A/C and cooling fan problem HELP
Thread Starter
Burning Brakes
Joined: Apr 2000
Posts: 935
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From: Melbourne Florida
A/C and cooling fan problem HELP
I noticed my A/C stopped working yesterday. Then when I was looking into it I realized the cooling fans are not spinning and I see in the manual says there connected. No cooling fans no A/C.
Any leads on what to look for ?
Is it possible the fan blades are broken from the motor, and are there replacement parts or must it replaced as a unit?
Thanks for the help guys/gals it gets got in Florida in a month or two.
Jeff
Any leads on what to look for ?
Is it possible the fan blades are broken from the motor, and are there replacement parts or must it replaced as a unit?
Thanks for the help guys/gals it gets got in Florida in a month or two.
Jeff
Melting Slicks
Joined: Dec 2004
Posts: 3,285
Likes: 52
From: Jacksonville, FL
St. Jude Donor '08 thru '26
On my 90 there are two fan relays on the left side of the radiator shroud. The helm book says when the A/C comp is engaged both should come on, also at a specific water temp the primary fan comes on and then at another higher set point the secondary fan comes on. The ECM provides a switched ground for the relays, that's how it turns on the fans.
I would think you could have the relays tested and you could probably discon the fan plugs and supply 12v + ground to test if the motors run.
Sorry I'm a new C4 owner & I don't know too much!
Tom
I would think you could have the relays tested and you could probably discon the fan plugs and supply 12v + ground to test if the motors run.
Sorry I'm a new C4 owner & I don't know too much!
Tom
Race Director
Joined: May 2005
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From: Middletown, DE
Do you have the electronic automatic CC? Does the LED indicator above the mode button you selected blink for a minute when you start the car? If so, there's a procedure you can go thru that self-diagnoses the problem. My AC stopped Sunday; same symptoms as you -- and I had the blinking LED. The Helms manual says push and hold the fan "up" and "down" arrows at the same time for 5 seconds. The LCD shows "-00". Then push "AUTO FAN" and the LCD shows a code from "00" to "10". If you get "09" like I did, it's just low Freon (although I suppose that does mean something is probably leaking). So, it goes to my trusted mechanic on Friday -- with any luck just a charge and perhaps a valve or seal (I'm no mechanic but I like having the manual so I'm a bit more knowledgable about things!)
Anyway, other codes mean something else mechanical or electronic is wrong -- and there's even more info you can get about different system parameters and circuits by following the recommended procedures. But, if you don't have the manual, at least try what I did and post the results here -- I bet you will get a ton of help quickly!
Good luck
Anyway, other codes mean something else mechanical or electronic is wrong -- and there's even more info you can get about different system parameters and circuits by following the recommended procedures. But, if you don't have the manual, at least try what I did and post the results here -- I bet you will get a ton of help quickly!
Good luck
Thread Starter
Burning Brakes
Joined: Apr 2000
Posts: 935
Likes: 0
From: Melbourne Florida
Electronic CC
blinking light is low freon for sure I had a friend with that mine is solid
that was why I was thinking the fan issue
I will try to hard wire to see if the fans are good, that is a good idea
then it is up to the sensors.
I have the shop manuals just always check here because everone is a wealth of knowledge
thanks for the input
blinking light is low freon for sure I had a friend with that mine is solid
that was why I was thinking the fan issue
I will try to hard wire to see if the fans are good, that is a good idea
then it is up to the sensors.
I have the shop manuals just always check here because everone is a wealth of knowledge
thanks for the input
Last edited by JazyJeff13; Apr 18, 2006 at 10:03 AM.
Race Director
Joined: Aug 2003
Posts: 13,421
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From: Lake Mary Florida
Originally Posted by JazyJeff13
Electronic CC
blinking light is low freon for sure I had a friend with that mine is solid
that was why I was thinking the fan issue
I will try to hard wire to see if the fans are good, that is a good idea
then it is up to the sensors.
I have the shop manuals just always check here because everone is a wealth of knowledge
thanks for the input
blinking light is low freon for sure I had a friend with that mine is solid
that was why I was thinking the fan issue
I will try to hard wire to see if the fans are good, that is a good idea
then it is up to the sensors.
I have the shop manuals just always check here because everone is a wealth of knowledge
thanks for the input
Even with the AC off, your fans will kick on at the max temp range which I believe will be 228 coolant for primary and 235 for the secondary. But I have to go back to the books to look and verify I'm remembering the values correctly. Either way the point is if you let it idle and come up to temp 228, the fan should kick on.
Race Director
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From: Lake Mary Florida
Originally Posted by JazyJeff13
I've got no cooling fans at all
I have to make sure I get that fixed first
Thanks for the high pressure switch idea
I have to make sure I get that fixed first
Thanks for the high pressure switch idea
How high have you let the coolant temp approach before determining there are no cooling fan operations?
You should have two relays on the driver's side of the radiator housing. Those are for the primary and secondary.
The reason I stated the above is to ascertain whether or not it is a total break down in communication from the ECM or just a relay. If it reaches the upper range and the secondary doesn't come on. Then its a different problem but if the secondary does come on then you could swap relay's I suppose to verify. Also both fans are powered from the 5am Fan fuse.
Thread Starter
Burning Brakes
Joined: Apr 2000
Posts: 935
Likes: 0
From: Melbourne Florida
I understand now, just figured when I put it on defrost it should have kicked both on
I did not let it get hot it hit 215 and i used the defrost and heat to cool it, I will give it a try.
where is the 5 amp fuse on the passenger side panel or under the hood?
I did not let it get hot it hit 215 and i used the defrost and heat to cool it, I will give it a try.
where is the 5 amp fuse on the passenger side panel or under the hood?
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Le Mans Master
Joined: Dec 2000
Posts: 7,839
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From: San Diego, Ca
Actually your looking for the low pressure switch - the high pressure (or simply pressure switch) on your year is a thermistor with a 3 wire reference from the PCM. Jumpering that switch will kill it as the PCM will sense extremely high pressure.
Jumpering the low pressure switch may or may not work. PCM monitors this switch for cycling or how fast the compressor is turning on and off. It also expects the voltage return from the pressure switch to rise when you turn the a/c on. Too much cycling and no voltage increase indicates a low charge condition, sets a trouble code and the PCM won't ground the compressor relay until memory is cleared from the Programmer. Try that first by disconnecting and reconnecting the battery. If the charge is low, it should work temporarily and then set the code which will be indicated by a flashing LED in the Display. 9 is low gas - there are other codes for other devices used by the system. A fault in any will shut it down.
Jumpering the low pressure switch may or may not work. PCM monitors this switch for cycling or how fast the compressor is turning on and off. It also expects the voltage return from the pressure switch to rise when you turn the a/c on. Too much cycling and no voltage increase indicates a low charge condition, sets a trouble code and the PCM won't ground the compressor relay until memory is cleared from the Programmer. Try that first by disconnecting and reconnecting the battery. If the charge is low, it should work temporarily and then set the code which will be indicated by a flashing LED in the Display. 9 is low gas - there are other codes for other devices used by the system. A fault in any will shut it down.
Race Director
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From: Lake Mary Florida
Originally Posted by SunCr
Actually your looking for the low pressure switch - the high pressure (or simply pressure switch) on your year is a thermistor with a 3 wire reference from the PCM.
I'm not even sure you have to start it up, by just jumpering and putting the ignition to On should cause the fan to kick on antisipating the AC pressure switch value.
Picture of switch to jump.
Last edited by Jet-Jock; Apr 19, 2006 at 09:40 AM.
Race Director
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From: Lake Mary Florida
You said you have the FSM's, if so you may wish to read up on modes of the diagnostics. I believe there is a mode page you can evoke which will cycle a particular relay. You hear the relay cycle and can verify it is working or not.
I said ECM before but on 94's I believe it is now called PCM. Either name, the point is PCM is controlling the ground signal to the relays which should always be hot minus the grounds.
I said ECM before but on 94's I believe it is now called PCM. Either name, the point is PCM is controlling the ground signal to the relays which should always be hot minus the grounds.
Race Director
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From: Lake Mary Florida
Originally Posted by JazyJeff13
I let it run up to 230 and nothing happened so both fans are out
Thread Starter
Burning Brakes
Joined: Apr 2000
Posts: 935
Likes: 0
From: Melbourne Florida
Originally Posted by Jet-Jock
Sorry mis-quoted but it should be a two wire switch I believe. I think I have a picture at home to reference if necessary.
I'm not even sure you have to start it up, by just jumpering and putting the ignition to On should cause the fan to kick on antisipating the AC pressure switch value.
Picture of switch to jump.
I'm not even sure you have to start it up, by just jumpering and putting the ignition to On should cause the fan to kick on antisipating the AC pressure switch value.
Picture of switch to jump.
I fianlly figured out the primary fan comes on at 228 F on the display so I can keep an eye on that in the future.
Jeff
Last edited by JazyJeff13; May 1, 2006 at 12:44 PM.