Xantia V6 Overheating

xantiatdsx · Unread post by **xantiatdsx** » 04 Jul 2006, 19:40

Hi, I have noticed in the summer heat that when i dont use the 2cv the Xantia overheats very quickly and requires me to sweat my nads off with the fan on hot and full blow to keep the tempertature under 110degrees. it can be when slow driving or stopped. I stopped where i was able to today and the fans do not work what so ever!
The radiator closest to the engine was changed in april 05. When you feel the rads after running the front one feels cooler than the one near the engine by a long way. Why does it have 2 rads and what do the 3 relays in the middle of the fans do? is there anyway to easily test thefans like on a bx where you can bridge the fan switch or is it way complicated?
The rad fans do not come on if the aircon is on but the aircon works lovely, nice and cold still.
Thanks
TIM

LeeDJC · Unread post by **LeeDJC** » 04 Jul 2006, 19:55

I don't know the V6 setup, but I assume the one nearer the engine is in fact an oil cooler.

If my car was overheating, the first thing I would check is the thermostat. If the rad is cold, then I guess the thermostat is seized shut. Try removing it and running it without, if that solves the problem, then look at replacing it before the weather gets cold again.

If that's OK, I'd flush the cooling system through (particularly the rad) with a hosepipe. It generally flushes better if you flush it backwards to the usual flow.

Hope this helps

Unread post by **xantia_v6** » 04 Jul 2006, 20:20

I stopped where i was able to today and the fans do not work what so ever

If your fans are not running, there is no point looking for any other cause of overheating.

Why does it have 2 rads

The front "rad" is the air conditioning condenser, which in no way helps to cool the engine.

what do the 3 relays in the middle of the fans do?

The fans and relays are wired to run the fans in series at low speed when the air conditioning is switched on with the engine cool, and in parallel at high speed when the engine gets hot.

The cooling system is controlled by an electronic box called the Bitron controller. Search the forum for Bitron to learn more.

xantiatdsx · Unread post by **xantiatdsx** » 04 Jul 2006, 20:35

thanks, searching and learning now.
let you know!
TIM

xantiatdsx · Unread post by **xantiatdsx** » 04 Jul 2006, 20:58

HI, Where is the brown connector on the thermostat housing on the v6?
i have the left headlamp out, airbox out and i still dont know what im supposed to be seeing....
Think i will try and test the relays tomorrow or find replacements....
btw, should all the relays be black?
scrap heap challenge here we come!

how many pins should each relay have?
mine all have 5

8304 · Unread post by **8304** » 05 Jul 2006, 08:47

hi

im not sure with the xm's but the twin cooling fans on my zxm stoped working and it turned out to be the radiator switch - they are cheap so it might be aswell to change it anyway......

i think the xm uses the bitron unit but i dont know anything about it but CLOGZZ seems to be well clued up on this problem with xantia fans so it would be well worth gettting his opinion....

if your fan switch has three pins coming out of it, by connecting one to ground the fans will start but this doensty prove the switch i functioning because it may be that with age it is now operating at too high a temperature - (the switching temeperature increases with age as they wear out)

good luck

xantiatdsx · Unread post by **xantiatdsx** » 05 Jul 2006, 12:21

I know about fan switches on BX 16v's but does the xantia v6 have one? I dont know?
Anyone any ideas? Its just started raining so the scrap yard will be browsed in the wet after work.
TIM

Clogzz · Unread post by **Clogzz** » 05 Jul 2006, 13:46

xantiatdsx wrote:Where is the brown connector on the thermostat housing on the v6?
should all the relays be black?
how many pins should each relay have?
mine all have 5

The brown sensor is probably at the back, out of sight and reach.
If all 3 relays are black with 5 pins, thay are all the same and can be swapped all around.
Ideas here:

http://www.frenchcarforum.co.uk/forum/v ... hp?t=19296

http://www.frenchcarforum.co.uk/forum/v ... hp?t=19090

http://www.frenchcarforum.co.uk/forum/v ... hp?t=18965

http://www.frenchcarforum.co.uk/forum/v ... hp?t=14682

http://www.frenchcarforum.co.uk/forum/v ... hp?t=17012

http://www.frenchcarforum.co.uk/forum/v ... hp?t=18871

Unread post by **Peter.N.** » 05 Jul 2006, 14:05

The fans don't have much effect when you are travelling at 30 mph + the air ram effect should be sufficient to keep the temperature down. If it is overheating at speed, check the thermostat first as already mentioned, if that is OK the most likely problem is a clogged radiator. If its done 100k or more it will probably need replacing. If it only overheats in traffic the the lack of fan function would be the obvious problem.

Quackers · Unread post by **Quackers** » 05 Jul 2006, 15:44

Have you tried poking the fans with a stick when the car hits 90C? I have a V6 Xantia and mine overheats because the fans do not kick in. Poke the fan and they spin as they should.

Stempy · Unread post by **Stempy** » 05 Jul 2006, 17:12

The brown temp. sensor is on the thermostat housing, you'll probably need to lift the airbox to see it. They do go faulty but mine went the other way and switched the fans on all the time.

The Bitron cooling control module on the V6 is in the box with the engine and suspension ecu.

The fans should run continually at low speed with the aircon on and only speed up when the engine temp reaches about 105ºish.

It's worth having a look around the relays. If you pull the plastic lids off you can manually activate them and you should be able to get the fans spinning, this would prove that there is a supply reaching them. If that's the case then the problem lies in the control circuitry.

xantiatdsx · Unread post by **xantiatdsx** » 05 Jul 2006, 18:57

It had a new rad last year before i got it. I changed the relays fro some i found at the scrappers but still nothing when the aircon is on and the engine ticking over.
I have the air box out , is the brown sensor behind the green wires into the side of the engine?

where are the other ecu's and what is the box under the lhs light?
Thanks
TIM

f00lzz · Unread post by **f00lzz** » 05 Jul 2006, 19:08

xantiatdsx wrote:The rad fans do not come on if the aircon is on but the aircon works lovely, nice and cold still.
Thanks
TIM

I'm amazed

Surely the A/C doesn't kick in if the rad fans aren't blowing air across the condenser!!!

xantiatdsx · Unread post by **xantiatdsx** » 05 Jul 2006, 20:25

hooray! changed the relays and nothing, found both bitrons in the ecu bit of the bonnet, unplugged all and still nothing.
The bitron under the lhs light could not be removed but using a screwdriver carefully i could remove the plug, this felt very gritty and corrosion could be seen on the pins. afer workin the plug in and out over and over i plugged it back in and hey presto it works! fired the car up, A/C on and the fans come on, a/c off and they go off. nicely done.

Thanks for all your help!

TIM

yeh, i got my car back!

oh, one last thing.... is there anything missing from here?

AndersDK · Unread post by **AndersDK** » 05 Jul 2006, 20:43

No - nothing is missing there according to PR-net online :
http://www.citroen-pr.net/catalogues/il ... 700500.gif

This stud is located on the clean side of the air intake. Suppose at some time it was intended for any intake vacuum device.
Can you feel suction on this stud ?
Sometimes they just left such studs in the casting - blanked off.

French Car Forum

Xantia V6 Overheating

Xantia V6 Overheating

Re: Xantia V6 Overheating

sorted!