Ok,

So some of you might know that ive got a problem with the bravo that the radiator fan doesnt turn on when it gets hot.

Now, I have taken the rad fan and assembly out completly for a better look and to understand exactly how it works.

First of all ou have the + and - to the fan motor itself. this is split to work via a relay and what I can only assume is the speed controller. Its a bigish round resistory looking thing.. ceramic feel to it and has started to crumble a bit anyway (suspect ).

Now, im assuming that the relay runs based on that a fan switch of some sort kicks (based on the temp of the coolant) and tells the relay it can now allow power through to the fan motor, which runs via the speed sensor.

and I correct?

The problem I actually have is that I cant find any sort of fan switch anywhere I have checked the fan motor and it runs and powers up when connecting it direct to the battery. ive checked the fuse which is fine. I have tried bypassing the speed sensor thing but to no avail as the fan switch hasnt been bypassed and so there is no current coming through anwyay.

so. where is the fan switch located on a 1.6 16v bravo with Aircon. It isnt on the radiator (or atleast ive failed to find it) and rather than pull the engine bay apart following wires, hopefully someone knows

Also, is it likely that the speed sensor could be faults as it has started to crumble slightly? Ide be able to work this out myself anyway if I could find the damn fan switch

thanks!

does your aircon work chris?

Hi there

Just to say if you do find that switch for the fan could you please let me know where it is, having the exact same problem with my bravo.

many thank
P

your not saying what year your car is?

ok top right hand side of the fan housing (looking toward the windscreen) you will see a connector joint, un plug this and bridge across turn ignition on fan should run when key is turned to ignition, fan will stop when key is in off position. the fan switch is located bottom left of fan housing. (try followning the cables from connector block)

the temp sensor is approx 10 inch in front of the connector block looks like a fancy spark plug this send the signals to ecu and temp gauge dash.

hope this helps

note the fan will constantly run if bridged this method when key is turned to ignition

yep i found the temp sensor.

Ive bought a haynes manual and it says that cars produced after april 1998 control the fan via the ECU and not a fan switch. Im pretty sure this is mine. as I definatly do not have a conventional fan switch screwed into the side of the rad. what Ive got sounds like what you have said UK_Yellow.

my car is a 1998 S reg. I dont know the exact production date.

Haynes says the fan will turn on just before the red on the temp dial. I left it today to go just into the red and gave up incase of engine damage. it defo doesnt turn on on the standard system. I did however directly connect the fan motor to the battery and it fired up fine.

Im beggining to think that the fan speed switch thing is at fault. this is the sensor on the bottom left hand side of the fan assembly. it was a bit crumbly and old looking. I have tried bridging this but no luck so im not sure. will replace it anyway and hope for the best

Is the only fuse for the fan the big one on the fuse box at the top passenger side of the engine bay under the cover that says "fuse" on it?

Cheers!

yeah that is the main fan fuse ( 40amp ) will find out more later and let you know.




Electrical engineer who just loves a challenge !!!!
P.s mine has the same problem...lol

You sure the temp sender isn't on right side of engine block just to the rear,think theres a plastic bracket over it.Never bridge out a sensor connected to the ecu.

yeah thats what i meant, if you look directly forward from the fan housing you will see the sensor on the engine block with 3 wires coming out, I havent bridged this and would never suggest it. I bridged the switch on the fan housing NOT the sensor.


Was a little tired yesterday so probably didnt explain it too well.

oh yeah i knew not to bridge that one. 3 wires is obviously something more than a simple switch so ive left it well alone

Still convinced it may be the speed controller on the fan assembly.

im gonna bridge the 2 wires on the connector block and the speed controller itself and see if the fan fires. if not then im still lost lol

Problem sorted!

It was the speed control sensor. The one on the bottom left hand side of the fan assembly.

Ive just bypassed it (bridged the wires) and the fan comes on perfectly at just over the middle mark and goes off once it drops bellow the middle mark (after about 10-15 seconds).

Its just a temporary fix as ill replace the sensor when I get a chance to get to fiat. I cant find one listed on the net anywhere so im gonna have to order direct.

Thanks for the help people

yeah mine is working exactly the same as yours now,i removed the sensor and basically give it a quick clean and as you know bridged that switch, next time i ran the engine the ecu must have got the message and hey presto !!

Happy Days

happy days indeed

do you mean the low speed coil? aircon might not work properly now...

yeah the speed thing. as for aircon.. works as it did before as the fan didnt come on anyway.

i expect it should be cooler which it probs will be when i replace the sensor as the fan doesnt come on with the aircon anyway.

I believe this is just what happened to me... Chack my thread here: https://www.fiatforum.com/bravo-technical/62332-now-what-overheating.html

The mechanic guy told me it was a faulty fan relay which caused the fan to run at a lower speed than it should... As I understand, the fan speed increases as the engine temp rises.

Do you have a bunch of relays sitting infront of your battery? I found out the problem with my marea was the connection to the bottom to one of the relays was corroded and needed to be re-made. Once this was done they ran the diagnostic program and both fans ran at both speeds