Good evening,

First off I am a shade tree mechanic at best. I do know how to use a volt meter but not so good with schematics. With that said I need some help and I am grateful for your help. My fans were not turning and my car ran hot while AC was running. I checked the fuse by the battery and I replaced the fans because my car has 127,000 miles on it but fans still do not run at any time. My AC compressor is engaging and disengaging at idle but works fine at speed. I don't have a lot of cash to put into the car so just wondering what I could or should check now after replacing the fans. Is there another fuse that controls the fans, relay or module. Any help would be appreciated. Thanks.

 

Did you replace the fans with new units? Have you tried connecting 12 volts straight to the motors to check they actually work?

The pair of fans work with 2 speed motors and come on at different speeds depending on whats required.
Usually the left fan comes on alone to cool the rad and the right one comes on with the a/c. There may be a few other scenarios but its something like that.

If not even the left fan comes on when needed you could easily overheat your engine. My first engine popped a hose because the fans didn't work. Afterwards it overheated again and that time the head gasket blew!

 

Yes new fans from rockauto. Neither fan runs when AC is on and from all I have read they should come on anytime the AC is on. I'm gonna drive it tomorrow a short drive to see if any fan comes on. Thanks.

 

Follow the troubleshooting steps in the CO & EC Sections of the FSM

http://forums.nicoclub.com/fsm-list-...g-t525067.html

http://www.nicoclub.com/service-manu.../Sedan/2008/CO

http://www.nicoclub.com/service-manu.../Sedan/2008/EC

NOTE:
Cooling fans are controlled by cooling fan control module. For details, refer to
EC-22, "
Component Parts Loca-
tion
"
.EC452

COOLING FAN
COOLING FAN
Description
INFOID:0000000001833222
COOLING FAN CONTROL MODULE
Cooling fan control module receives ON/OFF pulse duty
signal from IPDM E/R. Corresponding to this ON/OFF
pulse duty signal, cooling fan control module sends coo
ling fan motor operating voltage to cooling fan motor.
The revolution speed of cooling fan motor
is controlled by duty cycle of the voltage.
COOLING FAN MOTOR
Cooling fan motor receives cooling fan motor operating
voltage from cooling fan control module. The revolu-
tion speed of cooling fan motor is controlled by duty cycle of the voltage.
Component Function Check
INFOID:0000000001833223
1.
CHECK COOLING FAN FUNCTION
With CONSULT-III
1. Turn ignition switch ON.
2. Perform “FAN DUTY CONTROL” in
“ACTIVE TEST” mode
with CONSULT-III.
3. Make sure that cooling fan speed varies according to the percent.
Without CONSULT-III
1. Perform IPDM E/R auto active test and che
ck cooling fan motors operation, refer to
PCS-11, "
Diagnosis
Description
"
.
2. Make sure that cooling fan operates.
Is the inspection result normal?
YES
>> INSPECTION END
NO
>> Go to
EC-452, "
Diagnosis Procedure
"
.
Diagnosis Procedure
INFOID:0000000001833224
1.
CHECK COOLING FAN CONTROL MODULE POWER SUPPLY CIRCUIT


Component Inspection (Cooling Fan Relay)
INFOID:0000000001833226
1.
CHECK COOLING FAN RELAY
1. Turn ignition switch OFF.
2. Remove cooling fan relay.
3. Check the continuity between cooling fan relay terminals under
the following conditions.
Is the inspection result normal?
YES
>> INSPECTION END
NO
>> Replace cooling fan relay.
Cooling fan control module
Operation
Motor
Connector
Te r m i n a l
(+)
(–)
1E30145
Cooling fan operates.
2E30267
Terminals
Conditions
Conti

Good luck

Telcoman

 

I have checked the fuse in the fuse box behind the battery and all looks good. Fans still do not come on at all. How many relays control the fans and where are they physically located on the vehicle. I am not good with schematics, just need to know what to look for. Thanks, it's been cool so I haven't run the ac but it wanted to run a little hot in traffic on a warm day. I can probably replace the relays cheaper than I can have someone else check it for what's open in the circuit. Thanks for your help.

 

If you follow the instructions that telcoman posted with the FSM links you won't need to ask any more questions. Plain and simple, if you can't do that it's time to take it to a mechanic. We don't have any magic answers for you.

 

There is more than one way to skin a cat my friend. If I knew the physical location of all of the relays and replaced them one at a time I wouldn't have to read schematics or hire a mechanic if that solved my problem. I'm not saying that it would but it's worth a try at least. . That is all I asked for instead I get a bunch of slack from your post. You may not know what prodiamine and chlorothanil are used for but if you could run a sprayer I could help you get it applied or I could simply say that if you don't know what I know then then call a professional and pay through the nose.I was just asking for help. Not what I got!!! Have a nice day.

 

By the way, Thanks Telcoman for giving me the instructions to trace my problem. I will get a qualified person to trace it out for me and fix the issue. I am sure your time and knowledge is valuable and I do not want to seem ungrateful.

 

There are three cooling fan relays and they are controlled by your IPDM. Pull off the black cover behind the battery and if you have an 05+ it's the three relays in the middle. The top one is cooling fan relay 3, cooling fan relay 2, and cooling fan relay 1.

You want to test each relay by pulling it out of the module, applying power to the terminals on the relay that complete the circuit (should click), and then check for continuity on the other terminals.

I would also unplug the cooling fans from the wiring harness and supply voltage to see if they turn on. It uses the voltages from all three relays to either turn off, low, or high.

Off - All three relays off
Low - Relay 1 = On, Relay 2/3 = Off
High - Relay 1,2,3 = On

To get the motors to run at low speed manually, I think you want to put power +12v to either terminals 1 or 2 and -12V to either 3 or 4.
To get the motors to run at high speed manually, I think you want to put power +12v to both terminals 1/2 and -12V to both 3/4.

Motor 1 - Terminal 1 = LG Wire. Terminal 2 = L Wire, Terminal 3 = B Wire, Terminal 4 = Y Wire
Motor 2 - Terminal 1 = R Wire, Terminal 2 = L/W wire, Terminal 3 = B Wire, Terminal 4 = Y/R wire

If it's an IPDM failure you're looking at an expensive repair.

Check your coolant temperature sensor also.

 

Many apologies, reading my post again I was kind of an a-hole.

Good luck and let us know how it turns out.

 

No problem. I am grateful for all of the help. You can spend a fortune on any of the modern cars but you can save a bundle with just a few tips. I have found the people on this forum to be very sharp. I want to get my car fixed so I can sell it since I bought a new truck. I don't want to pass my problems on to someone else. All is good and again to all I say Thanks!!