No heating/Air conditioning - Baffled

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Re: No heating/Air conditioning - Baffled

Post by GiveMeABreak »

Ok, I'll really need the full codes Kenny as there are a few of them with the same prefix. These should be stored in the log (top left corner menu of Diagbox), so you should be able to get them from there - or re-run the Global and let me have the codes. I might be able to throw some more light on it if I have those. :)

Some of the backup modes can give the appearance of a fault that doesn't exist, because the backup modes of some of the functions can result in limited function of some features (like the manual fan control having no effect apart from auto mode). As Auto mode often remains at a low fan setting, this could be what you are experiencing - so important to see what it is not happy about.
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Re: No heating/Air conditioning - Baffled

Post by admiral51 »

Kenny if i am correct by bridging the 2 wires in the thread i linked to will it actually put 12v directly to the blower motor. This should do the same thing as removing the blower itself and applying 12v directly to it.
I am not very tech savvy but looking at Marcs post above to me it shows an increase of voltage ( to me power ) on a linear scale but if the blower is a little sticky then it starts buts needs more power to get it moving and the blower module regulates it and will not allow extra power ( volts) until next step is completed then module is working it is the blower motor that needs a jump start ?
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Re: No heating/Air conditioning - Baffled

Post by GiveMeABreak »

I think Kenny said it was working on the lowest setting Colin - so it isn't likely to be the blower as it probably wouldn't get to first base if the bearings were sticking. But in this case where we have fault codes, the system might have gone into a backup mode. Once I know the specific codes I can confirm this and hopefully which area is causing the problem.
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Re: No heating/Air conditioning - Baffled

Post by KennyW »

Marc and Colin,

My motor is blowing but I don't know exactly what setting it is. I can only judge this by the sound and it appears to be closer to the lower settings rather than higher.

My reason to remove blower was to check the innerds but after reading your post. I will try the jump method.

Kenny
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Re: No heating/Air conditioning - Baffled

Post by GiveMeABreak »

All that will tell you is that the blower motor itself is operating properly - if it goes to full power which it will if jumped directly of course. It's everything prior to that which we need to determine as best as possible where the fault is. But at least jumping it directly will eliminate a dodgy blower motor.
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Re: No heating/Air conditioning - Baffled

Post by KennyW »

Jumped to blower motor and it worked on full power.

Going to check diagbox and fault code. Also will inspect to see if blower motor can be removed as indicated.

Will get back later today

Kenny
C5 x7 2.0 HDi 160 hp Estate exclusive, moved on.
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
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Re: No heating/Air conditioning - Baffled

Post by GiveMeABreak »

So the actual blower motor is working fine then Kenny - do you need to remove it in this case? I would now be looking at the blower control module itself again and the signals / wiring to it. But if you can get those fault codes it may be significant.
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Re: No heating/Air conditioning - Baffled

Post by KennyW »

Marc,

fault code F72F air blower motor faulty.

I believe it is the same problem PaulR, Colin and Greg have spoken about in

viewtopic.php?p=597285#p597285

because the car was laid up while I fixed the Rear suspension pipe.

I'm going to remove the blower but will wait for better weather and lubricate same meantime I will use the jump method to get the blower working meantime but require some heavier wire due the amps involved.

Kenny
C5 x7 2.0 HDi 160 hp Estate exclusive, moved on.
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
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Re: No heating/Air conditioning - Baffled

Post by GiveMeABreak »

Ok, that's great - here's the descriptor for that fault, so this should give you all the areas to check.
Fault Code: F72F Blower copy voltage fault: Not characterised

Description of Fault:The blower is supplied between 0 and 12V.
Variation of the blower consists of a variation of the earth.
The blower control module varies the earth as a function of the power required. This power is taken from the supply voltage of the blower, the result being called copy voltage. This voltage is compared with the theoretical value, if the value is not correct, then the fault code appears.

Conditions for Fault to clear: Blower copy voltage: NORMAL

Downgrade Modes whilst Fault is active:

Symptoms: Malfunctioning of the blowers

Suspect Areas:Fuses, Electrical harness, Earth point MC32, Air blower motor, Air blower control module, Air conditioning ECU
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Re: No heating/Air conditioning - Baffled

Post by KennyW »

Thanks Marc,
C5 x7 2.0 HDi 160 hp Estate exclusive, moved on.
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
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Re: No heating/Air conditioning - Baffled

Post by admiral51 »

Kenny i assume that when you put the plug back on the blower didnt work after the bridge trick ?
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Re: No heating/Air conditioning - Baffled

Post by KennyW »

Colin,

It works at only 1 speed but I was thinking a slightly longer run at high speed might loosen it hence getting suitable wire and connectors.

But the problem will return so will require the removal of blower. I had a look at the removal and it maybe possible to remove through the gap.
The following problems were encountered:
1. You can't see the tab which has to be pressed to release the blower.
2. You can't see the 2 pin wiring connector.
3. It is difficult to grip the blower with your hand.

By removing the glove box and lid will increase access and sight.

Also this operation is weather dependent for me no access to shelter at the moment

Kenny
C5 x7 2.0 HDi 160 hp Estate exclusive, moved on.
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
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Re: No heating/Air conditioning - Baffled

Post by admiral51 »

I have to as always admit i was probably wrong and young Marc is correct as normal.
When i did it on my old one the blower worked as it should once the plug was put back, touch wood not heard a peep about it since.
As you have changed the Control Module and still got no improvement then there is something else going on, the blower has been confirmed to work with the bridge trick.
Stupid idea but................
If the Blower Motor was a bit sticky and the old Control Module was good then the fault was with the Blower Motor being sticky after being sat for a while.
Now that the Blower Motor is working at full speed, have you tried putting the old Control Module back in to see if there is any change as the new Control Module maybe duff ?

Just thinking out loud as usual but i cannot recall you saying you had fault codes until you put the new Control Module in

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Re: No heating/Air conditioning - Baffled

Post by KennyW »

Colin,

I didn't check for codes in the heat/vent ecu until later ie 'new' module. I will try the old module as I'm now getting quite adept at removal and refitting just like Paul. :-D

Kenny
C5 x7 2.0 HDi 160 hp Estate exclusive, moved on.
Xantia 2.0 Hdi 90hp 1999 only 189,000 and rising!!!!!!! Moved on to a new home
C3 1.4 petrol (SWMBO)
Xantia TD 1.9 Mk 2 Estate LX 1998 model over 210,000 miles now and still rising!!!!!!!!!!!!! now deceased 17/12/2010.
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Re: No heating/Air conditioning - Baffled

Post by Paul-R »

I have the scars on the back of my hand to prove it!
As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

"Trying is the first step towards failure" ~ Homer J Simpson​