Radiator and A/C Condenser Fan Low Speed Circuit Troubleshooting

WARNING: This page is about a different car, the 2011 Honda Insight and 2010 Honda Insight. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

Do not use this troubleshooting procedure if the A/C compressor is inoperative. Refer to the SYMPTOM TROUBLESHOOTING INDEX .
Before doing symptom troubleshooting, check for powertrain DTCs (see GENERAL TROUBLESHOOTING INFORMATION ).

Check the No. 30 (30 A) fuse and the No. 10 (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 radiator fan relay from the auxiliary under-hood relay box, and test it (see POWER RELAY TEST ).
Is the relay OK?

YES -Go to step 3.

NO -Replace the radiator fan relay.
Connect the HDS to the DLC.
Turn the ignition switch to ON (II).
Turn the A/C and FAN to ON, on the climate control unit.
Check the FAN LOW CTRL in the PGM-FI Data List with the HDS.
Is the FAN LOW CTRL on?

YES -Go to step 7.

NO -Substitute a known-good PCM (see SUBSTITUTING THE PCM ), and retest. If the symptom/indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).
Measure the voltage between radiator fan relay 4P socket terminal No. 2 and body ground.

Fig 1: Measuring Voltage Between Radiator Fan Relay 4P Socket Terminal No. 2 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -Go to step 8.

NO -Repair an open in the wire between the No. 30 (30 A) fuse in the under-dash fuse/relay box and the radiator fan relay.
Connect radiator fan relay 4P socket terminals No. 1 and No. 2 with a jumper wire.

Fig 2: Connecting Radiator Fan Relay 4P Socket Terminals No. 1 And No. 2 With Jumper Wire
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Do the radiator and A/C condenser fans run?

YES -Go to step 9.

NO -Go to step 18.
Disconnect the jumper wire.
Turn the ignition switch to ON (II).
Measure the voltage between radiator fan relay 4P socket terminal No. 4 and body ground.

Fig 3: Measuring Voltage Between Radiator Fan Relay 4P Socket Terminal No. 4 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -Go to step 12.

NO -Repair an open in the wire between the No. 10 (7.5 A) fuse in the under-dash fuse/relay box, A/C DIODE A and the radiator fan relay.
Turn the ignition switch to OFF.
Reinstall the radiator fan relay.
Jump the SCS line with the HDS.
NOTE: This step must be done to protect the powertrain control module (PCM) from damage.
Disconnect PCM connector A (44P).
Connect PCM connector A (44P) terminal No. 4 to body ground with a jumper wire.

Fig 4: Connecting PCM Connector A (44P) Terminal 4 To Body Ground With Jumper Wire
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Turn the ignition switch to ON (II).
Do the radiator and A/C condenser fans run on low?

YES -Check for loose wires or poor connections at PCM connector A (44P). If the connections are good, substitute a known-good PCM, and recheck. If the symptom/indication goes away, replace the original PCM, then do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).

NO -Repair an open in the wire between the radiator fan relay and the PCM.
Disconnect the jumper wire.
Reinstall the radiator fan relay.
Disconnect the radiator fan 2P connector.
Turn the ignition switch to ON (II), then set the A/C button and fan control button ON.
Measure the voltage between radiator fan 2P connector terminal No. 2 and body ground.

Fig 5: Measuring Voltage Between Radiator Fan 2P Connector Terminal 2 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -Go to step 23.

NO -Repair an open in the wire between the radiator fan relay and the radiator fan.
Set the A/C button and fan control button OFF, then turn the ignition switch to OFF.
Test the radiator fan motor (see FAN MOTOR TEST ).
Is the motor OK?

YES -Go to step 25.

NO -NO - Replace the radiator fan motor (see FAN, FAN MOTOR, AND SHROUD REMOVAL AND INSTALLATION ).
Remove the fan control relay from the auxiliary under-hood fuse/relay box, and test it (see POWER RELAY TEST ).
Is the relay OK?

YES -Go to step 26.

NO -Replace the fan control relay.
Turn the ignition switch ON (II), then set the A/C button and fan control button ON.
Measure the voltage between fan control relay 5P socket terminal No. 1 and body ground.

Fig 6: Measuring Voltage Between Fan Control Relay 5P Socket Terminal 1 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -Go to step 28.

NO -Repair an open in the wire between the radiator fan and the fan control relay.
Set the A/C button and fan control button OFF, then turn the ignition switch to OFF.
Disconnect the A/C condenser fan 2P connector.
Check for continuity between fan control relay 5P socket terminal No. 4 and A/C condenser fan 2P connector terminal No. 2.

Fig 7: Checking Continuity Between Fan Control Relay 5P Socket And A/C Condenser Fan 2P Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Go to step 31.

NO -Repair an open in the wire between the fan control relay and the A/C condenser fan.
Check for continuity between A/C condenser fan 2P connector terminal No. 1 and body ground.

Fig 8: Checking Continuity Between A/C Condenser Fan 2P Connector Terminal No. 1 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Replace the A/C condenser fan motor (see FAN, FAN MOTOR, AND SHROUD REMOVAL AND INSTALLATION ).

NO -Check for an open in the wire between the A/C condenser fan and body ground. If the wire is OK, check for poor ground at G401.