. Turn the ignition switch to LOCK (0). Connect the radiator fan switch 2P connector terminals No. 1 and No. 2 with a jumper wire, then turn the ignition switch to ON (II).
Does the radiator fan run?
YES - Replace the radiator fan switch.
NO - Go to step 12.
12. Turn the ignition switch to LOCK (0). Remove the jumper wire, then turn the ignition switch to ON (II). Measure the voltage between the radiator fan switch 2P connector terminal No. 2 and body ground.
Is there battery voltage?
YES - Repair 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 G301.
NO - Repair open in the wire between the radiator fan switch 2P connector terminal No. 2 and the main under-hood fuse/relay box.
'06 - 08 models
1. Check for the PGM-FI DTCs.
Is DTC P2183, P2184, and/or P2185 indicated?
YES - Do the appropriate troubleshooting, then recheck.
NO - Go to step 2.
2. '06 - 07 models: Check the No. 57 (20 A), No. 41 (100 A), and No. 42 (40 A) fuses in the main under-hood fuse/relay box, and the No. 20 (7.5 A) fuse in the under-dash fuse/relay box.
3. '08 model: Check the No. 57 (30 A), No. 41 (100 A), and No. 42 (40 A) fuses in the main under-hood fuse/relay box, and the No. 20 (7-5 A) fuse in the under-dash fuse/relay box.
Are the fuses OK?
YES - Reinstall the fuse, then go to step 4.
NO - Replace the fuse(s) and recheck.
4. Remove the radiator fan relay from the main under hood fuse/relay box, and test it.
Is the relay OK?
YES - Go to step 5.
NO - Replace the radiator fan relay.
5. Measure the voltage between the radiator fan relay 4P socket terminal No. 1 and body ground.
Is there battery voltage?
YES - Go to step 6.
NO - Replace the main under-hood fuse/relay box.
6. Connect the radiator fan relay 4P socket terminals No. 1 and No. 2 with a jumper wire.
Does the radiator fan run?
YES - Go to step 7.
NO - Go to step 8.
7. Disconnect the jumper, and turn the ignition switch to ON (II). Check for voltage between the radiator fan relay 4P socket terminal No. 3 and body ground.
Is there battery voltage?
YES - Go to step 11.
NO - Repair open in the wire between the main under-hood fuse/relay box and under-dash fuse/relay box.
8. Disconnect the radiator fan motor 2P connector.
9. Check for continuity between the radiator fan relay 4P terminal No. 2 and the radiator fan motor 2P connector terminal No. 2.
Is there continuity?
YES - Go to step 10.
NO - Repair open in the wire between the main under-hood fuse/relay box and the radiator fan motor 2P connector terminal No. 2.
10. Check for continuity between the radiator fan motor 2P connector terminal No. 1 and body ground.
Is there continuity?
YES - Replace the radiator fan motor.
NO - Repair 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.
11. Check for continuity between the radiator fan relay 4P socket terminal No. 4 and the engine control module (ECM) connector terminal E12.
Is there continuity?
YES - Update the ECM if it does not have the latest software, or substitute a known good ECM, then recheck it. If the symptom/indication goes away with a known-good ECM, replace the original ECM.
NO - Repair open in the wire between the ECM connector terminal E12 and the main under-hood fuse/relay box.