Cooling Fan Stays On
 

So the cooling fan on the driver's side of my 2000 TL-P has started staying on after I turn off the engine. My car has never done this in the past. I did a search on here and found a thread, read it, and implemented the suggested fixes: i.e. coolant temp sensor, checking res for loose hose, all the simple stuff. Fan still stays on.

Someone mentioned a sensor on the bottom corner of the radiator, but mine doesn't seem to have a sensor there. I guess it varies by year?

Any ideas?

https://acurazine.com/forums/2g-tl-problems-fixes-117/fan-running-when-engine-not-778068/

mine still does it every now and then. i just let it do its thing.

Only the TL-S has the Radiator Fan Switch C sensor. My '00 is doing the same thing as yours for the first time this year; probably one of the other two sensors; my temp gauge is always spot-on though. One is easy to replace, the other requires some disassembly.

Only the J32A2 has that.

So you replaced the coolant temp sensor? It would be the radiator temp sensor that you should/would replace.

On the J32A1, there are only two switches that control the coolant fan: Switch A and Switch B (Switch C exists only on the J32A2).

The instrument panel temperature gauge gets its info from a completely different sensor, a thermistor called the Engine Coolant Temperature Sensor. It has absolutely nothing to do with controlling the fan.

Fan Switch A is easy to locate and replace. Switch B requires you to remove the upper covers and a bunch of other stuff.

Your best bet is to narrow it down first to which sensor. When the fan is running when the car is off, disconnect the electrical connector to Switch A. If the fan stops, Switch A had it turned on.

Check the thermostat. I had the same problem and the reason why the fans were on was because my thermostat wouldn't open all the way and my car would run hotter than normal.

Ok, so now my three options are:
1. radiator temp sensor (fattyms1), where is that?
2. radiator fan switch A (Severin)
3. thermostat (eleventure)

I am not the best electrical guy in the world, so excuse my ignorance. Let's say for example that the problem is the thermostat and I am going to try and test using Severin's method. Wouldn't unplugging the fan sensor A turn off the fan regardless of the problem (no current, no fan running)?

My thermostat is less than a year old. Does fan switch A run the driver's side fan and fan switch B run the passenger side fan?

Thank you for all of your input.

Personally, if it were the thermostat, you should see your car overheating on the temperature gauge; the temp gauge and fan controls are totally separate.
No, unplugging sensor A will not cause the fan to turn OFF if Sensor B has switched on. Either A, B or BOTH act as path to Ground.

I'm not trying to be insulting but my fan started running after I turned off the engine and someone here suggested I top off the antifreeze, I did and it hasn't run post engine turn off since. I felt pretty stupid but heck it worked. Good Luck.

Thanks again for the input. I'm always willing to listen to others and to learn...I just like to know all of the details. I did top off the antifreeze and I'm still having the problem. I guess I could just let it do it's thing and hope it doesn't wear out my battery. At least the car runs good and the engine stays cool. Never mind the occasional tranny slipping...

the rad and or res bottle low- how much?
A constant leak will cause a problem the fan is trying to overcome

So before I had made my original post I had topped off the res bottle. Upon actually following the proper procedure of how to fill both the res and radiator itself as outlined in the service manual...my problem has subsided.

Maybe a moderator can remove this post so that there is no record of my oversight and general incompetence.

naw- leave it up with your final fix was: to correctly fill and burp the system

What was the original cause- you replaced coolant?
something made the level go down!!

I was wondering about what caused the level to go down as well. I have not noticed any leaks on the ground and it has been a looooong time since I have done anything wtih the coolant.

ck the rad cap- has been popular failure this week..cheap to replace

run a pressure test on the rad system for leaks

found the leak today...all over the ground. as i was driving i heard a strange noise under the hood. i thought it was a squealing belt at first, but after i got to my destination my fan stayed on. i hadn't noticed a leak before, but now i've got coolant pouring out of the bottom center of my radiator, or at least that's where it is dripping from. i'm assuming the easiest thing to do would be to just replace the radiator? the only problem with that is that i'd hate to spend $100 on a new radiator and for the leak to be somewhere else. i guess things like this are to be expected when your car has 150k on it (1st transmission!!!).

remove rad if you can,, otherwise have it towed to a radiator shop

they can determine if its a seam leak or needs full replacement,
and get you a decent price on a replacement and install if needed

Thanks for all of the advice...hopefully the ol' junker will be back on the road soon!

it'll be a junker if the temp gets in the red~

Yep, that's why it's sitting in the driveway and not moving.

Slapped a new radiator in this afternoon and everything is cool. Old radiator was bulged and busted at the bottom center where the plastic and aluminum meet up. Maybe I can get a few bucks at the recycling center...

my cooling fan always comes on as well, only the driver side turns out. Would I need to replace the switch? any part # and diy's?

the driver fan has a temp sensor at the radiator bottem
It operates as needed for 1-2 minutes, usually when stopped in traffic-- thats normal use,,
AND it operates full time along with the pass fan- with ac ON

if driver fan doesnt come on ever OR runs for 5-10 minutes after shutdown,,
or you have temp guage movement when stable is normal..then its a sensor

pass fan is run by the AC being ON,,when the compressor cycles off when temp is reached,,the pass fan gets a rest too
compressor kicks back on- so does the fan
It takes a lot of air getting pulled thru both those radiators to stay cool in traffic

so its normal for the driver side fan to come on without the passenger side, and passenger side fan comes on only with ac?

IF the ac is OFF, the pass fan will not be running
the driver side fan will run on its own as needed, AND with the ac ON

BOTH fans must be ON with AC

IF driver fan runs more than 1-2 minutes at shutdown,,meaning 5-10 minutes running after engine shutdown,,its needs a fan temp sensor

Question, My girl friend drive my car(2001 CL-S) for the second time (was not in the car), she put the shifter in SS, and drove about 8 miles.. 5 miles of it was free way, not knowing she had to manually shift, so it was riding in around 6k rpm ok the freeway. She thought there was something wrong with it when she got home..... I checked it, everything seemed fine except the driver side fan ran for about 10 mins after shut off. I had the car for over a year now and never had that can kick in after shut off. Do anyone think this could cause a potential problem in the near future?

^^ Nope...


Fan ON after the car runs on a high RPM for too long is normal.. The ECU wants the Anti-freeze running at its optimal temperature and since you shut down the car there isn't any RAM air helping cool the A/F so what the ECU does? It creates vacuum with the FAN and makes the A/F reduce its temperature for some minutes with the car shut down.

Pretty normal on any modern car/moto/anything with engine..

What gear was selected.....?
 

:wish: Hey Dee Saelee, fan was just doing it's job. Should'nt be any problem.

:ugh: Did she say what gear position that the shifter was put into ?
Ya need to tell her to leave it in the regular drive position. She probably has watched ya manually shifting the SS .....and thought that she was doing the right thing, but got stuck. An instructional driving lesson may be in order for your girlfriend, with you in the car....ha, hah !!! :)

Thanks Skirmich,

She thought that the SS was D5 so it just shift into 2nd by itself, and no I'm not going to give her lessons. Cuz she is not going to touch my car again, lol

^ Wise man...

Wise man.....?
 

:tongue: Yeah, but Christmas is coming and ya may not get nothing from her.