Thought it was the blower, but IHKA control panel doesn't work now, confused

[Georgeous]

For a long while, I was in the classic situation where the fan would blow cold air without any problem except for when it would seem like the climate control would reset by itself and the control panel would indicate that the temperature was 92 instead of 60.

Then the fan would not turn on when I would start the car but after a random amount of time, usually a few minutes, it would turn on by itself.

Finally, the fan stopped turning on at all and I thought that the fan or the resistor or maybe both had finally had it and I got over the sticker shock and ordered both parts tonight.

Now I am thinking I should quickly cancel that order because tonight the control panel stopped turning on at all. Before, even when the fan wasn't working, it would still display the temperatures and even let me turn on the AC so that when I was going at freeway speeds air conditioned air would blow in through the vents.

Tonight, for the first time, it didn't even display the temperatures and it didn't turn on the rear window defroster when I pressed the button, which makes me think that it's not fan related. For that matter, none of the other functions seem to work. I am suspecting that it was the control panel all along.

So what am I supposed to do to verify that it is the control panel? Also, does there exist a repair service for these modules that anyone can recommend (ideally in southern california)? I just took a quick glance at Ebay and got sticker traumatized so I am hoping that a repair can be cheaper.

Finally, one more question, is there an easy way to verify the month/year my car was made? I keep being confused whenever I go into my etk because of this.

Thank you in advance, without functional ventilation this car is practically useless during California summer daytime.

[Mayorchuck]

Check Fuse 20 as it power the IHKA.

http://forums.bimmerforums.com/forum/showthread.php?2003822-Blower-motor-info





Your build date in on the plate inside the door jam.

[Georgeous]

Ah, thank you, I found the build date, 8/96, thank you, it's good to have peace of mind that I am not picking out the wrong parts.

Thank you for the link, I checked the fuse, alas, it's never the fuse.

The weird thing is, when I turned on the car just now, the control panel activated. I could turn on the rear window defroster and when I played with the fan settings I could hear short vrring sounds like something was attempting to be adjusted. Now I'm really confused and suspecting that both the blower/resistor are damaged AND the control panel is on the fritz as separate issues. *sigh*

Just out of curioisity, how is the control panel removed? I don't see any obvious way to take it out, does it need a pry tool or something?

[Mayorchuck]

Never tried this but going to this weekend to change mine:

http://www.laczik.org/BMW/repair/E38_AC/E38_AC.html

Otherwise:

http://www.bimmerboard.com/forums/posts/428942/

[racer2086]

May be worth pulling the battery for this one as an easy last ditch effort. The IHKA may be glitched up or something.

Other than that, you can get another used IHKA (A/C panel), but it may need to be coded to the car unless you get one from a similar build date vehicle.

If you had the computer software, you could run tests on the system to identify what's wrong.

[Georgeous]

No, I'm afraid I don't have the computer software, but do there exist any repair services for these consoles? Replacements are just so steep...

[BobsBimmer]

I have a used control panel. $75.00 shipped if you find you need one...

[Georgeous]

Thank you for the offer but I don't think my car is compatible. I have the kind that has the two little temperature displays and two wheels for controlling fan speed.

[Mayorchuck]

It is compatible but it may or may not need to be coded. The newer units are backwards compatible and some have had success with the 'REST' ones like the one above without coding. Might be worth a shot. What I often offer in this case is to sell and ship the part. If it doesn't work, buyer pays to ship it back and I refund the money minus my shipping cost. Just an idea.

[BobsBimmer]

It is compatible but it may or may not need to be coded. The newer units are backwards compatible and some have had success with the 'REST' ones like the one above without coding. Might be worth a shot. What I often offer in this case is to sell and ship the part. If it doesn't work, buyer pays to ship it back and I refund the money minus my shipping cost. Just an idea.

I would be willing to do that for a member!

[Georgeous]

So, besides the coding issue, it is otherwise backwards compatible? I might just have to consider that but I don't like the thought of throwing away otherwise perfectly good parts just because of a couple of cold solder joints or leaky capacitor. I'll poke around if I can find a repair service.

[Mayorchuck]

Correct. Just noticed you said you have a 08/96 model. Don't think I have seen thumbwheels that late although I think Q said they went until thru the early '97 models. I have a 01/96 model with the IHKA Bob has. Also noticed you info says you have an E39. Setup would be the same but do you have a e38 7 series?

Can't hurt to look at the motherboard for a bad solder joint.

[Georgeous]

Sorry, I have tried to change my car multiple times but yes, I own a 97 740i 8/96

[Georgeous]

So, one guy I was writing to suggested that my best option was just to simply buy an upgraded controller but before I make that leap, how do I know it will be compatible with my 8/96 740i? Is there a chart or something?

http://www.ebay.com/itm/151055568082

[Mayorchuck]

That has the MAX button and guaranteed to have to be coded to your car. Bob's is the next step up from your current IHKA and may or may not need to be coded. I just put my replacement in tonight. Both were the REST model but I still had to code it to get all the features to work, mainly the compressor signal. As you can see, the numbers are just one off.




Note the dust accumulation in the small fan intake. Did not notice that from a sitting position. Clean them suckers out!



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Strange that when you try to pull up the 8379111 in realoem, it says it's not found. What part number is on yours Bob?

[IcemanBHE]

Take the cover off and blow the dust out of the fan wheel behind those vents.

[Georgeous]

How do I remove this unit? I see no obvious way to do that.

[Mayorchuck]

See the links I posted in Post #4. What I did today was remove the PDC switch below the IHKA. I also remove the coin holder above the MID. This allowed me to push on both the top and bottom of the unit. I could not get enough force to push it out from just the bottom. You can see the clips that hold it in the first pic. There are two on each side. They just bend down as you push it out. Mine were stiff. Otherwise you need to follow the instructions in the link above.

- - - Updated - - -

Take the cover off and blow the dust out of the fan wheel behind those vents.

I was really surprised how clogged it was. I took this pic after I blew into it once. With all the gravel roads and farm fields around me, best check the filters again as well. I am going to take mine apart to see if I can figure out the LED issue.

[BobsBimmer]

the part number on mine is 6411 8 379 112

[Mayorchuck]

That's what my original one was. It's also what's listed on realoem for our models thru 99 I believe. Probably your best shot at one that may not need to be coded Georgeous.