Next problem

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lexi
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Next problem

Post by lexi »

Right . Thanks to all for rad help on previous threads. All done.!

Cooling fans don`t seem to come in although when aircon is switched on the two fans come on ok. My slider fan control don`t work but last owner has fitted a rocker switch left of gearstick which works ok. Temperature can be changed ok with slider. Just wondered if these two things were related.

Fan motors must be ok. Maybe a relay at the front? (3 of).Any ideas thankfully accepted.

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CitroJim
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Post by CitroJim »

Hi Alex,

No, I'd say the two problems are not directly related. The fact the fans come on with the A/C is a good sign.

The fans are controlled by the brown Bitron sensor on the thermostat housing. This does sometimes fail but normally it fails open-circuit. A good test is to disconnect the Bitron sensor with the engine running. The fans should now operate at full-speed. Its a failsafe to guard against overheating should the sensor fail. The usual problem is bad connections to the little Bitron ECU that controls the fans. The problem is, it's a little inaccessible down under the nearside headlamp.

Clogzz is our resident specialist on these matters and I'm sure he will be along soon with all the information you need :wink:

The blower slider not working is more than likely the Xantia MK1 Achilles heel, the ignition switch. I'll expect you'll find the heated rear window is not working either as both the blower and HRW work off the same section of switch and both loads are a bit much for it. It throws in the towel. MK2 Xantias have a relay to supply these and it can be retro fitted quite easily. Colin (Admiral51) did it recently and posted about it. I'll search out his thread in a bit unless Colin beats me to it.

If the blower regulator fails, it normally fails to the blower fan running at super-cyclone speed irrespective of slider position. As always, it's worth checking all connections to the blower speed regulator module as it lives just under the fan and suffers from damp if the windscreen scuttle seal fails; Xantia Achilles heel No.2 :lol:

lexi
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Post by lexi »

Thanks Jim. Just to add that heated rear screen is working perfectly. Will check other stuff out.

Alex

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CitroJim
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Post by CitroJim »

Alex,

Pleased to hear the HRW is OK :D That should mean the ignition switch is OK unless some other wiring modification has been carried out...

What speed does your blower run at when you operate its switch?

Is is low, medium or super fast?

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Post by admiral51 »

lexi wrote:Thanks Jim. Just to add that heated rear screen is working perfectly. Will check other stuff out.

Alex
Hi alex
if i remember it is possible that the HRW will work even if the blower wont something to do with the amount of current it draws i think :oops: :oops: also does it really work i guess you have light on when driving lights turned on and when you press button does it light up bright can you feel heat in the window its cycled to stay on for 12 minutes i believe

here is the blower mod link
it is pretty straight forward to do i managed it and me and electrics dont get along that well :) :)

there is a link in the posts to a xls spreadsheet that Richard W has done.i unfortunately dont have a program to read that so Richard kindly sent me a pdf copy which if Richard has no objections to i can forward to your email will check with Richard first :) :)

this is a pic of the relay i used from maplins
Image

Colin

lexi
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Post by lexi »

Cheers Guys.

There is power across the elements at the back window when switched on. and screen clears quickly. Will check how long it stays on. The improvised fan switch blows full blast when flicked on.

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CitroJim
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Post by CitroJim »

lexi wrote: The improvised fan switch blows full blast when flicked on.
Gosh :shock: That's enough to blow you out of your seat Alex :lol:

I guess this switch has just been wired to be able to at least enable some refuge from the hurricane.

First thing you need to do is revert the wiring to the blower back to normal. You'll find there are two thick wires, a multi-plug and a couple of thin wires that go to the blower speed regulation module; the module itself lives within the blower housing under the fan motor.

If the blower blows full speed continuously whatever the slider setting, it's a fair bet the transistors in the blower module have failed short circuit. They can be replaced fairly easily but are a slightly unusual type. I can supply and fit if necessary.

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Post by lexi »

I got Blower unit out and have undone the two screws that hold the diecast module in. How do we split it now to get module/transistors out?

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Post by MikeT »

Time to plug in the electric drill and remove those rivets :lol: Buy or find some nuts and bolts for reassembly if you don't have a rivet gun.

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CitroJim
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Post by CitroJim »

lexi wrote:I got Blower unit out and have undone the two screws that hold the diecast module in. How do we split it now to get module/transistors out?
This Postwill show how Alex...

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Post by lexi »

Thanks Jim
I`ve read that up a few times mate. I don`t have the diecast item in the vice yet :o I`m truying to get the item out of the housing to drill out the rivets . Have undone the two screws but there is no room to pull transistor assembly out..............the fan drum is impeding it.......obviously I am missing something.

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Post by MikeT »

From memory; The big rubber damper it all sits in has some catch lugs which need to pressed in while the fan assembly is pulled out then you can access the rest.

lexi
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Post by lexi »

Where are they Mike ?. Everything looks like a catch lug to me on these assemblys :lol:

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Post by MikeT »

Sorry lexi, I've got an awful memory but I think I just pulled the fans/motor really hard from the housing and it came away, nothing broke. Then it reveals the lugs. :?

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Clogzz
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Post by Clogzz »

citrojim wrote:Clogzz … will be along soon
Oops ! :oops: Sorry, Jim !
Missed this topic, because of its title.

Alex, here are pictures showing how to get to the catches.

The blower flat-out with rocker switch could be a bodgie to bypass the speed slider, if it’s not the usual shorted transistors fault.
Recent story here:

http://www.frenchcarforum.co.uk/forum/v ... hp?t=23767

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