Bitron Unit for early Xantia

chasqui · Post by **chasqui** » 05 May 2009, 17:06

Thanks DickieG for the advice. Yes.. Mine is the MK1 and there are no numbers on the temperature control. So I guess mine is the same as your 93 VSX TD.. The air con is either on or it's off. There is no temperature settings.

Post by **xantia_v6** » 05 May 2009, 18:21

I have not found my spare bitron (it is probably in a box in the loft), but it is more likely to be the middle of the 3 variants (because it came with a control panel which has Auto and Off positions for the fan).

Was the early Bitron used on other models? e.g XM or BX?

Clogzz · Post by **Clogzz** » 06 May 2009, 05:49

The Bitron that spins the fans is the right one.
If the overtemperature light is on, the fans must spin at the high speed.
The light comes on when the brown sensor is too hot or disconnected.

On the maps that we have, the brown sensor has two wires going to Bitron pins 7 & 14.
The earliest vintage had a single wire sensor, and was quickly modified for free in France.
I’ll dig up the modification tonight local time.
Modified or not, the sensor must measure about 1800 Ohms at cold, and over 3500 Ohms when hot.

chasqui · Post by **chasqui** » 06 May 2009, 06:10

Thanks for your reply!

My brown sensor has the 2 connectors. I'll check the resistance later this morning.

I do recall tracing the wiring from the sensor back to pins 7 and 14.

I'l report my findings later!

Thanks again

addo · Post by **addo** » 06 May 2009, 12:07

I've just been playing "Boil your Bitron" and found the cold temp around 1.8KΩ, but in a pot of boiling water it only made 2.6KΩ or so. Does it need to crack about 105°C to reach 3.5KΩ?

Clogzz · Post by **Clogzz** » 06 May 2009, 12:27

Hi chasqui,

My Bitron goes:

PP-TD30 … probably the plastic’s recycling code.
CCT 4/TPA
9614696180

So, if you have one like that, and it does make the fans spin, it’s still the wrong one, because it’s for the air conditioner with a temperature slider going from 18 to 26 degrees, and a blower speed slider with “auto”, “off”, and 4 manual speeds.

Of no use by now, but if there’s any interest, here’s the link to the brown sensor modification.
It’s in French, but we lot look at the pictures.

http://xu10j4r.free.fr/xantia/notexantia.pdf

And hi Adam,

Your car is the late version that Richard refers to; different to mine, where after two short trips in less than an hour by hot weather, the sensor was measuring 3780 Ohms.

addo · Post by **addo** » 06 May 2009, 22:10

Thanks for the links. I was actually testing the 405's sensor while I have it all apart (the car presently has a manually switched fan control). The simple diagrams on that page actually clarify what's in the blue sender - a nice touch.

chasqui · Post by **chasqui** » 08 May 2009, 06:31

Clogzz.. thanks for your advice and for the info on the modification.

Just tested my brown sensor.. when cold reads 1789ohms.

When hot to the point where fans should be on, it was 3589ohms.

I tested this twice. First time directly on the contacts of the unit. Second time with the plug in place and testing across points points 7 and 14 on the conector to the bitron box.

I don't think this is at fault.

So, does anyone know anywhere in the world where I may get a replacement bitron unit for my early xantia please? (for less than £150!!)

DickieG · Post by **DickieG** » 08 May 2009, 08:14

chasqui wrote:So, does anyone know anywhere in the world where I may get a replacement bitron unit for my early xantia please? (for less than £150!!)

Try http://www.edwardsandson.co.uk/

MikeT · Post by **MikeT** » 08 May 2009, 09:51

addo wrote:Does it need to crack about 105°C to reach 3.5KΩ?

107 is when full speed fans are supposed to come on, if that's what you're asking.

chasqui · Post by **chasqui** » 11 May 2009, 07:32

At last! problem solved.

There was a problem with a broken wire into one of the connectors to the switching relay near the fans. This was causing the fans not to work at high speed and the orange temp warning light to come on.

This wouldn't have been diagnosed or repaired without your help. The wiring diagrams proved invaluable.

Now my alternator has gone faulty!!! Still, that's an easy one!

Thanks again

Post by **CitroJim** » 11 May 2009, 08:21

Excellent

Very pleased to hear it!!!

rolyh · Post by **rolyh** » 30 Oct 2012, 15:44

Anyone know where the bitron sensor is on a Xantia V6?

Rolyh

Post by **CitroJim** » 30 Oct 2012, 17:23

rolyh wrote:Anyone know where the bitron sensor is on a Xantia V6?

Rolyh

I've answered in your other thread Roly

Cui Alex · Post by **Cui Alex** » 26 Aug 2023, 02:34

Clogzz wrote: ↑04 May 2009, 13:36 Welcome to our fan troubles, chasqui.

It’s not likely to be the Bitron, we’re indeed well used to pulling out rotten wires.
If you put contact 1 of the Bitron socket to earth, both fans should go to low speed, even with the key out.
If they don’t, it’s not the Bitron at fault.
If you earth contact 10 with the key set to accessory or ignition, both fans should go to high speed.
If they don’t, it’s still not the Bitron.

Oops, Jim ! I wrote this before I saw your last post.

Hi everyone, my name is Alex.
I'm bringing this discussion back to life because my peugeot 106 GTI has the same 15-pin relay as this discussion.

I wanted to ask if it was possible to post the briton sensor diagram again, it would be of great help to me!

(I tried to ground pin 1 and pin 10 as recommended. with pin 1 the fans both turn slowly, but with pin 10 I hear the other relays trip but the fans remain still.
I also tested the marrine sensor cables Pin 7 and 14, these are also intact, but I don't know the destinations of the other pins).

Thank you!

French Car Forum

Bitron Unit for early Xantia

Re: Bitron Unit for early Xantia

Re: Bitron Unit for early Xantia

Re: