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TKrotchko
01-15-2006, 10:56 AM
I installed this kit about a year ago and its been problematic ever since.

Initially, it didn't work at all when I installed it. After checking the fuses I found it had blown the telephone fuse.

I replaced the fuse and it now responded to button presses. I attempted to pair with my phone and after a few seconds the female voice got very crackly and I smelled some burning plastic. After doing some searching, it appeared the pairing button was smoked (!).

I managed to more or less repair it and I got the pairing to work for about a day. I managed to pair my phone with it and it now works!

But, the pairing button will no longer work.

I ordered a 2nd button and it...smoked after I held it down for about 5 seconds.

I ordered a 3rd and it...almost smoked.

So some voltages are screwy somewhere. How can I diagnose the problem? The performance is flawless, but I'd like to get a new phone soon.

--Tom

Technic
01-16-2006, 05:02 AM
I installed this kit about a year ago and its been problematic ever since.

Initially, it didn't work at all when I installed it. After checking the fuses I found it had blown the telephone fuse.

I replaced the fuse and it now responded to button presses. I attempted to pair with my phone and after a few seconds the female voice got very crackly and I smelled some burning plastic. After doing some searching, it appeared the pairing button was smoked (!).

I managed to more or less repair it and I got the pairing to work for about a day. I managed to pair my phone with it and it now works!

But, the pairing button will no longer work.

I ordered a 2nd button and it...smoked after I held it down for about 5 seconds.

I ordered a 3rd and it...almost smoked.

So some voltages are screwy somewhere. How can I diagnose the problem? The performance is flawless, but I'd like to get a new phone soon.

--Tom

Tom

Check page 21 or 22 of this document: http://www.golilm.com/Docs/3SeriesInstallationBluetooth.pdf

... the schematic of all the connections in/out of the BT ULF module are shown. The pairing button is the "Interface switch". If look closely there are only three connections into the pairing button: pin 1 goes all the way to the BT module pin 32 (+5V), pin 2 goes to the radio or navigation unit, pin 3 is the light switch pin (look like it goes to ground once you turn on the lights for night illumination).

Taking the pairing button out of the equation (you are into the third button after all), I would guess that pin 2 is somehow shorted out or damaged somewhere between the radio/navigation unit and the pairing button. It looks like when you press the pairing button pin 1 and 2 are closed together, and a new signal -it was 5V in pin 1 by itself according to the schematic, you can check pins 1 and 2 with a voltmeter to find out their real signals- is sent to the BT ULF module for communication. If pin 2 wire is touching ground somewhere, by closing on pin 1 ground will be sent to the BT module pin 32 that has 5V, causing the pairing button to burn if that ground is not expected in that pin.

Check also in page 8 that you indeed removed pins 7 and 8 from the 54 pin connector before plugging the ULF module, you never know what these pins and their signals are doing to your module if they are hot.

Maybe the ULF is itself damaged, and pressing and holding the pairing button make the ULF to backfeed ground into the line and burn the button. Unusual, because you stated that you can make the ULF pair, but anything can be possible at this point without professional diagnostics by the dealer. :confused:

TKrotchko
01-16-2006, 10:09 AM
Tom

Check page 21 or 22 of this document: http://www.golilm.com/Docs/3SeriesInstallationBluetooth.pdf

Maybe the ULF is itself damaged, and pressing and holding the pairing button make the ULF to backfeed ground into the line and burn the button. Unusual, because you stated that you can make the ULF pair, but anything can be possible at this point without professional diagnostics by the dealer. :confused:

Thanks for the good advice. I'm going to go out there now and check the voltages coming in from the button.

I suspect that the guy I bought the kit from provided me with the wrong adapter for the button. OR, like you said, something is grounded incorrectly.

The fact that the system works perfectly *except* for the pairing button leads me to believe that the ULF module itself is okay. I also think its an important clue that a fuse blew when I first installed it.

Off to the garage for now...

TKrotchko
01-16-2006, 11:51 AM
It's now working, but I'm left with a puzzle.

Why?

I took out the ULF module and checked the harness. Pins 7 & 8 had never been part of the harness, so that wasn't the problem. I double checked the plug was installed on the other connector.

So I checked the wiring harness on the pairing. There was +5V between the ground and the pairing button and +5 between ground and the light. This all looked good.

So then I checked the button and I couldn't determine continuity either way. I was puzzled. So I took the switch apart (they come apart in 2 seconds) and I realized the switch I had in the car was the very first one and it was badly burned. So I found the 3rd one which looked good and tested it would short pins 2 & 3 when depressed. So far so good.

I tried it in the car (didn't install the switch). Nothing. But no smell of burning either. So I got out the manual and noticed to pair, you hold it down before you start the car and hold it for two seconds afterwards. Still nothing as I held it down. So I let it go after a few more seconds and 1 second later it flipped into BT PAIR mode. Dumbfounded, I turned off the ignition and tried again. 1 second before, 2 seconds afterwards. Wait a second. BT PAIR.

I reinstalled the switch. It seemed really tight (I cut the hole). So I filed to give it a little more clearance. Installed the switch again. tested it 2 more times. And it works.

So it's working, but I'm puzzled. Here's possible explanations:

1) Holding the BT PAIR button for more than 10 seconds will fry it. A possibility, but as they cost $35, I'd rather not try it again (plus the dealer will think I'm a kook, since he has to order them).

2) The very original button was bad, which might explain why switch #1 was badly fried and the fuse blew. That doesn't explain why button #2 burned (unless #1 is true again).

3) There is a marginal wire in the harness and moving some wires around in the trunk or in the console made them connect. Or something like that.

4) I'm going crazy (which might be true, but that doesn't mean there isn't a problem).

So as long as it works, I don't care how or why, and I can get that new phone.

Thanks for being a shoulder to cry on. At least it inspired me to go out there and get it working. Or something.

--Tom



2

Technic
01-16-2006, 01:47 PM
Ok... it helps to have the correct pairing button installed. :D

According to the ULF manual, pressing and holding the pairing button for 10 seconds delete all devices in the ULF memory. You should have seen some indication of this in your radio display the first time that you pressed and held this button. If not then the problem is still there.

You should check the voltages with the button connected, pin 1 should connect to pin 2 somehow when the button is pressed. Pin 3 is the light switch, so you should flip the lights on when checking this pin out.

If this is a recurring problem you will see it again, but only when the pairing button is connected...

TKrotchko
01-16-2006, 04:09 PM
Ok... it helps to have the correct pairing button installed. :D
You should check the voltages with the button connected, pin 1 should connect to pin 2 somehow when the button is pressed. Pin 3 is the light switch, so you should flip the lights on when checking this pin out.


I'll have to keep an eye on it.

But according to the pins on the back of the switch, its exactly reversed. Pin 2 is ground, Pin 1 is the light (blue wire), Pin 3 send the current back into the harness. I checked the new switch and its consistenly like this.

I didn't try to erase memory, so I guess I didn't hold it for 10 seconds. I'll try that when I'm feeling brave <G>.

ambishop
01-16-2006, 07:14 PM
Sometimes the ULF module pins get bent. Pull off the connector and look at the ULF module. If you look in good lighting sometimes you might find a pin that has bent over and may be shorting out on another pin.

Since you are talking a pairing button, I assume this is an E46, but I do not know the year. It makes a difference in the wiring. If you want to shoot me an email with details, I might be able to help you debug. I just started selling E46 kits, so I am sure it is not mine.... but I know these things pretty well.

Martin
www.bimmernav.com

TKrotchko
01-21-2006, 07:01 PM
I just started selling E46 kits, so I am sure it is not mine.... but I know these things pretty well.


I have a hunch what may have cleared this. When I installed this in the past, I did not pull the power from the battery. But in debugging, I pulled fuses 7 & 41 looking for an open fuse.

I'm purchasing an Icelink and it seems to be standard to pull 7 & 41 to reset the "communications stuff", which means, radio/satellite/phone and associated sub systems. I suspect that reset the ULF module and now everything is fine.

So far so good after almost a week. It's never worked this well before.