Overheating...

[Matty-O]

Ok...so in normal driving conditions, my car is absolutely fine...highway, suburbia, etc. my cars fine...But, once i hit traffic i start to overheat like crazzyy, I have to turn on the heater i order to bring it back down and have it on(and, the heater sometimes doesnt help) so in conclusion, HELP!

[Gotturbo]

#1. Is you coolant filled?

#2. Is your fan turning on?

#3. If it isnt have you checked all connections to it?

Thats if for now answer some of them then you can go from there.

[MKIIVR6]

#2. Is your fan turning on?


Word. Check it for sure.

[Salteatervw]

wow for a car that new, i would say get your rad flushed and add new coolant but thats just me

[GoodDayForADrive]

This reminds me... I need to fix my coolant leak before stuff like this happens...

[Gotturbo]

Yea one of my wires came unsotered in one of the plugs and my fan wasnt getting turned on so it was overheating for like 3 days then I finally found the wire I was so happy!

[Salteatervw]

my rabbit overheated it die but im bringing back from the dead.

[jettadude]

if you turn on the ac the fan will turn on. it will cool it faster then useing the heat. that is if the fan is turning on.

[Matty-O]

Could the fact that the AC isn't working be a factor?

And how should I go about checking the working ability of these fans or is it as simple as turning the car on, lifting the hood, and looking...?

[GoodDayForADrive]

Could the fact that the AC isn't working be a factor?

And how should I go about checking the working ability of these fans or is it as simple as turning the car on, lifting the hood, and looking...?

On my car, you can see the fan spinning, I don't know about mk4's though

[Gotturbo]

Just go drive around till the car is getting hot then pop the hood and the fan should be on... Its easy to tell if it is or not you can hear and see it.

[Salteatervw]

if you had a scan tool you can turn on the fan manually it's pretty cool to do.

[burn_your_money]

Since it cools down when the heater is turned on I would imagine it is the rad fan not turning on. Just drive it until it is up to normal temperatures, then stop somewhere pop the hood (engine running) and within 2 minutes the rad fan should kick in.

[Matty-O]

Is this an easy fix if the fans arent turning on because i dont believe they are? Or do i need a mechanic to do it for me?

[jettadude]

well if the motor isn't burnt its just a switch or a relay. finding the prob is gonna be a pain thou.

[Salteatervw]

maybe a bad connection due to corrsion, try diconnecting the fan relay and cleaning it and see what happens.

[burn_your_money]

I don't know how your fan is wired, but when I had to figure out what was wrong with mine I just took a piece of wire and stuck it in where the rad fan sensor is (closing the circuit and activating the fan). If that doesn't turn the fan on, you know your sensor is good. I'd then jumper the fan directly to the battery ( - and + don't matter, it just determines which way the motor spins). If the fan motor comes on then you have a wiring issue or relay issue. Try pulling the relay and jumpering the terminals that run to the rad sensor AND also jumper the sensor wire like in step one. If the fan comes on then you probably need a new relay, if it doesn't you get the fun job of tracing all the wires.

Before you do anything though replace the fuse, even if it looks good it might be crapped out, I found that out the hard way.

For the record I've never looked under the hood of a MK4 so use alot of caution/descresion when following my advice.

[josef4334]

hello guys.

i am having the same problem as matty-o. i checked my coolant and its fine. i ran the car in idle for a good half an hour and i didnt hear the fan turn on or see it turn on. my local dealer is telling me it could be the fan control module. where can i find this module in the engine bay? is this a hard do-it-yourself job? please help!

[Mr_Diesel]

Model, year and engine info would be helpful. Get back to us with those and we'll figure something out for you.

[josef4334]

its a 2001 jetta 1.8T. i found where the module was. it was a tight workspace. i kinda shook it and put it back. both fans turned on for a while then stopped working again. anybody have any idea about it?

[Mr_Diesel]

Did you shake the control module under the battery tray? That is where the module is. You must remove the battery tray to get to it. If you shook it and it work, then died, I'd suggest checking the connections for corrosion... if there is none, then replace the module.