My cooling fans arent coming on like they should. Is it a relay? And how do I determine which one?

Asked by Jul 17, 2014 at 03:14 PM about the 1996 Cadillac DeVille Sedan FWD

Question type: Maintenance & Repair

17 Answers

Could be. But check the wire from the sending unit that controls the fan. (I admit I stole that answer from dandyoun on a very similar question, and that was the problem) click to enlarge

24 people found this helpful.

I hot wired the fans to battery an they still want come on

17 people found this helpful.

My 1996 Deville had overheating issues. Bored hole through thermostat but then found out there was a small belt located under a cover that had broken. No one knew it existed and we found it by accident. I believe they said it was on the water pump. Small item but car runs well now and has no overheating issues. However, the ac/heating fan does not come on.... haven't fixed it yet as I keep getting if this and if that answers. Saw a video where tampering with the buttons on AC/heating could cause this too happen... actually, people pushing all those related buttons in the wrong sequence can cause this issue according to that video. Will get around to fixing it someday.

6 people found this helpful.

Under what cover? Can you pick it out from this? click for full screen

7 people found this helpful.

This is a different kind of pump. Not saying bad, just different

4 people found this helpful.

I went off topic for the relay location. I can't find the image as in the owners manual, can't copy and paste from a pdf. But Download and see chapter 6 Page 58 -

4 people found this helpful.

I havd a 2000 Cadillac seville That fans will not turn on and the car runs very hot at time but it stays at 12:00 then moves up slowly when stoped in traffic once i start moving my temp moves back to 12:00 idk what to do n i need my car thanks

36 people found this helpful.

Ok here's what's going on. You have a fault code in your acm system that's what controls the auto climate, the a/c compressor and the engine cooling fans. First thing to do is turn the key to run. Press and hold the auto/econ button while simultaneously pressing the red temperature heat button. The system will the start displaying all ecm pcm tcs acm etc codes including obd. At the end of the list of whatever codes are there it will prompt you to pcm clear codes? If you press up (fan blade speed increase

30 people found this helpful.

I haven't tried this method yet, but I was wondering what else if anything could be causing a/c to blow hot air and cooling fans not working?

2 people found this helpful.

Hey KidCadillac Was this issue ever fixed? Also Jermery will this work for a 2002 Deville as well?

3 people found this helpful.

what goes on when i turn my car on and my temp stays at 12:00 until i start moving about 20 feet my temp auto falls to the red and also theres a water leak under my passengers feet rest under the glove compartment

3 people found this helpful.

I have Cadilac Deville 2003 and in hot weather it has tendency to overheat. It has 2 powerful electric cooling fans. My question is - When should they turn on? They seems to be on ONLY when air-conditioning or defrost is on . The temperature gage never goes past the normal point, but in hot weather and some hill driving it starts boiling over. I know that these engines (NorthStar) have this problem. Could it help to turn on the cooling fans (by turning on defrost / air conditioning ) or would that make things even worse? I know that air-conditioning will produce even more heat, but the fans on may more than compensate for that ??

14 people found this helpful.

1996 cad sedan deville the left fan runs but the right fan do not run do that mean that the fan is bad

5 people found this helpful.

GuruT28H6 answered about a month ago 1996 cad sedan deville the left fan runs but the right fan do not run do that mean that the fan is bad No. It doesn't mean the fan is bad. You could have a short in the wiring harness, a bad relay, a bad fan electrical connector, or maybe, a bad fan. The easiest way to check the fan itself is to connect a 12 v. source directly to the fan's plugin connector. (I used a matching pigtail and a car battery.) If the fan runs then the problem lies elsewhere. Please note that there are YouTube videos covering this topic and pay attention to all objects that might intrude in the fan's operating space.

3 people found this helpful.

GuruT28H6 is right, could also be a bad ground, but a simpler way to check the fans is to just disconnect the coolant temp sensor harness,and your fans should run on high speed. I have been driving my 2000 STS like this for the last two months,l don't recommend this for long term because you have don't know what the coolant temp is ,car has not overheated since.bought a after market cooling fan temp sensor relay kit to put on.Especially since I had the head gaskets done on my 2000 STS 3 year's ago, and my 2001 DeVille 5years ago.


What does this do and where is it unplugged from?

1 people found this helpful.

Do any one know way I turn my ac on it blow my fans

1 people found this helpful.

Your Answer:


Looking for a Used DeVille in your area?

CarGurus has 792 nationwide DeVille listings starting at $2,750.


Cadillac DeVille Experts

  • #1
  • #2
  • #3
View All

Find great deals from top-rated dealersTM


Related Models For Sale

Used Cadillac Eldorado
212 listings starting at $2,995
Used Lincoln Town Car
26 Great Deals out of 1,050 listings starting at $995
Used Cadillac Seville
175 listings starting at $2,495
Used Chevrolet Impala
594 Great Deals out of 21,489 listings starting at $1,495
Used Lincoln Continental
56 Great Deals out of 2,658 listings starting at $15,000
Used Chevrolet Caprice
135 listings starting at $4,599

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use. Content will be removed if CarGurus becomes aware that it violates our policies.