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stu535i

BMW single button remote programming (E32/E34/E36 etc)

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Ok here we have a rough-and-ready guide to reprogramming alarm keyfobs of the single button type shown below:

alarm2.jpg

I am assuming that you have:

a) A working (or known to have worked at somepoint) keyfob to copy.

B) A secondhand replacement keyfob to be programmed.

Reprogramming these takes about 10-15 minutes, you'll need a half-decent soldering iron, solder, and a de-soldering tool (solder sucker or copper braid).

Remove the screw from the back cover, then carefully seperate the back cover from the keyfob. Note the battery orientation, then remove the battery. You'll see the bottom of a circuit board as shown in the photo below. Note there is an array of 3 x 7 solder pads. The upper and lower rows of this array determine the 'code' for the keyfob, pads either have a blob of solder bridging the two halves, or no solder at all. Take a moment to examine your working keyfob and note how the solder has been deposited on the pads. The photo below shows a keyfob I found lying in the wheelwell of a 3 series in the breakers... note the 3 x 7 array shown with the red box around it.

solderpads.jpg

Now for the sake of example lets imagine that the code 'pattern' for your good keyfob is as shown in yellow below. Lets assume the orange pattern is the secondhand keyfob you have (incorrect). You'll see that most of the orange blobs are in the wrong position, so we de-solder these, removing all traces of solder where required. This leaves us with something similar to the third sketch below, where the only blobs of solder that remain on the array are in the correct position.

The next step is basically putting blobs of solder over the corresponding pads to match the positions copied from your 'good' fob, these new solder blobs are shown in the bottom most sketch below in red. You can see how now this keyfob matches the pattern of your original keyfob. Double check you don't have any stray blobs/short circuits from your hamfisted soldering :)

copying.jpg

Replace the battery, close the keyfob. Press the button to check you have the red led illuminate, if so go and test it with your car.

Easy :)

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Cheers Stu! I'm going to get a soldering iron and try this at the weekend. I'll prob burn my hand off knowing my ham fisted way, but I might learn a new skill too!!

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As long as you take your time Mark, you'll be fine.

Finally got a cure though for your alarm!!! :)

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Random (slightly associated) question:

Does anyone know where to get an emergency key for this alarm? The one that turns the unit off itself...

I'd love to know that too - been down to BMW Dealer and the local locksmith, no luck at either one. Locksmith won't touch it in terms of replacing the lock either.

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Well Ladies and Gentlemen, I had a go at the soldering, and as predicted, burnt my hand and wrecked the insides of the remote - couldn't get the solder to stick to anything!! That's the first lesson then - LEARN TO SOLDER FIRST!!

Anyone who has never done this before, and is thinking - "how hard can it be?" Don't kid yourselves!

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I'm a novice solderer myself so I reckon I'll have a few practice goes before I attempt anything in anger. I have a reasonable quality gas soldering iron, do you recommend I use this or should I be using a mains one? Or does it not matter one way or tother? :?

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Don't use a gas iron near a circuit board

Tin the tip of the iron with solder before doing anything, it tells you it's warm enough for a start!

You need a solder sucker, and make sure your solder is flux cored.

A damp sponge for wiping the tip of the iron is useful too.

It's easy, you can get soldering stands with clamps and a magnifying glass, makes life easier too.

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as predicted, burnt my hand and wrecked the insides of the remote

:lol: :lol:

Sorry Mark, thats class

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:lol: :lol:

Sorry Mark, thats class

Thanks MATE!! :x

Yep, bought the iron, the sucker, stand and sponge, flux cored solder, got some instructions ( all at Maplin ) and then came home and switched it on - it went a dark colour right away, and as soon as I tried to solder it started on me! Ended up the solder just ran off the bit I wanted it to be on, and ended up in the chip underneath. Then it tried to kill me! :oops:

I paid £25 for that fecquin remote too ( Mods note - that's not a swear!!!). Pants!

Time for a replacement security system!

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Don't use a gas iron near a circuit board

Tin the tip of the iron with solder before doing anything, it tells you it's warm enough for a start!

You need a solder sucker, and make sure your solder is flux cored.

A damp sponge for wiping the tip of the iron is useful too.

It's easy, you can get soldering stands with clamps and a magnifying glass, makes life easier too.

Thanks for the advise Robbo. 8)

I've now ordered myself an electric soldering kit, solder sucker and flux cored solder. I already have the clamps and magnifying lenses.

Now I just need to practice a bit and a secondhand keyfob to have a go on when I'm ready to go for it. What's the chances or breakers yards keeping old key fobs laying around or do they bin these sort of things?

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Use an electric 25w (or smaller) iron with a needle tip.

A sucker is damn fiddly to use (I know) on such small amounts of solder, gauze braid strip is easier and cleaner.

A small multimeter or continuity tester will allow you to test to make sure all your connections are good and the non-connected pads are indeed not connected.

Mark: Unless you have burnt the board (or one of the components) or the track on it, then it will be useable...just will need cleaning up and re-soldering.

If you are having problems seeing the pads, use a magnifier.

And certainly practice on a few larger things first!

If the solder is running off the tip, then allow the iron to get *very* hot...tin with fluxed solder (or flux and solder) and then allow to cool. Now lightly sand or file the tip..reheat and tin. This time the solder should stay on the iron tip.

but you should really apply the iron to the job, then the solder after the spot or wire is hot...that avoids excess solder on your job.

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Mark: Unless you have burnt the board (or one of the components) or the track on it, then it will be useable...just will need cleaning up and re-soldering.

No, I have burnt pretty much all of the components! Maybe if I had a few beers first...............

How do you tin the iron? No - forget that - I'm going to get someone to teach me how to do this - if I can get the innards of another fob or two cheap - I'm NOT paying another £25 just so i can cook it away again!

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Hi Alun,

It could be that you have a 'dry' solder joint somewhere, but first of all I'd check that the battery is making good contact with battery holder (it can get corroded/oxidised with age) - if so a little scrub with sandpaper or the wifes nail file should fix it, and obviously try a new battery if still no joy.

Stuart

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Hi guys, thought I'd bump this post riiiiight back up.

I'll get the unpleasantness over with...I bought an E36...sorry guys, I'll be in a 5 again at some point. Anyhooo

I've got a 1994 e36 but it didn't come with any fobs, luckily I still have the original build sheet which specifies the car has a 'BMW Approved Anti-Theft System 3', is this the same as the ones mentioned in this post? I'm trying to figure out what fob my car was supposed to come with. Hopefully from there I can then look into how/where to get another one that will work.

Any help much appreciated :)

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Good detail.

My cars problem was the Decoder module in the vehicle died.

I got a replacement from ebay and re-coded the Decoder. This was very tricky I had to first getthe schematics for the decoder chip part number MC145028. Then worked out the mapping of the address lines. They are either ON, OFF or OPEN connected. This had to match my key fobs.

I can you people with provide them with full decoder and encoder programming instructions.

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guys I have something that looks like that 1 button FOB, but not exactly on the inside, I have only one of these, I am trying to keep it as OE as I can, even when I retrofit or upgrade, always in the "factory options". I have an e36 1992 325is US specs. I am trying to find out how to program this and someone recommended me this thread from an e36 thread, that is why I am here. Here are the pics

 

http://www.bimmerfest.com/forums/attachment.php?attachmentid=466018&d=1411454594

 

http://www.bimmerfest.com/forums/attachment.php?attachmentid=466019&d=1411454594

 

http://www.bimmerfest.com/forums/attachment.php?attachmentid=466020&d=1411454594

 

If I dare to lose the remote I will not be able to start the car, and as I told you I really like the OE style, so, please throw me a rope here. I see a some little differences between my "working" FOB and the two "new FOBs" I have for reprogramming. Thank you for letting me be in your forum!!l

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Where could I find this case? I have searched lots of places, but haven't come across any, where I could buy it.

 

Mine ring holder noose broke off and currently have to wear key and remote separately.

Therefor if anyone knows, where I could buy or has some for sale, I would be grateful for the information!

 

 

WP_20160315_11_22_01_Pro.jpg

WP_20160315_11_22_18_Pro.jpg

Edited by taurib

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