Climate control sensor and fan

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MikeT
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Post by MikeT »

Thanks RichG, most informative. Do the connections need to be unlatched in any way or can a good tug work without breaking anything, I haven't got a light in there to see what's what yet?

I could only get a price for the one unit but it's way too much for me.
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Post by MikeT »

admiral51 wrote:depends if you have an honest face :lol: :lol:
That's me sunk then 8)
admiral51 wrote:if i go weekend ill pm you and let you know whats up there

i may have space myself :lol: :lol:

colin
Great 8) Rear silencer, rear nearside abs sensor, steering wheel, alarm module & interior sensors, pin number pad (or the number one button :lol: ), air con switch that illimunates brightly, full interior trim "Cananga Velvet" including seats and door cards, radio/cassette, wheel brace, four undented wheels (steels ok), rear ashtray, parcel shelf with good cords and blinds, a spare remote controller, throttle cable, steering rack erm... sure there's more...
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Post by RichG »

MikeT wrote:Thanks RichG, most informative. Do the connections need to be unlatched in any way or can a good tug work without breaking anything, I haven't got a light in there to see what's what yet?

I could only get a price for the one unit but it's way too much for me.
The unit can be pulled forward without disconnecting the wires so that you can see what you are doing. It cannot be removed from the fascia without disconnecting the plugs.

Part No. C6552EA is without the LED at about £58.00. C6552HF with the LED is about £87.00.

I have heard of people removing the thermocouple from the unit and leaving it dangling from the dash into the cabin. They say that this works as the thermocouple is then at cabin temp without having to use the little fan to draw air over it.

Richard
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Post by admiral51 »

seems a pretty straight forward shopping list wish the wifes was as short as that shes started using A4 both ruddy sides :lol: :lol:

ill look and see whats available just as well i got hgv1 plenty of room left on trailer if anyone wants to add some more.................... :roll:

colin
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Post by MikeT »

RichG wrote:...I have heard of people removing the thermocouple from the unit and leaving it dangling from the dash into the cabin.
Richard
There's always the cut-n-splice method if I can't get the plugs off.

As nice as it sounds - just letting it dangle freely in the breeze 8) - I'm just a little more reserved to be doing that. :lol:
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Post by MikeT »

admiral51 wrote:..just as well i got hgv1 plenty of room left on trailer if anyone wants to add some more.................... :roll:

colin
Well a bonnet and four doors could be useful and a windscreen wouldn't go amiss :lol:
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Post by admiral51 »

hi mike

its no good adding to the list with only half the information

red,blue,green,grey,black,silver :?: :?:

colour coded mirrors :lol: :lol: :lol:

colin
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Post by RichardW »

To put the record straight here.....

Yes the fan should run all the time the ignition is on. It's not straightforward as having no voltage - it seems to use some sort of modulated signal to make it run (presumably to keep it quiet) and what seems to happen is that the electronics give up which causes the fan only to kick when switched on and not run.

Although the sensor is the same between MK1 and Mk2 cars (indeed I think it is also fitted to many other PSA cars), the fitment is different. On MK1 cars the sensor is clipped into the alarm LED and can be removed in one piece (although on my car I needed to remove the radio, surround and clock in order to lever it out). There are clips on top and bottom of the alarm LED / grille that hold it in. Getting the clip off that holds the cable connector to the side of the radio housing so that you can undo the connector is also a trial! Once the sensor is out, it's possible to separate the LED / grille from the temp sensor (carefully prise the clips back then ease the sensor out - the actual temp sensor sticks out about 50mm on a piece of fragile PCB...) On Mk2 cars the front housing is all in one piece with the clock and sensor grille, and on these cars (in theory) you need to remove the whole piece before removing the sensor off the back - to do this you need to remove the steering wheel as there is a clip (or screw, can't remember which) in behind the steering column shrouds.

I think the part numbers given above are a bit misleading - the expensive bit is the fan bit, and you need this for any car. Expect your dealer to have trouble finding it on their parts computer - I think you need to look under alarm rather than A/C :wink:

I can confirm however, that if you are not bothered about what it looks like, you can hang the sensor out next to the heating controls where it works just fine without the fan - mine's been like this for about 18 months now. Another alternative is to blu-tac a CPU cooling fan onto the front of the grille, powered off the lighter socket (there was a photo on here of this arrangement a while back). I might not be so tight on the next car and buy a new one when it goes down....!
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Post by Clogzz »

2002 C5 2.0i AL4 230,000 km 76372389
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Post by MikeT »

admiral51 wrote:red,blue,green,grey,black,silver :?: :?:

colour coded mirrors :lol: :lol: :lol:

colin
I do like flip paint on some curved vehicles but if you can't find that, I've always favoured fire-engine red. My car is white but a change is as good as a rest :lol:
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Post by MikeT »

RichardW wrote:...It's not straightforward as having no voltage - it seems to use some sort of modulated signal to make it run (presumably to keep it quiet) and what seems to happen is that the electronics give up which causes the fan only to kick when switched on and not run.
That's exactly how mine behaves - where is the electronics that give up, is it inside the sensor fan motor or elsewhere? I decided to put it all back together without a chance of fixing it and ended up breaking a fragile plastic clip and one rubber half o-ring broke in two as well :?

Although my climate control isn't working as it should, I can still get the hot or cold air I need manually so it's not exactly a critical concern.

Many thanks.
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Post by CitroJim »

MikeT wrote:Although my climate control isn't working as it should, I can still get the hot or cold air I need manually so it's not exactly a critical concern.

Many thanks.
The only problem you'll fine Mike, is that in the dark depths of winter it'll start blowing hot and cold :( as the system will tend to pick up the under-dash temperature (especially from the radio) and over compensates for the heat it finds there. It makes a very uncomfortable climate. I found this out as my fan/sensor had dropped out of its mount and was hanging down behind the dash very close to the top of the radio.

On full hot or full cold no problem as the sensor is disregarded at the two extremes.

These days you can get some very tiny CPU fans, especially those used to cool northbridge and graphics card chips. Some of these are naked and should, with a bit of ingenuity, fit.

I found mine was initially jammed because it had a lump of unidentified plastic debris in it. It must have sucked it in at some point.
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Post by MikeT »

citrojim wrote:..as the system will tend to pick up the under-dash temperature (especially from the radio) and over compensates for the heat it finds there.
That's ok Jim, I got no radio fitted 8)
citrojim wrote:..On full hot or full cold no problem as the sensor is disregarded at the two extremes.
That's that what I'm used to anyway - never had climate control before now
citrojim wrote:..These days you can get some very tiny CPU fans, especially those used to cool northbridge and graphics card chips. Some of these are naked and should, with a bit of ingenuity, fit.
I was thinking of that idea too but without being able to disconnect the damn thing without risk of breaking it further, I've reassembled it and will carry on using the heating on manual. Cheers
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Post by CitroJim »

MikeT wrote:
citrojim wrote:..On full hot or full cold no problem as the sensor is disregarded at the two extremes.
That's that what I'm used to anyway - never had climate control before now
:lol:

Heat full on and you'll roast Mike, if your matrix is in good nick. The heater is seriously good!
Jim

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Post by MikeT »

RichardW wrote:To put the record straight here.....

Yes the fan should run all the time the ignition is on. It's not straightforward as having no voltage - it seems to use some sort of modulated signal to make it run (presumably to keep it quiet) and what seems to happen is that the electronics give up which causes the fan only to kick when switched on and not run.
I managed to get the thing unplugged today and it looks as if you're correct about the electronics side failing. I noticed even though the fan wasn't turning the module had got almost hot to the touch after about 10 mins driving proving it's getting plenty of power.

Applying 12V direct to the plug gives the same behaviour as when fitted so it's obviously not a power feed fault. I'm not sure which of the four terminals I need to connect to test the fan motor direct but it's more likely the pcb has failed - what's there, three capacitors and a resistor? If I knew for sure I'd desolder them and get new replacements for a few quid.

Failing that, could I bypass the circuit using a resistor to keep it quiet? Again, I need to know where to feed the motor as I see two pairs (4 terminals) coming from two ends of the coil.

Thanks
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