A/C Condenser Fan High Speed Circuit Troubleshooting
A/C Condenser Fan High Speed Circuit Troubleshooting
NOTE:
Do not use this troubleshooting procedure if the A/C compressor is inoperative. Refer to the symptom troubleshooting index.
If A/C refrigerant pressure is abnormal, the radiator fans are controlled based only on engine coolant temperature.
Before doing symptom troubleshooting, check for PGM-FI DTCs.
1.
Fuse check:

Fuse check
?1.
Check the following fuses.
Fuse
No. A2-10 (20 A)
Location
Under-hood fuse/relay box

Fuse
No. A8 (7.5 A)
Location
Under-hood fuse/relay box

Are the fuses OK?

     
YES
     
     
     
Go to step 2.
     
NO
     
     
     
Replace the fuse, and recheck. If the fuse blows again, repair a short in the No. A2-10 (20 A) fuse or the No. A8 (7.5 A) fuse circuit.?
2.
A/C condenser fan low speed operation check:

A/C condenser fan low speed operation check
?1.
Jump the SCS line with the HDS, and wait more than 1 minute.

NOTE: This step must be done to protect the PCM from damage.

?2.
Disconnect the following connector.
PCM connector A (51P)

?3.
Connect terminals A and B with a jumper wire.
Terminal A
PCM connector A (51P) No. 9
Terminal B
Body ground

?4.
Turn the vehicle to the ON mode.

Does the A/C condenser fan (and radiator fan) run on low?

     
YES
     
     
     
Go to step 3.
     
NO
     
     
     
3.
A/C condenser fan high speed operation check:

A/C condenser fan high speed operation check
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Connect terminals A and B with jumper wires.
Terminal A
PCM connector A (51P) No. 10
Terminal B
Body ground

Terminal A
PCM connector A (51P) No. 16
Terminal B
Body ground

?3.
Turn the vehicle to the ON mode.

Does the A/C condenser fan (and radiator fan) run on high?

     
YES
     
     
     
Update the PCM if it does not have the latest software, or substitute a known-good PCM, and recheck.?
     
NO
     
     
     
Go to step 4.
4.
A/C condenser fan relay check:

A/C condenser fan relay check
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Disconnect the jumper wires.

?3.
Reconnect PCM connector A (51P).

?4.
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 5.
     
NO
     
     
     
Replace the A/C condenser fan relay.?
5.
Open wire check (+B SUB FAN line):

Open wire check (+B SUB FAN line)
?1.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
A/C condenser fan relay: disconnected
Test point 1
A/C condenser fan relay 4P socket No. 1
Test point 2
Body ground


Is there battery voltage?

     
YES
     
     
     
The +B SUB FAN wire is OK. Go to step 6.
     
NO
     
     
     
Repair an open in the wire between the No. A2-10 (20 A) fuse and the A/C condenser fan relay in the under-hood fuse/relay box.?
6.
Open wire check (SUB FAN DIODE- line):

Open wire check (SUB FAN DIODE- line)
?1.
Turn the vehicle to the ON mode.

?2.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle ON mode
A/C condenser fan relay: disconnected
Test point 1
A/C condenser fan relay 4P socket No. 3
Test point 2
Body ground


Is there battery voltage?

     
YES
     
     
     
Repair an open in the wire between the A/C condenser fan relay and the PCM.?
     
NO
     
     
     
Repair an open in the wire between the No. A8 (7.5 A) fuse and the A/C condenser fan relay in the under-hood fuse/relay box.?