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Air con

Posted: Thu Jul 02, 2015 11:25 am
by Micevo
Hello

Where to begin!
Got the car about a week ago so just learning my way around it, first problem is aircon not working, had it regased as it was empty, now still not working, compressor clutch is engaging when switched on and disengages when turned off, so presume that's ok,

Aux / pusher fan not coming on, I've put a volt test on the plug and get 12.6ish V from red wire, thin wire 0.003 when not turned on, an about 3v when aircon turned on, brown wire no volts so presume earth?
Does this fan have to be on for aircon to work? Eg no fan no aircon or will aircon still work without fan and I need to look else where?
All ideas will be greatly appreciated ,

Other niggles I have with it :(
Passenger window sticks down,  need to replace a plastic thingy ordered
Headlight washer not working , new pump ordered just arrived will do today
Pixels in radio mid not good looking into sorting that, might just get a ribbon or send it away
Oh yea parking sensors what a pain got front drivers side not working so none work , is there any way of disabling just the front sensors?

Thanks

Re: Air con

Posted: Thu Jul 02, 2015 1:48 pm
by lezmtaylor
Just a thought,
Have you turned the knobs on centre vent to Blue markings, it won't blow cold if you haven't.
Sanj , or someone more qualified than me will be along shortly to advise.
Regards,
Lez

Re: Air con

Posted: Thu Jul 02, 2015 2:07 pm
by Micevo
Yes they are on the blue,

Cheers

Re: Air con

Posted: Thu Jul 02, 2015 11:05 pm
by X5-D-Sport
I have exactly the same problem.....
Everything works... but the fan simply WILL NOT TURN.

I even connected my car to another vehicles fan to whlebit was still in the other vehicle... and it proved that the signal to power up my fan simply wasnt happening... even bought another fan motor.... still no good...

And the information just stopped there....

It turns out that this is not an uncommon problem, but no one seems to have the answer....
Where does the bloody signal come from ? And why does it stop ?

Conclusion..... WITCH-CRAFT  !!

So yesterday, I tore the whole bloody thing out of the vehicle, enjoyed beating the crap out of it ....
& got an electric 17" fan off ebay for £30 and will wire it to the ignition live via a relay tomorrow when it arrives.

Some things on these vehicles are logical.... others are simply a pain in the crack !!

Re: Air con

Posted: Fri Jul 03, 2015 8:16 am
by Micevo
Yea I believe there might be a resistor or something along those lines around the front wheel arch which might have something to do with signal,

Does your aircon work without fan? Don't wanna get another aux fan if it don't fix problem if you see what I mean

Cheers

Re: Air con

Posted: Fri Jul 03, 2015 9:42 am
by X5-D-Sport
Hi MicEvo,

My AC works fine as long as youre doing 40mph+ to get the air thru the intercooler on the front of the car...

If the AC pump clutch is working & the knobs n dials are inbthe right place it all works fine...
The centre dash knob needs to either be centred or set to cold, and the digital temps at 16'...

If it still doesnt work, then yours may need re-gassing....
I bought a bottle of gas & a gage with adapter for about £45 all up & did mine with good results.

I was surprised how low the gas level can go & it still works well...

Tell me about this resistor in the wheel arch ?
This is new to me.... didnt know it existed... where is it ??

Re: Air con

Posted: Fri Jul 03, 2015 10:53 am
by Micevo
Think there's a resister or regulator  thingy under the wheel arch something to do with a fast and low speed of pusher/ aux fan, sure I read it on an American site like bimmer something or other,

On mine might have to look at other things then!!!

Cheers

Re: Air con

Posted: Fri Jul 03, 2015 4:17 pm
by fenj66
In reply to an earlier query.  Yes you can disable the front parking sensors so just the back will work.as i have done. But it needs to be coded with a scanner or similar.

Re: Air con

Posted: Fri Jul 03, 2015 8:54 pm
by TimX5
My air con works fine but the pusher fan does not work but still cold air in the cabin when stood still although it's maybe not as cold as when driving  , another thing is that when accelerating away with the air con on the engine seems to be abit noisier.

Re: Air con

Posted: Sat Jul 04, 2015 9:24 am
by X5-D-Sport
Re pusher fan not working....
I have a spare motor unit that Im going to experiment with later today.

It turns out that the signal wire to the fan feeds a PWM 5 volt square wave signal...
As the frequency changes, the fan motor decodes it to adjust the rotation speed...
The interesting bit is that.... maximum signal will result in a solid 5volt posative edge signal...
So, I bought a variable voltage & current limited power supply from Maplins for £100 & going to play later.

The current can be limited to say 50mA which will prevent damage to the fan electronics, and step the voltage up from 3 to 5 volts until the fan responds...

If it does...... To re- create a 5volt max signal,  I also bought a voltage regulator chip, some ceramic 0.1uf capacitors, a 250uf electrolytic cap & a couple of 10k resistors as current limiters & a matchbox sized case....
As this 5v regulator could potentially activate the fan as posing as a maximum speed signal feed...

We will see what happens....

Re: Air con

Posted: Sat Jul 04, 2015 9:27 am
by Micevo
Thanks for all your replies think we might have got to bottom of problem now, just testing it for leaks today then going to regas again , yea my pusher fan doesn't work so new one needed, put the engine light on twice now when stood in traffic,
Parking sensors: had it on scanner but couldn't find where to disable the front one so think I might just put a new one in, as bumper coming off when I replace fan,
Window replacement parts on order,
Washers done,
Hopefully by next weekend all done  :) till the next thing....  Oh yea got do fluids then that's it!!!

Something which might be useful for some.... Pixels in radio MID found this guy who fixed it for £40 he also does the dash board ones,  if interested I can send you his email address , dropped mine to him and had it back in couple of hours..

Cheers

Re: Air con

Posted: Tue Jul 07, 2015 6:57 pm
by TimX5
My pusher fan isn't working so I checked the power and everything ok then took it to a friend who plugged it into the diagnostics to power up the fan and it's definitely knackered £415 + vat of bmw so looks like it's eskip for a second hand one.

Re: Air con

Posted: Tue Jul 07, 2015 10:37 pm
by X5Sport
Did you send me a PM?  It showed in my email, but not on this site!!  The answer is yes it was with the pusher fan running at full speed.

Noisy a/c could be a compressor clutch fault, or a bad compressor I would guess, and assuming the gas pressure is correct?

Re: Air con

Posted: Tue Jul 07, 2015 10:54 pm
by TimX5
[quote="X5Sport"]
Did you send me a PM?  It showed in my email, but not on this site!!  The answer is yes it was with the pusher fan running at full speed.

Noisy a/c could be a compressor clutch fault, or a bad compressor I would guess, and assuming the gas pressure is correct?
[/quote]

Yes I sent you pm , air con works fine while driving,  pusher fan definitely knackered  but the air con pump seems noisy when accelerating away but when stood still and reving the engine with the air con on it seems fine.

Re: Air con

Posted: Wed Jul 08, 2015 6:34 pm
by X5Sport
Shouldn't make any difference in that case, so could be something else though quite what is a puzzle.