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1st time bmw owner & post. need help

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Hello everyone...I bought a 92 525i 3 weeks ago & its runs great but seems to have many electrical gremlins some of switch i have tackled or in the process of tackling. right now i have fairly serious battery drain issue (fully charged battery is dead after 2 days of not using it) the drivers window only goes up about 4 inches at a time then i have to push it again & again to get it all the way up but goes down no problem & tracks fine, drivers side rear window goes down ok i guess but when i go to put it up it goes all sideways & need to be manually adjusted multiple times to get it all the way up & every time i hit any window/sunroof switch i hear a single click from under the backseat is this a relay or something else? im hoping i solved the after market radio issue....wired to harness & it powered up fine (FM was a little sporadic & AM seems nonexistent) but cd played skipped all that good stuff but had no sound what so ever but after reading another thread i think i found my error...the blue/white wire to blue wire or at least i hope thats it. I have been reading quite a bit here at bimmerfest & find this to be the most helpful site with knowledgeable people so i hope u all can help me with my issues as i know of now & as they arise. oh yea & when i go to crank up the heat or A/C the fan only blows on highest setting or lowest setting could this be the switch or the fan itself or something else?
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sry i was a little all over the place there, but i am at a loss & not the most mechanically inclined...any insight or thoughts would be greatly appreciated
Regarding the dead battery issue, here are some of my recent fixes chasing that gremlin:

1) Found main power wire from alternator to be rubbing on the steel part of the power steering suction line going from reservoir to pump. The rubbed through the cable insulation causing a direct short, and for me, pretty much a small fire on the oil lines. This was fixed using heat shrink tubing, heat tape, and a spark wire heat sock.

2) Replaced voltage regulator, voltage still dropped when running to below 12v when raining or under-sprayed at the car wash. Point here do OBC4 test #9 and watch your voltage. How to use OBC4 : UnofficialBMW.com & M5Board

3) Inevitably replaced alternator. Discovered front bearing to be going out on alternator. I sprayed a little, I mean tiny, squirt of water into the front of the alternator and it made all kinds of racket. Not to mention took running voltage from 13.9-14.1v down to 11.9-12.1 volts. So I knew at that point I had a serious charge issue, but the most concerning part for me was reading about the rectifier in the alternator. I read somewhere that a rectifier can "partially" fail. Meaning one or more of the diodes can begin to leak. And it was described as taking a few days to drain to a no start situation.

Keep in mind, mine is a V8, so the wire issue is not likely to pertain to your car. The alternator stuff is the most important part of my rambling.
Regarding your front window, provided it's not binding would seem to me to have faulty limit switch or window control module. Someone else here may have more direct knowledge of that. The rear window, sounds like ONE OF THESE is broken or disconnected. Hopefully it isn't an internal failure of the REGULATOR, and I'd doubt it is.

The clicking, yes a relay.
The blower motor speed issue is most likely THIS DODAD aka "sword" aka "Fan Limit Switch."
My 95 had this same problem. there was a trailer wiring adapter tucked in by the factory amp that was pulling constant power, I have no idea why it was there, there is no to hitch.

Removed the wiring harness and the drain was gone.
right now i have fairly serious battery drain issue (fully charged battery is dead after 2 days of not using it)
thank u Einstein i see u live up your name. doing the OBC test is that going to display on the dash OBC or the 1 i enter the codes into? my dash OBC constantly displays something about brake linings with a plus (& something else that i cant think of off hand & go figure the battery is dead right now so i cant just turn the key & see atm) however the guy i bought it from said he recently put new ceramic brakes on it so idk why that is being displayed unless it was never reset & if that is the case how do i reset it? anyway back to the point is that brake linings display that i can not get rid of going to interfere with with the test display? & thank u so much for the links to rear window parts, i have been having a hard time finding the right words to search for them. & which relay could that be clicking in the back, what is its function & why is it clicking...a short, its gone/going bad......

thanks for your input barf bag, i have been reading about the factory amp & have read it is behind the back seat in the drivers side corner is my memory serves me right but i cant figure out to how to remove the back part of the seat, the owners manual that came with the car seems to be full of incorrect info, it says my backseat should fold forward & have split rear seat that fold down for extra storage for the trunk & also says my battery is under the hood which of course its not, the rear seat pulls out completely & the battery is under the seat & the back part doesnt want to move at all, so how can i access this area?
First, when you replace the brake pads, you also have to replace the wear sensor so that warning goes away.
Some E34's have the battery under the hood, most do not.
The amp is in the trunk, it is on the driver side wall under the covering, just truth release screws and pull the fabric out a bit just like you would if you were changing a tail light bulb.


The warnings will not interfere since they display on the computer you enter the code into.
thanks zombie i thought i read the amp was behind the seat but at least i was in the right general area...lol...& yea i read about the sensors for the brakes, i have read about people just grounding out the sensors to get rid of the display. does it cause any kind of problems doing that? i mean it doesnt take a rocket scientist to figure out when u need new brakes...lol btw thanks again zombie i think it was u that said something about the blue/white wire to the blue wire with the radio swap in a diff thread i read, i finally have tunes again =) now to just figure out a way to make it sound a little better, i dont suppose theres a way to fit some 6x9s in the back for better bass is there? i have some decent composite 6inch speakers would i be able to squeeze them in the back? oh yea 1 more thing is there any videos out there showing how to remove the door skins (passenger front & driver rear) from a 92 525i or whatever models that has the same set up or can anyone give good detailed instructions or share a link for a car idiot? lol
About the linings sensors, note that replacement pads for this car (well none that I've seen) do not have the squeeler tab. So you would either have to monitor your fluid, or wait till they're grindin. The sensor is effectively a loop of wire. When the pads wear down, the wire begins to contact the rotor. All is still well, until the rotor wears through the wire. Then the sensor indicates "Brake Linings." I would spend the $2-5 on sensors from RockAuto, long before disabling an option on the vehicle. Such as these CENTRIC SENSORS Why Centric? Because they have a length about an inch more than the others I'd looked at, and I wasn't comfortable the last time I put shorter ones on. Putting the electrical connectors in the holder mounted to the hub assy. made the wires very tight.

As Zombie stated, the OBC Tests are carried out on the small "clock, mpg, dist, etc..." screen. The warnings on instrument cluster will not interfere.
thanks again Einstein for the info/link, ill have to wait til after dark to run the test since i can only see the display at night with the lights on. oh i just remembered the guy i bought the car from told me the AC was working good & said the switch started acting up & it doesnt work at all now. how likely is it that its just the switch & not something more serious?
& does anyone have any ideas which relay could be clicking under the back seat when i hit the windows/sunroof switch, what is its function & why is it clicking...a short, its going bad......?
First thing I'd do with A/C not working, buy a can of refrigerant with a fill gauge attached from the local auto parts store and follow it's directions.

The A/C pressure may have simply been fading (leaking) for the previous owner. And when the car got hotter, and the pressure was enough to deactivate the cut-off sensor regarding refrigerant pressure it would work. Fill it, or make sure it's full with a can of refrigerant. I'd expect you have R134a, and you can check the aluminum freon lines. If the valves with the tire-valve-like (hopefully they are there) covers on them are your valves. The larger one, on the larger line is the one to focus on. Probably the most accessible IMO. It will either have threads on the outside of the valve or on the inside of the valve with a quick lock type of connection on the outside. If it's the thread inside one, it should be R134a. That would be best, as it is simplest and cheapest to deal with.

Relays click when activated. I am not sure why it would be loud. Internally it's an electromagnetic coil that attracts a gate which closes a higher amperage connection. A strong pull or loud click is not indicative of any failure that I would expect.
Thanks again Einstein for sharing your knowledge....i actually found an AC switch on eBay for $12, do u think i wasted my money? & after thinking about it the clicking might be so loud because i havnt bothered putting the backseat back in since i need access to the battery, so nothing to dampen the sound.

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I was even going to ask you if your back seat cushion was in place. Of course it's audible without that big noise barrier.

I wouldn't say you wasted your money on the switch at this point, I would say we have no idea. Maybe, if the original owner was savvy, and had already diagnosed this you're good. But in my experience, 9 out of 10 times it's low on refrigerant do to a faulty o-ring. Sometimes even the fill valve. I once had to tell an idiot not to stick a screw driver down into the valve. He was attempting to purge the system to see if freon sprayed out. Problem is, you can damage the sealing surfaces very easily. Anyhow, I'd bet on a bad seal and leaked freon first, that's all I mean to convey. You can buy seal kits and replace them, or they make leak sealer additives... Which I have zero experience with. Of course this is all provided it is low in the first place. As I said, get a can with fill gauge attached. Simple, no dirt under the finger nails or fuss way to figure out where you stand.
Yea lol i might be a bit of a space cadet at times (seat not in & wondering why the relay is clicking loud is a prime example lol) but i wouldnt go at valve like that with a screwdriver maybe an ice pick but never a screwdriver lol j/k. ill def look into the freon thing though

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ok i did the #9 OBC test & it read 0.08 is that normal?
& i am curious as to how many of those window regulator clips do i need for each window?
Unless I overlooked something and our OBC4's are not the same, that should be 13.5-14.5 volts.

There are two of those plastic sliders per window.
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