Dead Key Part 2 :(

T

thanatu55

Senior member
My key has been acting up for a while. The first issue was that every now and then the remote locking would fail to lock or unlock while pressing the key buttons. I'd get angry, keep smashing the button and move around a bit and eventually it would work. I carried on making do until I had time to look at it.

Then after a while the remote locking with the key failed completely and I could only lock and unlock the manual way. I replaced the battery in the key but no luck. I posted a topic on this at the time and received some very helpful information about reprogramming/syncing the key, but none of the methods I've tried make a blind bit of difference. I've tried three different methods, nothing. I carried on making do until I had time to look at it.

This weekend I got round to testing the battery and key to make sure it was working and the result was positive, the key is working but the remote central locking is still not working. Today I gave the car a wash, then got in ready to take a drive and the car won't start at all. Position one and two work, all the dash lights come on, but position three does nothing. The car doesn't even turn over. I checked the car battery and all is fine there. I've searched through loads of forum threads for possible fixes but nothing has solved my problem. What's worse is that I only have one key, no spare, so I'm effectively stuck with a car that I can't use :cry:

Any ideas?
 
BMW CAR mag - the one with Fishy Daves Z4MR on the front - had a feature on these "diamond" keys that we get in the E85/6 Z. It says they can fail internally so the EWS immobiliser chip won't talk to the car. Dash lights on and maybe the sound of a relay clicking they said. BMW can supply one ready coded based on VIN but doubt that's cheap. They suggest that if going that route check the engine ECU casing VIN and chassis VIN match in case the ECU was replaced at some stage.
 
Thanks for the info, a lot of that does ring true... I do get a clicking noise which has been there for a while. I believed it was connected to the windows because when I closed the roof with the key the windows don't close and I get that noise. I wondered if the transponder may have been lost while testing the battery but I have no idea where it is or what it looks like.
 
http://www.bimmerfest.com/forums/showthread.php?p=5834572
Maybe of use. Suggests it's a chip on the circuit board so unlikely it's lost.
 
OK, the key relies on the internal battery for locking / unlocking and setting the alarm but it's the transponder that does the EWS (immobiliser) function and that is powered completely by the inductive loop in the cars ignition barrel.

If you cannot start the car with the key it has nothing to do with the internal battery - you more than likely have a duff connection in the key or a dead transponder chip. BMkeys or DLV should be able to sort for you maybe?

Just as a final last resort, I would do the following:

1) Put key on toothbrush charger over night (make sure the key is sat sideways against the lump in the middle of the toothbrush charger).

2) Perform the method 3 key programming:

Turn key to position 1 and back 5 times quickly
Remove key
Hold unlock button whilst pressing lock button 3 times.
Release unlock button
Turn ignition on to finalise
 
The locking unlocking issues could be GM5 module related.

The car not starting could be ignition switch failure. Easy fix for a tenner. Quarry motors.via eBay have them, and a ten minute job.
 
Thanks for all the suggestions... I have a diagnostic kit coming today (won on ebay) so I'm going to see if anything comes up on that.

I've tried the tooth brush charger and the programming method but no dice. I was pretty sure the central locking and the car not starting couldn't be related as the two are not entwined, I guess it's just pure luck that an avalanche of problems just happen to hit me at the same time. I've got a free afternoon to investigate everything later with my dad... he's much more technically minded than I am.

I'm the type to open the bonnet, glance at the engine and say "Yep, it's f***ed".

Hopefully it turns out to be one of the easy ones to sort and not something much more expensive :cry:
 
I had some key troubles recently too.

When my fob battery died i replaced it with rechargeable battery bought from eBay, when i tried to star the car i got the same symptoms you've mentioned, ignition would come on in position 1 and 2 but the car would not turn over and i could not code the fob to operate the central locking.

As soon as i removed the new battery, the car then started so i suspected the battery itself was the cause of the issue.

I bought another replacement battery and soldered it on a few days later, this time the car starts and the central locking now works fine (after a quick re program).

So yeah, could be the battery itself that's the problem as it seemed to be for me.
 
That's interesting :o .
I replaced the battery in my spare key having found it wouldnt charge though I hadn't tried to start the car with it (hadnt had the car long). It won't turn the starter but it does do all the remote things after re-syncing. Really odd that a new battery could affect the key being registered with the EWS?
So was the battery from a different manufacturer?
 
thanatu55 said:
My key has been acting up for a while. The first issue was that every now and then the remote locking would fail to lock or unlock while pressing the key buttons. I'd get angry, keep smashing the button and move around a bit and eventually it would work. I carried on making do until I had time to look at it.

Then after a while the remote locking with the key failed completely and I could only lock and unlock the manual way. I replaced the battery in the key but no luck. I posted a topic on this at the time and received some very helpful information about reprogramming/syncing the key, but none of the methods I've tried make a blind bit of difference. I've tried three different methods, nothing. I carried on making do until I had time to look at it.

This weekend I got round to testing the battery and key to make sure it was working and the result was positive, the key is working but the remote central locking is still not working. Today I gave the car a wash, then got in ready to take a drive and the car won't start at all. Position one and two work, all the dash lights come on, but position three does nothing. The car doesn't even turn over. I checked the car battery and all is fine there. I've searched through loads of forum threads for possible fixes but nothing has solved my problem. What's worse is that I only have one key, no spare, so I'm effectively stuck with a car that I can't use :cry:

Any ideas?
Click to expand...

Interesting, I have an almost identical problem .... but my central lock/unlock is still working. This is costing me a f***ing fortune. So far I have replaced the ignition switch, the battery and the starter motor. It fires maybe second twist of the key but more often than not first go ends up as described by thanatu55.
 
BoWzER said:
I had some key troubles recently too.

When my fob battery died i replaced it with rechargeable battery bought from eBay, when i tried to star the car i got the same symptoms you've mentioned, ignition would come on in position 1 and 2 but the car would not turn over and i could not code the fob to operate the central locking.

As soon as i removed the new battery, the car then started so i suspected the battery itself was the cause of the issue.

I bought another replacement battery and soldered it on a few days later, this time the car starts and the central locking now works fine (after a quick re program).

So yeah, could be the battery itself that's the problem as it seemed to be for me.
Click to expand...

That's interesting and useful to know thanks, I'm still stuck as is so I'll see if the battery does make a difference. I've just acquired some BMW Diagnostic equipment too so working through that for solutions but the software itself is a bit of a learning curve for me before I get to the actual problem solving!

I'll report back if I manage to get somewhere with this.
 
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