climate control , a/c

[StephenVA]

Guys

The 12V jump to the compressor is just that, a quick test to confirm operation of the clutch and that the compressor will spin, regardless of line pressure and system functionality. NEVER run a car more than a few mins. As was mentioned above, this test bypasses everything to prevent damage to the system. Ice forming, over pressure, over heating, compressor damage, etc.

[ants_oz]

Question - does the AC clutch take a 12v feed? It is not unusual at all for automotive components in modern vehicles to use voltages less than 12v. Applying 12v directly to a lower voltage component can render it a paperweight.

[bcredliner]

Originally Posted by StephenVA

bcredliner

Can you post the steps to test the aux fan using the IMPA or other software, so the OP can get the right procedures? A few screen shots will help here also.
I do not think some of our newer readers understand that the on-board computer has built tests that will fire up devices, switches, sensors, relays, etc. All of which need a computer to send the signal not a $50 OBDII generic code puller.

I don't use the BMW INPA-DIS software unless I have no other option. I use it so seldom I have to start the learning curve all over again and that is not fun for me.

I would start with the easy stuff. I would make sure all associated fuses are good. Then I would start the vehicle and see if the fan goes through the test, starting up, turning slowly and then shutting off. If it doesn't I would ask someone how to use the software just as you have or go to the forum dedicated to using the software package.

More likely, I would pull the bumper and remove the fan as the most probable cause and bench test it to make sure it was the fan rather than a problem upstream.

[bcredliner]

Originally Posted by ants_oz

Question - does the AC clutch take a 12v feed? It is not unusual at all for automotive components in modern vehicles to use voltages less than 12v. Applying 12v directly to a lower voltage component can render it a paperweight.

No need to test the clutch you can see and hear if it engages when you turn on the air.

[ants_oz]

Originally Posted by bcredliner

No need to test the clutch you can see and hear if it engages when you turn on the air.

While that is true, my point is somewhat different - there are people talking about applying 12v directly to the clutch to check whether or not it WILL engage.

If the clutch is not engaging, is it that the clutch is stuffed, or is it that there is another part of the system preventing it from engaging?

THAT is what I took from the discussion around applying 12v to it.

[bcredliner]

Originally Posted by trader4

If the clutch doesn't engage when you turn on the air, it doesn't
tell you anything about the clutch. It could be the clutch, or it
could be the clutch isn't getting 12V, for a whole bunch of reasons.
Ultimately you may have good reason to test it.

I was not addressing anything other than before I would do any tests, I would look and see if it is engaging when the air is turned on. Testing of any sort would be prudent after a visual and ear test confirms the clutch is not engaging. Obviously, if it is not it could be due to more than one cause.

[bcredliner]

Originally Posted by ants_oz

While that is true, my point is somewhat different - there are people talking about applying 12v directly to the clutch to check whether or not it WILL engage.

If the clutch is not engaging, is it that the clutch is stuffed, or is it that there is another part of the system preventing it from engaging?

THAT is what I took from the discussion around applying 12v to it.

I see your point. I would consider doing that unless I could test for voltage on related wires with air on and air off.

[upallnight]

Originally Posted by trader4

The point was, you posted this:

"In the good old days you would just jump 12V to the compressor to confirm its ability to function. Now days all parts up stream must be working before system tests will complete"

So, again, shade tree or whatever you want to call that test that you
could do in the past, AFAIK you can still do it with the X5 today. Your
statement implies that it can't be done.

"From you previous posts I see that you are taking my advice about not fixing stuffs that breaks on your X"

No idea what that refers to or means.

Nope, my statement and explanation implies that this should only be done only as a test. It should not be considered a FIX or a work around to get back AC in the car without fixing the real problem.

Let See my statement was Fix it right or don't fix it.
You have a broken DISA valve that you know of, but didn't fix but still drive the X.
You have a broken Aux Fan that you know of, but didn't fix but still drive the X.

Glad I'm no longer in the market for a X. With owners that maintain cars like you I can see why there are so many noobs coming on this forum after purchasing a use X.

[upallnight]

Originally Posted by trader4

Attempt at diversion detected. Attempt at diversion rejected.
Your statement that I responded to wasn't the above, it
was this:

"In the good old days you would just jump 12V to the compressor to confirm its ability to function. Now days all parts up stream must be working before system tests will complete."

So, stop lying. And all I said in response to that was that AFAIK,
you can still just jump 12V to the compressor as a test, just like
you could in the past. I thought it important to clarify, for people
like the OP who are seeking help in how to diagnose, how the AC
system works, etc. I didn't get nasty, didn't take shots at you.

And now you want to take cheap shots at me? Owners that maintain
cars like me? YOU don't even understand how the AC clutch works
with the rest of the system, as evidenced by the above. And when
you post something here that's incorrect, when someone points
that out so that others won't be mislead, instead of just correcting
what you said, you deny and try to divert. And now
you want to drag DISA in here? Yeah, I've driven it for months
with the DISA inoperative because I understand what the DISA
does and doesn't do. I made that call. Same thing with the aux
fan. It's the third fan in the car and I'm rather tired of paying
$450 for a new piece of junk one. It's a terrible idea, putting
electronic components, unprotected, in one of the worst environments
possible. So, in the summer I don't have cool air for a minute
when stopped at a light. For me, that's an acceptable tradeoff.
And maybe the X is the only car you have, you use it to haul
your boss around in or you're deeply in love with it. In my case,
the X is a seconday service vehicle I use primarily when I need to
haul something, to go to ski resorts, etc. It's only worth a few
thousand bucks, I'm not too keen on pouring money into a high
mileage, 13 year old vehicle that's only worth a few thousand
bucks, for non-essential items.

Further, what I learned from the above directly contradicts what
others here have claimed. For example, some have claimed that
the AC will not run at all without an operating fan. I think 2 years
experience that proves that wrong is useful information for
anyone trying to understand how the system really works.
Same thing with DISA. It's useful info, because some people
thing that without a functioning DISA, the car won't run or
will run poorly. Apparently that kind of useful information
upsets some people here, like you.

Like I've told others here, your car, your money, your choices.

But just man up to what you actually posted, instead of taking
cheap shots and starting a divisive argument.

Go back and read post 21 and 24.

As for the post that you responded to I didn't post it.

http://www.xoutpost.com/1042461-post23.html

Why don't you post picture of your broken aux fan(s)? I posted pic of my broken aux fan. If your failure mode was the same as mine then I don't know why your ac is still working.

Not a cheap shot, I stated either fix the X correctly or don't fix it. Obviously you chose to not fix the X. That is your decision.

So when you decided to get rid of the X and sell it to a new X owner are you going to replace the DISA valve and Aux Fan? Probably not and probably won't tell the new owner about these two problems. New owner will search the internet and ask why his X lack power in the mid range and why his ac only blow cold air when it is moving but warm air when it is stationary.

[upallnight]

Originally Posted by trader4

Yes, I see now that you didn't make the post that I attributed to you, so
I apologize for that. You could have simply pointed that out a couple
posts ago, when I first replied, instead of starting personal attacks.

As to posting pictures, the fan is in the car, I'm not going to tear it
out just to post pics. And pics aren't likely to do much to solve
the question of what exactly failed.

"So when you decided to get rid of the X and sell it to a new X owner are you going to replace the DISA valve and Aux Fan? Probably not and probably won't tell the new owner about these two problems. "

And there you go again, with more totally unsupported personal attacks.
Is that what this forum is about now? As to lacking power in the
mid-range, you're once again in over your head. I've seen absolutely
no noticeable difference in performance with the DISA working or
disabled. I have seen others here report the same thing. Are you
going to personally attack them too?

What about the other fan that you have already spent 450 bucks to replace?