something odd is happening for the past few days. sometimes after the car has been driven, and the engine gets shut off, the fan stays on. thought this was odd, so we pulled the fan relay and the fan shuts off, plug it back in, the fan turns back on. so we pulled the relay and the negative cable on the battery and left it overnight. the fan stopped running when i plugged everything back in but after a long drive upon shutting off the engine, the fan runs.

my coolant is fine, just did a flush about a month ago.

thermostat?

PCM?

 

Some year after 99,not sure exactly what year, but the fan would come on after the engine was shut off from a trip to cool the engine.

 

fan temp sensor failure- located lower pass side corner of radiator
very common prob -
when it goes the fan will run for 15 minutes after shutdown- or not run at all~

make sure the system is burped

 

a few minutes of fan is perfectly normal as the temp rise when engine shuts down,
fan comes on to compensate for loss of airflow thru rad

my water cooled 2 wheel Honda does the same thing- ignition off after ride- fan on for a minute by itself

 

My buddy has an 01 CL-S and his fan would come on after he shut the engine off, but my 99 doesn't do that.

 

for assclown

and it will only do it depending on what temp the engine is when you shut off the car and such, so it is temperature based, let alone with the higher ambient temps, can't really complain

 

and piggy, my brothers old 92 accord use to turn on the fan after shutting off the car, but my 94 accord i don't ever remember it doing it though

but anyways to tell you the truth, the fan control module did not change much from all those years, just some seem to be more sensitive then others though, so easier for it to turn on the fans after shutting off the engine

 

all that matters is what the TL does~

Mine-01- runs for a minute or 2 after shutdown- and not based on extreme hot weather.
the engine is normal just below half /operating temp-
When you stop the flow of coolant the rad inner temp rises-
temp sensor in rad picks that up and turns fan on to help

when they fail usually it runs for a long time- enough to cause concern,,,
replace that and all should be well

If not- then I am happy to diagnose again,,at no additional charge!!
please move the modem closer to the car Sir

 

and don't forget to hook it up either

 

Yeah my 90 Accord used to do that, the fan came on after the car shut off.
So the fan control module is the same for all years ? My 99 TL never come on after i shut the car off, even long tip or over 90 degree days is there something wrong with mine ?
The coolant gauge always stay below middle though, i heard it come on once in a while when the engine running so i think it's okay.

 

i don't think exactly, but very similar though, and a long trip will more then likely not have it come on though, cause it will of had plenty of airflow through out the engine bay, and through the radiator, so it will not be too heat soaked

and those 90 degree days, more likely it will, but try sitting in traffic first, so it can really get heat soaked first then shut the car off (and keep the hood fully shut too)

and anyways this is from alldata:
If the engine coolant temperature is more than 104 degrees C (219 degrees F ) when you turn the ignition switch to LOCK (0), the radiator fan control module will turn on the radiator fan and let it run for about 15 minutes .


and as said before everybody's sensors are not exactly the same, and some are probably just a couple of degree's lower then others, but then also what type of driving you do really matters if it will come on or not afterwards

 

sit in the driveway for 10 to 15 minutes at idle
You should hear the fan come on and off a couple of times

Ck the res bottle cap- inside it a rubber hose must be firmly attached or you get an air bubble which can fool the fan temp sensor and keep the temp guage good while there is a problem
Often the rubber hose falls off the cap- and into the coolant- Now the transfer system cant work at all--ooops- install hose and ck for tight fit
top off radiator (when fully cold) and res bottle to cold full mark

If you find that hose off the cap- burp the system per owner book

 

seems like everything is running fine, i even did a 90 mile trip from louisville to home and no problems. sometimes i just worry too much and i've never seen this happen before.

 

keep a watch on the time of the fan on when you stop- there will be a normal amount- a minute or 5 --
more than 15 minutes would be bad in anyones description of the sensor so far

 

i live in ny and my car has been doing the same thing as well every since the warm weather really started to kick in, the fan would stay on for at least 5 mins and somestimes as long as over 15 mins, but now the problem has evolved when after long drives, (over 20 mins) whenever im at a red light whether the ac is on or not the temp begins to rise on the car, so im thinking one of the fans isnt working properly and the engine is just staying cool from the driving air, also i was stopped in traffic for about 10 mins with the ac and the temp rose to almost over heating.....any inputs or thoughts on wht i cud check

 

start with coolant level in the res bottle, and cold radiator is full
How many miles? if over 105kmiles its ready for water pump, or there is slack in the belt from failing tensioner- the water pump turns slower = less cooling
Examine the belt and watch its movement as friend revs engine to 2000
tensioner should move to take up slack

Look inside the radiator for any clogging- it should be shiny clean metal, you can see the cutouts in the panels are clear of crud

Fans- the driver side should run on and off with temp - sitting 10 minutes it should run a minute and shut off for a few- turn on--back off, keeping the minor fluctuations in check. If it doesnt, the fan temp sensor is probably bad- very common, easy diy

The passenger side fan is directly ac controlled as its primary job- when the ac compressor is engaged that fan needs to run as long as compressor is engaged-
the click you hear as ac cycles is the engagement--watch it as friend turns ac on and off and fan operates with that switch

overheat -dont let it happen or else $$$$ to replace heads-head gaskets
turn AC OFF when sitting now that you know-

anything above half on the temp guage is too hot for the TL !!! should run 1-2 clicks below half.

cars that get hot fast when sitting often have clogged radiator, or possible thermostat failing --even worn hoses that are soft to the squeeze when cold- can collapse and no flow of coolant
Most likey would be water pump/rad based on my own past car problems

With the engine at normal temp, feel the upper and lower rad hoses- should be a good differance between them if rad and thermostat is working

 

thanks for the advice i checked my coolant level, and the coolant resevoir is empty but my radiator is full. also no leaks that i can find, i bought the car a year ago i have to admit ever since i bought ive never checked the coolant level since i never had a problem, and i do have 121k on it now, so im hoping its nothing more than a bad thermostat or on extreme side a bad water pump/ and or bad belt.....illl keep my fingers crossed and you guys updated

 

was the rubber hose attached INSIDE the cap for the res bottle?
that likes to fall off and the system wont work then

121!!- Im guessing you got it cheap and it needs the 105 service with water pump replacement
get on that before you lose the engine

If the res bottle is empty and rad full- you are losing coolant in a hurry
borrow the pressure tester from parts store to find leak if needed.
w.p. has vent hole cast into it so when the rubber oring inside it fails- it drips coolant out that hole so you know- can be seen with a mechanics mirror or crawl under the car and look up

 

that's weird i have the same problem you guys know what can we do or what the problem might be??

 

Duh, its a turbo-timer!

 

Yesterday i notice the same thing. after the engine is turned off the radiator fan was still on. So is this just a simple radiator sensor? what is the part number for it?

 

i've had that before, sometimes it wouldn't even turn off... i would leave the car for like 20 mins and it still would be on! luckily aamco fixed it for me when i was rebuilding the tranny. i believe it was a fan temperature sensor like what 01tl4tl said

 

Its could be this super high temperatures we are having recently due to global warming.. My 99 just started to do this a week ago as well when the temps here in fla got to 103, and its not even summer yet. but everything is fine on the car so u should b good..

 

I have to disagree- global warming is not the cause of your fan running too long

its 100 here out west and no change in fan operation- thats the first clue- a change in fan operation

the fan temp sensor that causes the driver side fan to run a few minutes after shutdown should not run more than 15 minutes max
usually its ~2 minutes and the sudden temp spike that occurs at shutdown is resolved by the fan

when any problem with temp: STOP!! when cold radiator open it and fill to top if needed.
Ck the res bottle level at max cold level-
Inside the cap is a rubber hose- it MUST be firmly attached to the caps nipple or it falls into the coolant and no transfer can occur-
leads to air bubble in system and fooling of sensors and thermostat- thats bad

see if the driver side fan runs on and off when at idle- start the car and let sit in driveway 10-15 minutes (you can do the radiator air burp procedure in owner book to be certain- it calls for the fan to cycle several times)
Do that procedure with heater on high so heater core is open- its a good place to trap air

 

Was it the AC fan or the radiator fan? I bet it was the AC fan still running after the engine was turned off.

 

i'm still laughing at global warming haha. silly liberals.

"we didn't listen!!"

 

11749 on what do you base this?

the driver fan has the temp sensor for cooling

 

I have the same problem before.
The radiator motor fan is dying, it isnt spinning up to its maximum rpm and not cooling the radiator. That is why when you switch off the engine the driver side fan keeps running to cool the engine.
Open the hood let the engine run and look at the radiotor fan when it comes on, it is running weak. The motor will die some day and the tempreture gauge will raise.
I ordered the motor+shroud kit from rockauto.com but the shroud did not fit so I just replaced the motor using the old shroud and it fix the problem.

 

I heard of another fan wearout/failure problem on here recently

Another thing to ck- we should have a troubleshooting fan DIY with:
ck power wire at sensor and power at fan,
ck fan blade spins freely when off

 

Ok, i guess it was normal for the fan to run for a few mins after the car is shut off. My car has been sitting out in 108 degree weather for 5 hours and driving home in this heat didn't really help.

 

not to thread jack, but i do need some input

my TL-S has 172k, all services regularly done


recently when the car is left idling or i am in traffic moving alone slowly, i noticed that temp shoots up to half way or slightly higher. once moving it goes back down to normal. i hosed off the surface of the radiator yesterday and noticed that the problem is still there. both fans are kicking on.

last week for the first time in my three years of owning the car, the fans remained on for about 15mins after shut down

where is a good place to start? replace the thermostat or that sensor at the bottom of the radiator or both?

i didnt want to start another thread, so hopefully you guys can help me out.


thanks

Bryan

 

Hey same thing happened in my car it ended up being the relay< replaced it and went away.

 

Check the coolant level in the reservoir and radiator (when its cool).

When's the last time the coolant was flushed?

 

[quote=hANDYcaptd;12148512]Check the coolant level in the reservoir and radiator (when its cool).

When's the last time the coolant was flushed?[/quote]

a Ph level check is the best way of checking it normally, but yes you can base it somewhat on time though

then yes acidic coolant (below Ph 7) can induce voltage (very low, but still enough though) into sensors which cause them to give false readings

 

On my 99 the fans run whenever the key is on, even cold. I will have to look at the temp sensor. Cam.