[NZ00Z3]

Silly question time.

Your old style E36/E39 black plastic/rubber key. Does it have 2 buttons or 3 buttons?

 

[OURMANDAN]

The key I have is not the diamond key but the older style one (I think commonly used on E39, idk if its euro specific).
Also I just had another look and I THINK THE SECOND WIRE FROM LEFT IS BROKEN! (as well as second from right)
View attachment 952485
Do you know where its supposed to go?
Oh and its the second WIRE but not the second connector pin. The first pin is not used so the broken wire is on the 3rd pin I think. I can double check in the morning

What you said is correct. pin 1 is empty, pin2 has the wire of interest for the key fob , and pin 3 is the butt cut wire you are featuring here. I know that's strange .. but that's how BMW did it. They have a cut wire connected to every other of the 1st pairs on the connector.

Please answer my never ending questions in panel 39.

Here's my rear window :

The trick is to determine is that connection is still made to the rear window. However as I sat around growing tired of Dr. Phil today .. I remembered a trick I read on a (very) old post that will tell us what we want to know. You mentioned you have a VTVM . Set it to the closest scale ABOVE 5 VDC. Ground the black wire to the stud or similar up there by the antenna box. touch pin 3 (blue wire) . You can do that with the probe I think, (on those occasions when I cannot .. I use an alligator clip and a safety pin to make an ultra sharp .. thin probe) . With your 3rd hand, push each of the buttons one at a time. The pulses are on average equal .. so your meter should average the pulse stream down to about 2.5 VDC on you meter. You will know its pulsing if you see that. Try it for each of your buttons .. BTW NZ or MrMCar asked how many buttons you had on your original Fob.
Is it 2 or 3 buttons? I know you posted a photo

We are getting close. This morning I swapped out myAMP (my photo here is the swap in). I swapped it after the first one failed this AM as the interior got hot. I brought it in from a cool garage & hooked it up fast to see if it worked .. then quit when it got hot. It actually didn't work the moment I put it in the car. But now (late afternoon and a drive with windows down) the car has cooled off and it works fine100%. This IS a heat related issue .. but I don't think the amp. It might be partially the amp. I'll roll out early tomorrow & see if I can develop a curve. Hey I think you mentioned that your central button works fine all the time ... but did you test it at the SAME time your FOB is acting up .. lock unlock, lock unlock? as Sapote pointed out in earlier threads, its behavior has significance.
Its also why I'm asking how many relays you replaced. Were you able to hear the quite relay click under the glove box when the locks weren't working?
In my case the trunk still works after the doors have quit but I have to hold the button down a full second or so. This is meaningful, and I'd like you to play around & see if you get the same behavior. Sometimes the doors get around to it also. this suggests either a relay issue which is possible (and has been heralded as "the solution" in posts back to 2004ish). or that the GM5 is misinterpreting the data stream when under heat stress. I have an unusual relationship with that 68HC processor in a past life, Who knows ... hopefully us soon. PS if I didn't mention it .. I have a 4 window coupe.

 

[MadJoeMak]

What you said is correct. pin 1 is empty, pin2 has the wire of interest for the key fob , and pin 3 is the butt cut wire you are featuring here. I know that's strange .. but that's how BMW did it. They have a cut wire connected to every other of the 1st pairs on the connector.

..... Please answer my never ending questions in panel 39 .....
Here's my rear window :
View attachment 952519


The trick is to determine is that connection is still made to the rear window. However as I sat around growing tired of Dr. Phil today .. I remembered a trick I read on a (very) old post that will tell us what we want to know. You mentioned you have a VTVM . Set it to the closest scale ABOVE 5 VDC. Ground the black wire to the stud or similar up there by the antenna box. touch pin 3 (blue wire) . You can do that with the probe I think, (on those occasions when I cannot .. I use an alligator clip and a safety pin to make an ultra sharp .. thin probe) . With your 3rd hand, push each of the buttons one at a time. The pulses are on average equal .. so your meter should average the pulse stream down to about 2.5 VDC on you meter. You will know its pulsing if you see that. Try it for each of your buttons .. BTW NZ or MrMCar asked how many buttons you had on your original Fob.
Is it 2 or 3 buttons? I know you posted a photo

We are getting close. This morning I swapped out myAMP (my photo here is the swap in). I swapped it after the first one failed this AM as the interior got hot. I brought it in from a cool garage & hooked it up fast to see if it worked .. then quit when it got hot. It actually didn't work the moment I put it in the car. But now (late afternoon and a drive with windows down) the car has cooled off and it works fine100%. This IS a heat related issue .. but I don't think the amp. It might be partially the amp. I'll roll out early tomorrow & see if I can develop a curve. Hey I think you mentioned that your central button works fine all the time ... but did you test it at the SAME time your FOB is acting up .. lock unlock, lock unlock? as Sapote pointed out in earlier threads, its behavior has significance.
Its also why I'm asking how many relays you replaced. Were you able to hear the quite relay click under the glove box when the locks weren't working?
In my case the trunk still works after the doors have quit but I have to hold the button down a full second or so. This is meaningful, and I'd like you to play around & see if you get the same behavior. Sometimes the doors get around to it also. this suggests either a relay issue which is possible (and has been heralded as "the solution" in posts back to 2004ish). or that the GM5 is misinterpreting the data stream when under heat stress. I have an unusual relationship with that 68HC processor in a past life, Who knows ... hopefully us soon. PS if I didn't mention it .. I have a 4 window coupe.

Seems like the wiring on the defroster is fine then... As seen in the yt video I posted, the trunk release and central button always work perfectly, even when the doors dont.
Since my car is from May 1998, this is my original (24yo OEM) key with 3 buttons: I also have another one thats beoken, the grey one and the emergency black one.

The key usually unlocks only the drivers door but sometimes it unlocks everything and locks and unlocks it about 2 times before not working again (All within a minute).
I replaced both relays in the GM5 but this made no difference at all to the behavior.

So to quicly recap everything:
The only affected things are the remote function that never works and the door lock which sometimes works. Everything else controlled by GM5 (including central button) works fine. The door locks have been acting up for a long time, the remote function hasnt worked for 2 months or so.
Its not the relays in GM5.

PS: The battery in the keyfob has been replaced already and the LED lights up brightly when I press buttons

 

[MadJoeMak]

Silly question time.

Your old style E36/E39 black plastic/rubber key. Does it have 2 buttons or 3 buttons?

check post above

 

[OURMANDAN]

check post above

I assumed from the start its not the relays. I replaced mine a year ago.
I saw you'd replaced the 2 relays Mad Joe, Recapping ... my car ALSO allows trunk unlock when nothing else works (let's say its last to fail). But when it gets hot in the cabin none of it work. I re-asked about your central lock because I hit mine when it was hot yesterday . and for the 1st time it didn't work

I've replaced my driver's side lock assemble. Did you know there are 2 motors in there? one for lockup/lockdown .. and the 2nd for "double lock". Which really means "pull handle twice to open door once. I'm not sure about the 36 .. but on my ride if you unlock the door with central you MUST pull the handle 2x to open the door.

So at this time I'm satisfied that our receivers are working, & suspicions the Antenna amps aren't shaping the signal square seem unfounded.
The GM5 must be mis-decoding data. The trunk may work better because its pulse pattern is coincidentally easier decode*.

The processor itself is not gonna be the problem. So the 2 most likely culprits? 1.) 5Volt power regulator circuit is not delivering exactly 5 Volts, or its not smooth DC (dried out capacitor(s))

I'll test that on my car over the weekend & let you know I I find something

*(If anyone reading this cares I ran into this with digital CTCSS aka. "DCS" hamming codes when designing 2 way radios ..a prior profession).

 

[MadJoeMak]

*(If anyone reading this cares I ran into this with digital CTCSS aka. "DCS" hamming codes when designing 2 way radios ..a prior profession).

I leanred a bit about hamming code in school. Pretty cool.

Anyway I will do some more troubleshooting when I get time. Ill test everything again when its really hot in the car and also measure the voltage from the amp in the c pillar.

The capacitors you were talking about, are they inside the GM5? I could easily replace them if I find a wiring diagram with the right values.

 

[OURMANDAN]

OK .. Recapping
We know you are at a stressful moment ..so don't want to give you too much to do but we are very close. I got mine fixed this AM. It was something I would never have guessed if I didn't have an actual RF tester beside the key this AM. The unlock button ITSELF was intermittent. 100% sure. Trunk key was fine just like yours as was the lock button.

Fasten your seat belt my friend ... I fell asleep before I was done last night .. dind't mean to keep you in suspense.

Let's get this #$% working this weekend. Mine worked perfectly the 1st time this A M. A miracle for sure. I'll link you the video in a minute ...but let's deal with your plan first

When doing FCC "type acceptance" paperwork for my job long ago, I noticed US UHF business radio channels overlapped Euro TV.
Our UHF radio band coincided with European TV )about 300-450Mhz.

So trying to develop my "RF test with a Voltmeter" I I searched around and something I didn't expect to find. I linked it below.

(I assume you have a TV to watch Dr. Phil every day to keep you sane till your locks are fixed)

Test 1.)

-Run the test below starting with the trunk button. Because we know it works, and therefore should display

-If you use cable TV you'll have to switch to "on the air" mode and use rabbit ears or better still is a piece of copper wire about 6 inches long and stuck into the the center of your cable connector.

Euro Key FOB test

Let me know if that works. My #1 guess right now is your FOB is sending signal only for Trunk ..

If that doesn't work ... don't worry I've already made a video for you using a trick with your voltmeter so we can glean the same info a slightly more awkward . but equivalent way
I already made a video for you
---------------------------------------------------------------------------------------

2.) This Input current test Needed only if Test 1 does not yield results.

I assume your key has button Lithium or rechargeable battery ..
In my video I forgot to flip it over.

I just un-soldered the + pin on my OEM fob and used a cardboard square so it could not touch its pad then I used 2 alligator clips (blue & White) to place my red and black Meter wires in series with the batter

You'll need to concoct a method to get the wire in series with the battery if you have a LION battery.

Before you connect ...
Set your voltmeter up to read milliamps (ma).
set your scale at the first setting over 10 ma.
Move the (meter -side) red probe to the ma socket on your Voltmeter. (unlike Volts testing current (Ma) testing makes your probes behave as a bare wire short. So keep them clear of circuit parts).

The goal is to compare input current flow for each button. I explain that in the video.

Video of input current Test for MadJoe

First we can determine if your key is sending at all for each key. If it is, we then need to evaluate if its sending correctly on each key .. that's a little tougher but not too bad.

Test 1: input current test.

Push each button one at a time. & see if similar current flow when you push each key..


I'll check back about 8:30 -9 AM your time it's 1:26 PM here and 10:26 PM in Austria. If you aren't there its OK.. You've already explained its a bust time for you.
If you can't reach the videos lemme know Asap so I can fix them

Best regards,
-OurManDan-

P.S. if these 2 tests don't uncover a key problem, we'll next have to test the 5VDC in the GM5 box. To do that you'll have to pull it out and extend a few wires to the passenger floor so we can measure both AC and DC components of that. Are you the guy that has an Oscope? We don't need it ..but its nice if we have same.
I can't recall if that was another person.

 

[OURMANDAN]

It has been an interesting night is is 11:13 p here so you are likely up. I am writing this before I hit the mat for the night because it may be quite relevant. So this was our first 100 degree day in Arizona (a really hot place in the summer). I have an RF tester, so I can tell when my key is sending .. not contents .. but that is has an RF carrier present. (Same thing we're trying to determine with your key in 1 of 3 ways I offered .. The TV test, the (2.5V) Antenna amp test with a voltmeter, and then the Input current test .

My key fob definitely an issue on the unlock switch which I fixed and thought that was the end. But this evening a much stranger thing happened. It was after dark and i decided to remove the glove box to do 2 things ... bring out 5VDC from the GM5 and maybe change the driver door relay while I'm in there. I had the classic thing where 1 of 10 times the driver side doesn't pop up though the other does.
I pulled the glove box out about 6 inches.. then decided I'd had enough for the day. I pushed the box it back in and put the screws (6) back in. That's all I did. When I hit the remote to lock almost nothing happened. including the trunk this time. My RF tester said the key was sending fine on all buttons .. but nothing was happening at the car.

There was one VERY important thing that did happen. It was dark out, & I noticed the interior light came on without fail when I pushed a button ...but no lock action. This I 'm trying to resolve .. everything dead but receiver clearly was working since interior light came on. i had only moved the glove box a few inches.

The only thing behind the glove box is the wires and connectors that attach to the GM5. So .. I pushed on the soft back of the (fully re-screwed in) glove box. The INSTANT i did that all the locks came back on and operated perfectly the rest of the evening.

I know those GM5 connectors.On the left there's a little latch, in the middle (X253) clicks down with tabs to lock it in there. The one on the right has a little side-slider that when slid right to left, brings the connector down onto the GM receptacle and locks it in place.

So Joe, I am expecting to see one or more of those connectors not full engaged, therefore leaving one or more pins intermittent, ..maybe sensitive to heat/cold.

I hope this does not sound far fetched, but i know you have yours out because you changed the relays.

Can you chose and carry out a key test, to verify the key is working 100% all three buttons, then assuming it does, Determine if your interior lights are still coming on with fob press though else works. If that's the cse maybe pull that glove box out, check those connectors for full engagement, and put a little electronics cleaner on before you close it up.
X253 (in the middle) seems to carry all the signals we care about (locks).

Access the GM5 module.

4:37 how to get the glove box out
8:13 How to remove the plastic tray that is very brittle
9:55 Description of the connector locking mechanism. Be sure you did this right . Inspect for loose pins and correctly done lock-downs on X253

Here's where the photo came from There is a pin out there as well.

GM Module info

I have your messages tied to my cell phone now .. so I'll get back toyou almost anytime tomorrow in 10-15 minutes.

I wish you the best.

 

[OURMANDAN]

I am not sure this will be helpful in any way, but here I am Sat testing my key while holding my RF checker in hand.
Ourmandan testing his key with RF detector

Except when I turned off the check with my thumb .. you can see my unlock key did not light up. So that was a real problem .. but not my only problem as we discussed
I'm off to get something .. When I return I'll be yanking that Glove box out of there to have a look at the GM5 connectors

 

[MadJoeMak]

I am not sure this will be helpful in any way, but here I am Sat testing my key while holding my RF checker in hand.
Ourmandan testing his key with RF detector

Except when I turned off the check with my thumb .. you can see my unlock key did not light up. So that was a real problem .. but not my only problem as we discussed
I'm off to get something .. When I return I'll be yanking that Glove box out of there to have a look at the GM5 connectors

I cant thank you eneough for all the time and effort. Im sorry for responding late but it is true that im learning for my finals atm and have basically no time. Also thank you for understanding.

One thing I should have clarified is the trunk release. What I meant is the button on the trunk lid opens the trunk, the button on the keyfob does not. That being said, it does look like a key problem so I will test the RF asap with whatever tools I can find and also do the second test you showed.

I checked the functions again when my car was boiling hot inside, the centre button still worked.

Also, you menitoned there might be a loose connection in one of the connectors. This may be the case actually. My box only uses the 54 and 15 pin connectors and when I tried to remove the 54 pin one, the tab that holds it in place disintegrated in my fingers so I had to use cable tie to hold it in place. I will also try pushing it in with my hand to see if it makes any difference.

When I push buttons on my fob, the lights do not light up like what you described. There is no action at all when I press any of the 3 buttons on the fob. Another indication that it is the key that is the problem.

Oh and I do not have a TV (because no one ever used it) but I do have the connector in my house and an antenna so I can probably do the first test, will look into it.

I will get back to you when I have done some tests and thanks again for the help. Let me know if youd like me to run any tests to help you out as well!

 

[MadJoeMak]

I am not sure this will be helpful in any way, but here I am Sat testing my key while holding my RF checker in hand.
Ourmandan testing his key with RF detector

Except when I turned off the check with my thumb .. you can see my unlock key did not light up. So that was a real problem .. but not my only problem as we discussed
I'm off to get something .. When I return I'll be yanking that Glove box out of there to have a look at the GM5 connectors

Ok so this will sound a bit dumb. You know when there is a problem that so complicated and you think you will never see the end? And then it turns out to be the simplest solution you have ever seen? Thats what just happened. Let me explain:

I just went out to do the test on the blue wire from the amp box. But before I did that I just decided to try the key one last time. I took the cover off the back, wiggled the battery and then put it back together again. Low and behold, IT WORKED! It was the battery all along. I feel so stupid right now but you cant blame me because the red LED on the key always light up when I pressed buttons so I always assumed the Key was ok. Lesson learnd, never assume anything, even if it has a control light.

So now after all that I have figured it out. However the physical key in the lock still only workes intermittently, which is probaby just a loose conneciton, however I dont plan on fixing that any time soon and I could probably figure it out myself.

Please let me know if you need anything to solve your peoblem, I am willing to help.

And with that I consider this case closed. Sorry for wasting your time...

 

[OURMANDAN]

Ok so this will sound a bit dumb. You know when there is a problem that so complicated and you think you will never see the end? And then it turns out to be the simplest solution you have ever seen? Thats what just happened. Let me explain:

I just went out to do the test on the blue wire from the amp box. But before I did that I just decided to try the key one last time. I took the cover off the back, wiggled the battery and then put it back together again. Low and behold, IT WORKED! It was the battery all along. I feel so stupid right now but you cant blame me because the red LED on the key always light up when I pressed buttons so I always assumed the Key was ok. Lesson learnd, never assume anything, even if it has a control light.

So now after all that I have figured it out. However the physical key in the lock still only workes intermittently, which is probaby just a loose conneciton, however I dont plan on fixing that any time soon and I could probably figure it out myself.

Please let me know if you need anything to solve your problem, I am willing to help.

And with that I consider this case closed. Sorry for wasting your time...

I am SUPER happy you figured it out. I was dreading suggesting your Key .. because I knew you believed the key was OK. But all signs were pointing to it. If your cabin light didn't come on (which I assumed you hadn't considered) it would be the key FOB. I knew we needed a way to test it .. I was fishing for a way. It may be something that's NOT the battery loose in your key .. but now at least you know what it is.
You said your old key was melted or something .. but if you can resurect its guts and still have the blade, finding an enclosure for it should be child's play.

I had 2 eureka moments myself;
1.)
first was when I hit the key after dark. Nothing worked, except the cab light. I usually use that test when I'm helping someone pair a Key to the car; The key won't pair unless the doors are shut.. sometimes the "door shut" detector has failed . so the GM won't allow the pair. So I test that all doors turn on the cabin light ... which is really testing that the door close detectors are all working.
But in my case noticing it came on confirmed the receiver & decoder was working.

2.)
Second was when I pulled the glove box out 3 inches then pushed it back in & everything started to work. At that moment I knew it was a mechanical issue on the X253 or the circuit board its attached too. I'll never know which it was, as I just removed the solder from the relays (but did not remove the relays) and corrected the crappy solder someone had left for me to fix, Then I used a toothbrush and professional spray on connector cleaner on the X253. and its connector.
I did the relay re-solder because I can read the "make" dates on the relays ...the ones that were there were much newer than the car. The solder was medium- bad so its also possible the pressure the glove box was putting on the circuit board via the connector was determining if the relay pin was touching or not.

Its perfect now!

I believe a whole lot of relays get changed that don't need changed. Everyone overlooks that there are a LOT of contacts on the X253 ..and the pins aren't gold plated at all. I'm guessing, but I believe a lot of relay changes did nothing except to cause the X253 connector to be pulled out and back in .. thereby scrape-cleaning the contacts. I bet a little contact cleaner and a toothbrush on the X253 would save a whole lot of frustration for many.

If you do that math on a 2003 Coupe on how many times a day the lock relay engages over how many years... you find out its a LOT less that other devices using relays and the relay is sealed . Maybe I'll put up a little article about that.

So ...we did both end up winners!! When you look to test that key and/or resurrect the other .. Just use the little voltmeter trick at the Amplifier/blue wire & you'll know
right away if that Fob is sending anything

I hope you are not mad anymore Joe!

Take Care !!!

P.S. my kid finished his college finals up last week.

 

[MadJoeMak]

I am SUPER happy you figured it out. I was dreading suggesting your Key .. because I knew you believed the key was OK. But all signs were pointing to it. If your cabin light didn't come on (which I assumed you hadn't considered) it would be the key FOB. I knew we needed a way to test it .. I was fishing for a way. It may be something that's NOT the battery loose in your key .. but now at least you know what it is.
You said your old key was melted or something .. but if you can resurect its guts and still have the blade, finding an enclosure for it should be child's play.

I had 2 eureka moments myself;
1.)
first was when I hit the key after dark. Nothing worked, except the cab light. I usually use that test when I'm helping someone pair a Key to the car; The key won't pair unless the doors are shut.. sometimes the "door shut" detector has failed . so the GM won't allow the pair. So I test that all doors turn on the cabin light ... which is really testing that the door close detectors are all working.
But in my case noticing it came on confirmed the receiver & decoder was working.

2.)
Second was when I pulled the glove box out 3 inches then pushed it back in & everything started to work. At that moment I knew it was a mechanical issue on the X253 or the circuit board its attached too. I'll never know which it was, as I just removed the solder from the relays (but did not remove the relays) and corrected the crappy solder someone had left for me to fix, Then I used a toothbrush and professional spray on connector cleaner on the X253. and its connector.
I did the relay re-solder because I can read the "make" dates on the relays ...the ones that were there were much newer than the car. The solder was medium- bad so its also possible the pressure the glove box was putting on the circuit board via the connector was determining if the relay pin was touching or not.

Its perfect now!

I believe a whole lot of relays get changed that don't need changed. Everyone overlooks that there are a LOT of contacts on the X253 ..and the pins aren't gold plated at all. I'm guessing, but I believe a lot of relay changes did nothing except to cause the X253 connector to be pulled out and back in .. thereby scrape-cleaning the contacts. I bet a little contact cleaner and a toothbrush on the X253 would save a whole lot of frustration for many.

If you do that math on a 2003 Coupe on how many times a day the lock relay engages over how many years... you find out its a LOT less that other devices using relays and the relay is sealed . Maybe I'll put up a little article about that.

So ...we did both end up winners!! When you look to test that key and/or resurrect the other .. Just use the little voltmeter trick at the Amplifier/blue wire & you'll know
right away if that Fob is sending anything

I hope you are not mad anymore Joe!

Take Care !!!

P.S. my kid finished his college finals up last week.

Great to hear. So your problem is completely resolved then?

Yes thanks for the video about the amp metre.

Also well done to your kid! He/She is probably the same age as me.

I now kinda wish the problem was something more than just a loose contact or whatever it was but at least I dont have to order parts from BMW.

Best regards! And also thanks to everyone else who helped in this thread.

 

[OURMANDAN]

Great to hear. So your problem is completely resolved then?

Yes thanks for the video about the amp metre.

Also well done to your kid! He/She is probably the same age as me.

I now kinda wish the problem was something more than just a loose contact or whatever it was but at least I dont have to order parts from BMW.

Best regards! And also thanks to everyone else who helped in this thread.

I like simple !

 

[Sapote]

I took the cover off the back, wiggled the battery and then put it back together again. Low and behold, IT WORKED! It was the battery all along. I feel so stupid right now but you cant blame me because the red LED on the key always light up when I pressed buttons so I always assumed the Key was ok.

How could the LED light turned ON when pushing the button and still the battery connection problem was the problem? Can someone explain this? I guess the remote Processor chip was in a crash mode and needed a RESET, and so by wiggling the battery that might have reset the control and it works again.

 

[OURMANDAN]

How could the LED light turned ON when pushing the button and still the battery connection problem was the problem? Can someone explain this? I guess the remote Processor chip was in a crash mode and needed a RESET, and so by wiggling the battery that might have reset the control and it works again.

That's a pretty good guess. I have never seen the inside of that type key. I have an ebay key which has 1 cell , but a split pad (looks like they were trying to make room for a trace on the opposite side of the board). So the makers were counting on the battery being flat enough to bridge left and right half of circuit board.
That's all I could think of. I absolutely do know of 1 pattern problem on the diamond keys that will screw up the data stream so any tool shows transmit, but the BMW can't make sense of it.
But not his key.
I wonder if the battery had enough juice left to light the led dimly (1.6 Volt and maybe .002 amps) ... but not enough to power the transmitter (.011 amps) . With the battery having rested the last month while MadJoe & I were trying to figure it out, maybe the battery recovered enough to work .... once or twice (laughing) . But as of 2 days ago I became convinced it WAS the key. After that I was just trying to proof it by making it visible.

It could be something else en the FOb that's come unsoldered but still touches if you wiggle it.

Hey it was a brutal 120 here yesterday. I had no issues with my coupe. thanks again for that lesson in chasing air out. I saw the broken stick bob up , so I caught it and put a small blob of epoxy at the top ... so it will stay put now. I like it better this way than with it sticking up out of the top.

OK I'm done thanking you now ... Take care.