xantia heater control problem

_kid_ · Post by **_kid_** » 23 Jul 2006, 21:58

The xantia has developed a problem with the heater control temperature slide.

when i slide anywhere from 18 to 26 ambient air comes out. When i slide it right to the warm extreme (i.e. past 26 to the very end) suddenly v hot air comes out. It the same with the air con-except it comes out cold on the cold setting.

I can also hear the ‘buzzing' noise when i move the temp slide. Ive looked under the heater panel and can see movement from the dial.

I have tried rebleeding the coolant again, the fans come on as they should, the two heater hoses are hot.

I have only noticed this problem yesterday when it was cold. Last winter even at 22 there was enough hot air coming out.

citroenxm · Post by **citroenxm** » 23 Jul 2006, 22:18

Hi kid

The buzzing I guess is the TINY fan assisted Temp sensor, that sists behind the Alarm LED left of the clock. It could be playing up and not sending the correct signals to the heater depending on the setting you select.

Fully cold and FULLY hot over rides the temp control.

Try changing that first

Regards
citroenxm

_kid_ · Post by **_kid_** » 23 Jul 2006, 22:22

citroenxm wrote:Hi kid

The buzzing I guess is the TINY fan assisted Temp sensor, that sists behind the Alarm LED left of the clock. It could be playing up and not sending the correct signals to the heater depending on the setting you select.

Fully cold and FULLY hot over rides the temp control.

Try changing that first

Regards
citroenxm

There is that buzzing coming from the temp sensor, but there is also another buzzing. When i move the heater control slider a quiet buzzing comes from the glovebox area, i believe this shows the temperature adjustment is being registered.

Post by **Peter.N.** » 23 Jul 2006, 23:41

The buzzing from the glovebox area is the flap control motor which is running in response to your moving the temperature control, proves its working at least. All of my XMs have gone to maximum heat output once advanced beyond 26C. The heat output is very subjective depending on the ambient temperature and your temperature. Sounds as though it working OK to me.

_kid_ · Post by **_kid_** » 24 Jul 2006, 01:56

Peter.N. wrote:The buzzing from the glovebox area is the flap control motor which is running in response to your moving the temperature control, proves its working at least. All of my XMs have gone to maximum heat output once advanced beyond 26C. The heat output is very subjective depending on the ambient temperature and your temperature. Sounds as though it working OK to me.

Unfortunately I don’t believe it’s working ok. As i say last winter when i place the slider on 22 there was plenty of hot air coming to the cabin, there was no need to put the auto setting on, the 22 did the job on manual low speed. Now it’s a coolish breeze right upto 26, then the extreme of 26 the heat is intense. Clearly the fact the heat is hot from the end of the hot range suggest the cooling system is ok. Infact everything works on the control unit with the exception of the temp slider.

Re the interior cabin sensor, i did clean it out a few months ago, i can’t remember if the slider was working ok after that.

Also re the interior cabin sensor how does this work? Ive tried on auto and 22 i would expect some hot air initially but all im getting is ambient.
What about when the fan is set on manual speed, does the cabin sensor still dictate the temp through the vents despite the manual speed setting?

With this warm weather i have not required testing the hot temp, but the air con is working ok, could it therefore be the cabin sensor is stuck on cold

mezuk04 · Post by **mezuk04** » 24 Jul 2006, 08:39

My xantia started doing that, I could either have FULL COLD or HOT and FULL HOT.

There was no adjustment of temperature between cold and mid temperature, it was just warm all the time

Post by **Peter.N.** » 24 Jul 2006, 09:35

Well, the flap motor is obviously working, otherwise you wouldn't be getting the change from 'hot' to 'cold, if there is a fault, it must be in the sensor / control panel. You could try swapping the panel or even the sensor for one from a scrap car. But you wont get any heat from it unless the setting of your control is above the ambient temperature, so at a setting of 22C the heater will still blow cold air if the temperature inside the car is allready 22C, and it hasn't been much below that lately! 8)

Post by **RichardW** » 24 Jul 2006, 09:53

It'll be the temp sensor, as Malcom says. Most likely the fan has stopped going round, and the heat from the stalled motor / the radio is giving it a false reading. I have the sensor hanging out of the dash, cable tied onto one of the heater control screws for just this reason. It's been like that for about 8 months now - can't bring myself to part with £100 for a new one from Citroen

It works OK - there's a bit of lag in adjusting the temperature, but I just ignore it and let it get on with it.

Post by **Peter.N.** » 24 Jul 2006, 12:03

I would have thought there would have been plenty of scrap ones about.

_kid_ · Post by **_kid_** » 24 Jul 2006, 19:33

Thanks again, will look at the motor later, to see if it’s spinning

however i still am not sure how the system works.

Say if i put on AUTO and set to 22 in the current heat, then yes i agree, there will be coolish air coming from the vents as the climate system and cabin sensor together aim to lower the inside temp.

Now say if i switch the fan to the manual speed setting and 22 surely i have overridden the cabin sensor, and there should be 22C coming from the vents whatever the weather

Post by **RichardW** » 25 Jul 2006, 07:30

No, the temp setting is only related to the air temp in the cabin, and switching the fan from auto to manual does not turn off the auto temperature regulation. I'm pretty sure that if you shine a torch down the grille by the alarm LED and turn the ignition on and off you will find the fan merely kicks but does not spin.

Unfortunately there's a dearth round here of a)MK1 Xantias with climate b) Mk1 Xantias with climate in scrapyards c) scrapyards and d) MK1 Xantias with climate where the fan isn't knackered. So, a new one is the only option for me. Since I'm tight however, and it works fine hanging out the dash, it can stay that way!

_kid_ · Post by **_kid_** » 25 Jul 2006, 12:19

RichardW wrote:No, the temp setting is only related to the air temp in the cabin, and switching the fan from auto to manual does not turn off the auto temperature regulation. I'm pretty sure that if you shine a torch down the grille by the alarm LED and turn the ignition on and off you will find the fan merely kicks but does not spin.

Unfortunately there's a dearth round here of a)MK1 Xantias with climate b) Mk1 Xantias with climate in scrapyards c) scrapyards and d) MK1 Xantias with climate where the fan isn't knackered. So, a new one is the only option for me. Since I'm tight however, and it works fine hanging out the dash, it can stay that way!

Thanks for clearing that up, ill try electric contact cleaner first (assuming the fans not working)

Btw the good news is its not £100, the bad news is its still £57+vat according to Citroen

http://www.citroen-pr.net/catalogues/il ... 443100.gif

dnsey · Post by **dnsey** » 25 Jul 2006, 12:50

In this weather (I assume that you're in the UK), I wouldn't expect any heat except at maximum setting, as the cabin temp is probably well over 26C anyway - that's the point of climate control

However, the aircon should of course kick in instead to lower the temp, so there's clearly a fault of some sort.
Edit: just noticed that you tried it on a 'cold' day - did you check the actual air temp, as it can be very misleading when it's been as hot as recently?

_kid_ · Post by **_kid_** » 25 Jul 2006, 14:29

dnsey wrote:In this weather (I assume that you're in the UK), I wouldn't expect any heat except at maximum setting, as the cabin temp is probably well over 26C anyway - that's the point of climate control
However, the aircon should of course kick in instead to lower the temp, so there's clearly a fault of some sort.
Edit: just noticed that you tried it on a 'cold' day - did you check the actual air temp, as it can be very misleading when it's been as hot as recently?

i tried with the evening with air con on, setting to 26 still the air was cold, so clearly something is not right.

_kid_ · Post by **_kid_** » 26 Jul 2006, 00:44

_kid_ wrote:
dnsey wrote:In this weather (I assume that you're in the UK), I wouldn't expect any heat except at maximum setting, as the cabin temp is probably well over 26C anyway - that's the point of climate control
However, the aircon should of course kick in instead to lower the temp, so there's clearly a fault of some sort.
Edit: just noticed that you tried it on a 'cold' day - did you check the actual air temp, as it can be very misleading when it's been as hot as recently?

Had a look today and the fan is spinning, ive wd40'ed it and it is whisper quiet (for now at least) but there is no difference in the temperature control slider. I will wait till it becomes cold and report back