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Overheating


jetfxrf16

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HELP!!-Neither of my cooling fans are working now. I found a cooling fan module from a junkyard and replaced it (twice)...and no fix. I replaced the electronic coolant temperature sensor (ECT) and it has not helped. I am at my wits end. The only thing that happens is when the vehicle is being driven the pusher fan will operate and not allow the car to overheat. The puller fan does not operate at all and if you turn the A/C on, the A/C compressor will shut off and give me an A/C overheat message. Moral of that story is do not turn on the A/C, but I have to get this fixed because I am in Phoenix, AZ and it is going to get HOTTTT. Please help with any other ideas.

Jetfxr

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Are you sure you replaced the correct module? Its a pretty chunky block mounted behind the drivers side headlight. They go bad all the time.

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Check to see what else is on the cooling fan circuit and see if those items are working. It may be different in your year but I had a fusible link burn out in my 91 Seville, and it took out the cooling fans, horn, AC clutch. Maybe there is a fusible link exclusively for the cooling fans in your year that burned out. Have you tried to see if the fans are operational by direct wiring them and see if they run, one of mine was badly burned up and you could smell that the armature was burned out. Its possible that both of your fans are defective and the controls are working and unable to turn the fans on as they are bad (bearings, brushes, armature, etc)... I have my fans direct wired to the battery temporarily.

If you determine that the only thing not running is your fans you could direct wire them and put a switch in the cockpit or wire them to the key power ON.... Mike

Early on sailors navigated by the stars at night and the North star became the symbol for finding ones way home. Once you know where the Northstar is you can point your ship in the right direction to get home. So the star became a symbol for finding ones way home or more symbolically even finding ones path in life.

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Its been a while since I replaced my module and I think there are two types and there is a way to tell them apart. Look over your original part and compare it with the replacement part. There is a tsb out on how to troubleshoot the fans If I remember it was not to hard. I dont throw anything away that has to do with repairing cars BUT OF COURSE I cant find the bulletin or the procedure. Dont despair the answer is there Its just a matter of finding it. Ill keep looking for my paperwork good luck. Mike

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Yes, I am sure I replaced the correct module. I matched up the numbers on my module with the new one I got. The car runs fine sometimes. The cooling fan on the forward portion of the radiator works fine when the car is being driven, but the fan on the aft side of the radiator never works and the A/C overheats. I will try to direct jumper them.

Mike - You may send the TSB directly to my personal email.

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How about checking the maxifuses? They are 50amp jobbies that are under the fuse cover in the engine compartment.

I had a problem where one of my fan motors seized up and blew the maxifuse, the little fuses where ok, just the maxifuse was blown, and it caused the same symptoms as yours.

John

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No the maxifuse is just that 50amp fuses that controls the power to the fan modules.

2 fuses, 3 relays.

Fuses-

maxi fuse 3 50 amp

fuse D3 10 amp

Relays-

cooling fan relay #1- LH side of engine. behind washer fluid tub

on wheelhouse

cooling fan relay #2- same as above

cooling fan relay #3- same as above

The PCM controls the fans. You may have lost the driver in the

PCM. There are 2 drivers. One for low speed and another for high

speed control. A new PCM is the only fix if the drivers are bad.

You can command the cooling fans on with the onboard

diagnostics to test them....

Enter diagnostics by simultaneously pressing and holding

the 'off' and 'warmer' buttons for several seconds. You'll see

the display check and then any codes displayed. After the codes

(if any) then the DIC will show a message "PCM?" At this point

remember that the 'lo' button is no and the 'hi' is yes. Answer

yes to the PCM? prompt by pressing the 'hi' button. The display

will then show 'PCM DATA?' answer no by pressing lo. Then it

will prompt 'PCM INPUTS?' answer no. Then it will prompt 'PCM

OUTPUTS?' answer no. Then it will prompt 'PCM OVERRIDES?'

answer yes with the hi button. Now scroll thru the PCM override

functions with the lo or hi button until you find PS08 which is

the cooling fan relay. Pressing the 'cooler' button will turn

the fans on low speed with the low speed fan relay. Pressing

the 'warmer' button will turn the fans on high speed with the

high speed fan relay. To exit press 'off' repeatedly or just

turn the key off.

Cooling fan 1,2 & 3 relay locations LH side of engine compartment behind windshield washer reservior.

Maxifuse location LH side of engine compartment on wheelhouse

If you send me your email address I will e,ail you the illustrations from the service manual. I was going to post them here, but could not get them fit the 64kb maximum limit.

John

jbuckley@sc.rr.com

John

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