hvac control inop
 

Hey everyone, brand new member. My wife was driving her 02 X5 when she heard a pop from the dash and a few seconds later the a/c was blowing hot. Looking down at the hvac control, she noticed it was not lit up and the buttons were unresponsive, however the fan was still blowing on high. Even after turning off the vehicle the fan continued to blow. Nothing short of disconnecting the battery had any affect on the fan. When the battery is reconnected, the fan responds just like at start up where it starts blowing slowly and ramps up to high but, still no power on control unit. New to BMW, love the vehicle, but need to keep the wife cool. Thanks, Craig

Welcome to the forum.

I'm not an expert on electronics, but have you checked the fuses located inside the glove box? Sounds like a blown fuse.

Welcome. Can you do us all a favor and place you car info in your signature. Like mine for example. Helps us identify your car on the fly.

As far as your problem, check the fuses in the glove box. If all good there, search for FSR. Use the search this forum option. You should find similarities to your issue.

Checked all fuses in glove box and on right side panel of cargo area. Used test light, hot on both sides of fuse. Are there any other fuse boxes to check? Will search FSR.

Read a few of the FSR posts but not sure that's my problem. Most of those had fan issues of one sort or another, but had power at the control unit. My problem is no power at the hvac control unit. I can't find a specific fuse labeled as such and I haven't yet pulled the unit out. Any other suggestions or am I missing something concerning the FSR.

No I think you are correct. FSR is not your issue. Yea pull that bad boy out and see if anything is unplugged or something. Really strange.

OK, pulled out control head from dash. Had a 3 wire harness with one hot wire, a black multiwire(12) with no hot wires, a blue multiwire(26) with three hot wires and a small black 3 wire harness that looked insignificant with no hot wires. Disconnecting the blue harness made the fan stop blowing.....I'm thinking control head???

I'd double check fuse #48 (AC and heating) inside the glove box. Pull it out to check/test. Skip if already done.

After reading through the trouble shooting on the Bentley X5 Service Manual (not much help), I agree with you--bad Climate control panel.

From RealOem: RealOEM.com * Diagram Selection

Is there a way for you take the control panel to have it tested?

Even if you replace it with a new one, am I wondering if the root cause of the "pop" was from somewhere else. Will it reproduce the same "pop" and kill the new control panel? It's an expensive new part to test on uncertain electrical system.

Maybe someone will chime in to help explain the signs and symptoms and causes for a blown climate control panel.

Please keep us updated. This is a very interesting case. Thanks.

I am having a same problem on 2002 x5 3.0.

I was washing the car one day and seem like i shorted out some wires, It stays on for about 20 mins and returns when i start the car or open the door.

It is really a tough since it blow hot air during hot summer days.

Will try to pull the fuse out (48), but if some has had a fix, a post will be appreciated.

also all lights on the control panel is off. no temp and button do not function.

Hi, This is my first post. I just went through this. I have a E53 3.0

Nothing short of pulling the fuse for the fan will stop the fan. The air is not cold and is blowing full blast. The control panel fails to function. In fact there is no light at all at the panel.

In the end had to buy a used control panel to replace. Take note that not all the panels are compatible. Best try to get one with the exact part no. I had to go through 3 of them before getting the right one with the same part no.

DS. I think just based on your irratic fan operation, your FSR needs to be fixed or replaced. There is actually a DIY for fixing it on here. Just search for that. Or buy a new one from dealer. I prefer getting in touch with Craig at Bloomfield BMW. No one comes near his pricing.

Fixing the FSR requires some soldering skills.

HVAC Control Inop - Fan Hot Powered!
 

Thanks for the reply SlickGT1.

I'm not against going after a bad fan, but only for just cause.

Do you have experiential reason to believe that my fan could be bad if:

1. It is continuously blowing at a high speed?
2. The AC control panel was intermittent for 20 minutes before going dead?
3. During that time the vent valves and temperature controls were ineffective?
4. The fan stays on and maintains its speed even after the key is removed from the ignition and car locked?

If you do, I'll start suspecting the fan. - DS

Shit stupid auto correct. Sorry. FSR. Not fan. Replies the FSR. Going to edit that post. Sorry, iPhone ownage.

HVAC Control Inop - Fan Hot Powered!
 

Just received my Meyle (Germany . . . part made in PRC!) replacement FSR from Bav Auto.

I had not run the truck for 3 days. Put in the new FSR, reattached the blue harness to the back of the IHKA and NO HOT POWER to the blower. So far so good.

Started the truck and everything began to work fine. The IHKA was all lit up and controlled the blower, vents, and with the temp set to 60, cold air was blowing out of the vents front and back. The engine was still cool so I checked to see that the aux fan was running and it was. I wanted to ensure that the a/c was turning it on and not a water temp switch.

THEN . . . within 10 minutes, the IHKA began to flicker slightly and eventually die again. I turned the vehicle off and removed the key. All was quiet and then I heard the blower begin to spin and slowly spool up to full speed. Same deal all over again. I disconnected the blue IHKA harness to stop the blower once again.

Disconnecting the black harness will also stop the blower. Whenever I reconnect the harnesses, the blower begins to spool up to full speed again with or without the key in the ignition.

Ideas?

Ok now that is some strange shit. What would cause the blower to go full blast with a good FSR? I have to think.

HVAC Control Inop - Fan Hot Powered!
 

Took her in yesterday for dealer diagnosis. Bad controller.

Paid $520.30 for a new controller and so far (~ 3 hours of use) so good.

The original FSR that I replaced is probably still good. Will keep that in the SAV as a spare if my replacement FSR craps out.

Anyone need a replacement front panel for their IHKA controller?

Damn, well now we know this can do it too.

Finally fixed!
 

After much delay, the hvac control is repaired. To make a long story short, the control head needed to be replaced. Found Hi-Tech Electronic Services in CA (800)580-3376 who initially thought they could repair my existing unit. However circuit board was on backorder and after several weeks found he could order an exchange for couple hundred dollars which we did. Dealer wanted $500 + for new one. One word of caution that most may know, there are at least two different heads for this and similar year models. The difference is the number of pins in the black connector. Be sure you count them and let Hi-Tech know which you need. That would have saved me a couple of weeks back and forth. Thanks to all who contributed.