Radiator Fan High Speed Circuit Troubleshooting

NOTE: Before beginning this troubleshooting procedure, refer to the symptom troubleshooting index.

1. Check the No. 19 (30 A) fuse in the under-hood fuse/relay box.

Is the fuse OK?

YES | - | Go to Step 2 .
NO | - | Replace the fuse and recheck.■

1. Remove the radiator fan relay from the multi-fuse/relay box, and test it.

Is the relay OK?

YES | - | Go to Step 3 .
NO | - | Replace the radiator fan relay .■

1. 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 for an open in the wire between the under-hood fuse/relay box and radiator fan relay 4P socket terminal No. 1.

1. Connect radiator fan relay 4P socket terminal No. 1 and No. 2 with a jumper wire.

Does the radiator fan run?

YES | - | Go to Step 5 .
NO | - | Go to Step 6 .

1. Disconnect the jumper, and turn the ignition switch ON (II). Check for voltage between radiator fan relay 4P socket terminal No. 4 and body ground.

Is there battery voltage?

YES | - | Go to Step 9 .
NO | - | Check for an open in the wire between the under-hood fuse/relay box and radiator fan relay 4P socket terminal No. 4.■

1. Disconnect the radiator fan motor 2P connector.

1. Check for continuity between radiator fan relay 4P socket terminal No. 2 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 radiator fan relay 4P socket terminal No. 2 and radiator fan motor 2P connector terminal No. 2.■

1. 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 | - | Check for an 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 G301.■

1. Reinstall the radiator fan relay.

1. Disconnect the radiator fan switch (High) 2P connector.

1. Connect radiator fan switch (High) 2P connector terminal No. 1 and No. 2 with a jumper wire.

Does the radiator fan run?

YES | - | Replace the radiator fan switch (High). ■
NO | - | Go to Step 12 .

1. Remove the jumper wire, and measure the voltage between radiator fan switch (High) 2P connector terminal No. 2 and body ground.

Is there battery voltage?

YES | - | Check for an open in the wire between radiator fan switch (High) 2P connector terminal No. 1 and body ground. If the wire is OK, check for a poor ground at G302.■
NO | - | Repair open in the wire between radiator fan switch (High) 2P connector terminal No. 2 and the under-hood fuse/relay box.■