Radiator and A/C Condenser Fan Low Speed Circuit Troubleshooting

NOTE: Do not use this troubleshooting procedure if the A/C compressor is inoperative. Refer to the symptom troubleshooting index. Before performing symptom troubleshooting, check for powertrain DTCs. Check the No. 9 (20 A) fuse in the under-hood fuse/relay box, and the No. 30 (7.5 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.■
Remove the A/C condenser fan relay from the under-hood fuse/relay box, and test it. Is the relay OK?
YES | - | Go to Step 3 .
NO | - | Replace the A/C condenser fan relay .■
Measure the voltage between the No. 1 terminal of the A/C condenser fan relay 4P socket and body ground. Is there battery voltage?
YES | - | Go to Step 4 .
NO | - | Replace the under-hood fuse/relay box.■

Connect the No. 1 and No. 2 terminals of the A/C condenser fan relay 4P socket with a jumper wire. Does the A/C condenser fan run?
YES | - | Go to Step 5 .
NO | - | Go to Step 20 .
Disconnect the jumper wire. Turn the ignition switch ON (II). |

Measure the voltage between the No. 3 terminal of the A/C condenser fan relay 4P socket and body ground. Is there battery voltage?
YES | - | Go to Step 8 .
NO | - | Repair open in the wire between the No. 30 fuse in the under-dash fuse/relay box and the A/C condenser fan relay.■
Turn the ignition switch OFF. Reinstall the A/C condenser fan relay. Remove A/C diode A from the left side (LHD) or the right side (RHD) of the dashboard. |

Check for current flow in both directions between the No. 1 and No. 2 terminals of A/C diode A. Is there current flow in only one direction?
YES | - | Go to Step 12 .
NO | - | Replace A/C diode A.■
Make sure the engine coolant temperature is below 93 °C (199 °F). Turn the ignition switch ON (II). |

Measure the voltage between the No. 2 terminal of A/C diode A 2P connector and body ground. Is there battery voltage?
YES | - | Go to Step 15 .
NO | - | Repair open in the wire between the A/C condenser fan relay and A/C diode A.■
Turn the ignition switch OFF. Reinstall A/C diode A. Disconnect climate control unit connector B (16P). Turn the ignition switch ON (II). |

Measure the voltage between the No. 13 terminal of climate control unit connector B (16P) and body ground. Is there battery voltage?
YES | - | Check for loose wires or poor connections at climate control unit B (16P) and at A/C diode A 2P connector. If the connections are good, substitute a known-good climate control unit, and recheck. If the symptom/indication goes away, replace the original climate control unit .■
NO | - | Repair open in the wire between A/C diode A and the climate control unit.■
Disconnect the jumper wire. Reinstall the A/C condenser fan relay. Disconnect the A/C condenser fan 2P connector. Turn the ignition switch ON (II), then turn the A/C and fan switches ON. |

Measure the voltage between the No. 2 terminal of the A/C condenser fan 2P connector and body ground. Is there battery voltage?
YES | - | Go to Step 25 .
NO | - | Replace open in the wire between the A/C condenser fan relay and the A/C condenser fan.■
Turn the A/C and fan switches OFF, then turn the ignition switch OFF. Reconnect the A/C condenser fan 2P connector. |

Connect the No. 1 terminal of the A/C condenser fan 2P connector to body ground with jumper wire. Turn the ignition switch ON (II), then turn the A/C and fan switches ON. Does the A/C condenser fan run?
YES | - | Go to Step 29 .
NO | - | Replace the A/C condenser fan motor.■
Turn the A/C and fan switches OFF, then turn the ignition switch OFF. Disconnect the jumper wire. Remove the fan control relay from the multi-relay box, and test it. Is the relay OK?
YES | - | Go to Step 32 .
NO | - | Replace the fan control relay.■
Turn the ignition switch ON (II), then turn the A/C and fan switches ON. |

Measure the voltage between the No. 1 terminal of the fan control relay 5P socket and body ground. Is there battery voltage?
YES | - | Go to Step 34 .
NO | - | Repair open in the wire between the A/C condenser fan and the fan control relay.■
Turn the A/C and fan switches OFF, then turn the ignition switch OFF. Disconnect the radiator fan 2P connector. |

Check for continuity between the No. 4 terminal of the fan control relay 5P socket and the No. 2 terminal of the radiator fan 2P connector. Is there continuity?
YES | - | Go to Step 37 .
NO | - | Repair open in the wire between the fan control relay and the radiator fan.■

Check for continuity between the No. 1 terminal of the radiator fan 2P 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 and body ground. If the wire is OK, check for poor ground at G301.■