I first noticed the problem when I helped a friend jump start a car.

When my car is on, the temperature gauge usually idles slightly below the halfway mark between H and C.

The other day I was in parking lot with my car on, talking on my cell phone. The car was on, in park, with the AC off. After about 8-10 minutes, the temperature gauge started to move up toward hot so I turned off my car.

Today, I take it to my friends dad's shop and he checked it out for coolant leaks but didn't find any. We let the car idle but the temperature gauge didn't move. I pressed on the gas for a bit to rev the engine and finally after a minute or so the temperature gauge started to move toward hot, but the fan never came on to cool it.

The mechanic said it could be one of several things, most likely an electrical problem.

Do you guys know where I should begin? The fan turns on when I turn the A/C on, so I know the fan is working. The problem is, a signal is not being sent to the fan when the engine is running hot.

Any suggestions and pointers?

Thanks in advance.

 

coolant temp sensor? fuse?

 

I should also mention that my auto repair skills are non existent

edit: Also, I drive a 2001 TL

 

fan sensor, passenger side lower corner of radiator,
they go bad and the driver side fan wont come on, or it comes on and wont turn off when you shut the car off!

the passenger side fan is coupled to the ac,
the driver side fan is temp controlled by the radiator temp sensor

Have your guy replace that sensor, then make sure there are no air bubbles in the coolant system -per the book
Here is the free owner book link- click your cars year then model-
I drive an 01- the air burping/bleeeding procedure is lengthy and involves various rpm and fan coming on and off etc- read and follow exactly or air will mess you up- turn heat to full hot for procedure,
the heater core is a small radiator with coolant in it, as part of the overall coolant system and likes to trap air if forgotten during a coolant change or work when the radiator is opened
https://techinfo.honda.com/rjanisis/...01_OMANUAL.asp

 

Also, the thermostat failing can cause your sensors to not sense the true temp and therefore your fans will not kick on. It is also an cheap and easy fix.

As for the pass and ddriver fans, does this change w/the type S or with the style update, because mine are either both on or both off. hit the AC, and they both come on. temperature cycle, they both come on.

 

Im sure it varies with year and model- I believe (like I am never wrong~) the AC fan backs up the primary cooling fan `when needed`- but thats on my year
Its probably in the owner book, but that would require reading to get correct info

Thermostat is definetly a possibilty if the temp has gone hot then cools suddenly then hot...or stays hot or necver gets any temp, and the fans appear to be working- then suspect thermostat first
If fan(s) always on or not at all- suspect sensor unit

 

the type S with its 35 more HP may require more cooling and kick both fans on at once