e36 numerous issues, mainly climate control, PLEASE HELP!

Hello all, Before you read this, please be aware that I have been researching about the climate control issue for about a year now, and have not had a resolution, because I believe my issue is quite unique in some way... Yes, I've tried going the route of the infamous climate control fix, where you can either solder the connection points for that specific capacitor, or replace it altogether. I took in the control unit to an electronics repair depot, and showed them the connection points and the capacitor of which to replace. To both his and my views, we didn't see the points as being worn off to even the slightest degree, and he told me the capacitor looks normal. The protective coating over all the connection points on the varous ICs, transistors, capacitors, etc., is still very much intact, and the connection points are all solid and not worn. So to my opinion, I strongly do NOT think the climate control unit is faulty. Read on to see why...

I own a 1999 BMW 323iS coupe w/ the 2.5L M52B25 engine. The following issues that I have occur when it is relatively warm to hot outside only:

- Electronic Climate Control fails to stay on; I believe that the default action for the car to do when it detects that there is no climate control hooked up, is to blow hot air towards the feet of the driver, and sometimes the passenger. Therefore, I think the climate control shuts off completely and the car then thinks there is no climate control installed, and defaults to blowing heat at the feet area.

- Power Steering fails to stay constantly pumping; the steering wheel will start to get really stiff to steer and almost feel like its going to lock up.

- When these two issues, especially the climate control not working, are happening, the car's dials/gauges (when the backlight is on) look dim compared to how they should be during a nightly drive.


The car can't keep a constant flow of electricity to my 30GB Zune when its plugged in through the cigarette lighter at any given time. It will charge the Zune for 3 seconds, then stop for 1 or 2 seconds, then charge again for 3 seconds, then stop for 1 or 2. I don't know if this is directly related to the above issues, but I thought it was worth mentioning. I plugged in my HTC Touch Fuze phone into the lighter, and it seems to have a steady charge being fed to it. I believe my Zune consumes/requires more power than my phone...

On two separate occasions in the last year, I was driving around 40 mph and the above 2 issues with climate control and power steering were actively happening, the car's gauges suddenly shut off and fell to their resting positions when I go about shutting the car off after driving. They shut off for just 1 second (like a fluctuation) and then kicked back into their normal positions (showing 40 mph and its associated RPM range). Remember, this happened only twice in the last year. It hasn't been a constant issue.

Finally, I checked the belts to see if they were cracked or about to snap. The belt that controls both the power steering and alternator was perfectly fine, no cracks, no tears, nothing. The other belt had two main cracks, and I replaced it. The issues above still persist after the replacement. I also checked to see if the wiring harness in the trunk lid was frayed (inside the rubber black jacket), but they were perfectly fine. I checked some wiring that led up to the climate control, and saw that they were fine.

When it is cold out, like in late fall into winter and then into the early spring, the main issues above never really occur. The power steering is normal, the climate control unit stays on and turns on within 1 minute of turning the car on, and maybe once per long drive (1 hour or more) will power off for a split second then stay on.

My guess is the issue is the alternator. I even checked all the fuses in the box that are related to these parts, and they are all fine. Why I think it is the alternator, is because, one, the alternator has a ram air duct that cools the alternator with incoming air when you're driving. Thus, since the incoming air during winter is very very cold, the alternator must be keeping itself under overheating temperatures, which is why it might be outputting enough voltage to keep these issues from happening. It doesn't explain why the power steering acts up, though. Two, my Zune can't even receive enough steady power to be kept charging while plugged into the cigarette lighter, which leads me to believe that maybe my alternator is being maxed out of its max. power output?

Also, when I start the car up, I can hear a faint high pitched squeel, which sort of reminds me of the sound when a serpentine belt is about to go out. But its very faint, doesn't sound nearly as bad. The sound goes away after the car has been either running at idle or if I've been driving for about 2 minutes. Does this sound relate to the alternator?

Overview: I checked the belts, they are good. Checked the fuses, they are good. Checked the wiring harness in the trunk lid, and some of the wiring from the center console up to the climate control, they are all intact and feel and look like the wires were just put in, like they are new! I expected to at least see some fraying in the trunk lid wiring harness.

1) Do you think the issue is with the alternator? I'm thinking about either replacing the alternator with an OEM version or upgrading it to a higher performance/output alternator, and having a mechanic put it in, because I don't have the parts or time to swap alternators.

2) If you think the issue is with the alternator, do you think its concerning that its not outputting enough voltage? I partly think I need to upgrade to a higher output voltage alternator to take care of the Zune charging issue, and at the same time it may fix the other issues, because to me it looks like the alternator is slowly dying, on its way out?

3) If you think its got to do with something else, what do you think it is? The only other thoughts I have would be, one, it could be somewhere that I haven't looked with the wiring. Perhaps there is melting/fraying somewhere else in the LONG trail of wiring that comes from the trunk all the way to the front of the car? Or perhaps there is a heat sensor in the engine bay that is causing certain parts to shut off (aka the climate control) if it detects a certain value in something, like temp or moisture level, I have no clue... just guessing.

What do you think? I know this post is quite long, but I hope to get this fixed once and for all, as I've tried many alternatives to trying to fix this issue. I took my car into Midas one time for a quick explanation (no charge), and they said that my A/C should be fine, and that it has something to do with the electronic climate control unit as a guess? Maybe the actual processor on the circuit board is defective or something.

Thanks for your time, patience, and thoughts on these issues! I'll tip $20 to whomever shouts out an explanation and it turns out to fix most, if not all these issues.
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