Radiator Fan NOT Switching On

brightonian · Post by **brightonian** » Sat Apr 07, 2007 4:55 pm

Hi guys,

My radiator fan isn't switching on.... I have a 406 August 1999 T Plate 2.0 petrol.

Two questions really:

a) Is it computer controlled these days (or is it nice and simple like the "good old" days!)?
b) Where is the water temperature sensor located?

Finally, how easy is it to "get" to the front of the radiator, where it is located. I had a quick look and it seemed that there appeared to be a (limited?) amount of bodywork removal.

Ok, that's three questions! Thanks in advance for any help

Steve

jameslxdt · Post by **jameslxdt** » Sat Apr 07, 2007 5:39 pm

is it a d8 or d9?
as its a 1999 it may be either, or a strange d8.5, but if its a d8 then most likely it will be the both cooling fans and the 3 relays, does your car have aircon?

brightonian · Post by **brightonian** » Sat Apr 07, 2007 5:51 pm

jameslxdt wrote:is it a d8 or d9?
as its a 1999 it may be either, or a strange d8.5, but if its a d8 then most likely it will be the both cooling fans and the 3 relays, does your car have aircon?

Hi, sorry, it's the latter model (D9?), has aircon.....

philmeboots · Post by **philmeboots** » Tue Apr 17, 2007 4:53 pm

Hi, sorry first post so thought I'd join in on this thread as it seem related and same model etc...

I've got a 99/v 2.0 GTX and it seems to have the same problem... fan wont come on... On closer inspection, mine only appears to have 1 single fan BUT it has a/c!

I'm confused!

Looking for some tips of how to fault find - sensor being first bets (temp sensor on dash seems to be spot on so is there a seperate sensor for the fan or should I jump to the relay area?) Obviously failing that it could be the fan/motor itself?

Any help much appreciated!

Post by **Welly** » Tue Apr 17, 2007 5:10 pm

There is only one fan on the D9. I had to replace mine last year (fan=£120.00) the ECU/Climate Control tells the fan what to do.

It is variable speed whilst doing the a/c and full speed if interupted by coolant temp. Sometimes it's full speed on a/c if it's really hot outside.

When my fan started wearing out it overheated a 40 amp fuse in the engine bay fuse box and called up an ECU engine management fault.

Maybe check the fuses first, I could tell where mine had been overheating as it was discoloured a bit.

Can't remember the fuse number at the moment

There is also some relays fitted behind the fan cowling and you can see the wiring connections through your front grille - these have been known to break down due to water ingress. Again, another favourite to check out.

Hope this helps.

mjb · Post by **mjb** » Tue Apr 17, 2007 6:33 pm

Would it not be an idea to find the coolant temperature sensor (bottom of the header tank?) and short the wires to simulate "infinitely hot"? With the ignition on but the engine not running, logically you should hear the click of the fan relay when the wires are shorted?

philmeboots · Post by **philmeboots** » Wed Apr 18, 2007 11:01 am

Thanks for the replies so far - Its only overheated twice when sat in traffic, the big STOP light came on and you I got the "Engine temp too high" warning on the display console. I turned all the cabin fans on full blast and hot which cooled it down pretty quick!

Now I've sorted out the 1 or 2 fan mystery I can dig deeper - fuses & relays being checked tonight

Post by **Welly** » Wed Apr 18, 2007 11:47 am

Have a look at this old post I remember, unfortunately the piccies have gone but hey, it might help.

viewtopic.php?t=1452&start=0&postdays=0 ... highlight=

philmeboots · Post by **philmeboots** » Wed Apr 18, 2007 12:34 pm

Excellent - thanks for that Welton, it should save me plenty of time!

After reading that it kinda makes a lot of sense as I have had a good look around the area and have noticed a build-up of debris (leaves, dirt etc..) under the radiator so chances are the wiring/connector has gone - I've got my fingers crossed that it isnt the fan itself!

philmeboots · Post by **philmeboots** » Thu Apr 19, 2007 12:57 pm

OK, fan seems dead with a/c ON or OFF but it will turn by hand... Now, before I go dismantling things and checking wiring etc... can anybody advise me which is the fuse for the fan so I can check that first?

I guess there aren't that many 40amp fuses so should I just check all of them?