Xoutpost.com - Keyless unlock doesn't work.

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xacto knife, there's a Youtube video on replacing the battery.

Quote:

Originally Posted by Qsilver7 (Post 967071)

If you have a battery charger...you can hook it up to the jump start posts in the engine bay, then insert your remote key into the ignition and turn it to POSITION 1...leave it there overnight (for up to the 30 hours needed to fully charge your key's battery).

The battery inside the key only charges when the ignition is in KL-R (position 1) or KL-15 (position 2) or KL-30 (position key returns to once engine has started)...using a battery charger hooked up to the jump start posts....prevents the car's battery from draining (which you don't want to happen with the key in the ignition...doing so has been known to kill the key).

THIS WORKS!

Thanks for the tip. I had some flaky remotes and one dead one, searched high and low, and this was the only true charging method I found that did not require enduro driving. Before doing this, I tried putting all remotes on the same key chain, and drove like that for a couple of weeks, but I guess not enough charging time there. Two fobs were still flaky, and the one diamond key was still dead (still started the car, of course).

I did Qsilver7's tip last night, with the diamond key in the ignition, turned to ACC (I), with the two flaky fobs rubber banded on either side of it. Car charger hooked up to the engine bay charging points to prevent battery from dying.

So today, after overnight charging, the two previously-flaky key fobs (cut from eBay diamond keys) are rock solid again. The diamond key is still dead as a doornail, so I guess it will be going in for surgery soon.

Question - before taking the diamond key apart, is it worth trying to reprogram all remotes? I would think that since all 3 other remotes work fine, and one works not at all, that it is not a problem on the car-side.

Quote:

Originally Posted by oldskewel (Post 1103886)

...
Question - before taking the diamond key apart, is it worth trying to reprogram all remotes? I would think that since all 3 other remotes work fine, and one works not at all, that it is not a problem on the car-side.

Give it a try...you have nothing to lose and all to gain. Reinitializing all the remotes (as long as they're done during the same session)...will give all of them the new rolling code table from the GM. They will either all work...or the 2 that are working now...will still work...and the dead one will still be dead.

Good luck. :)

make sure all doors are closed
make sure all doors are UNLOCKED
only insert the 1st remote into the ignition
2nd & 3rd remote...start on STEP 3 where you start pushing the buttons

http://bimmerboard.com/members/q/ori...ote%20Keys.jpg

Reprogrammed all successfully just now. Surgery averted.

Thanks for the confident recommendation for me to proceed. I had programmed them all (4 actually = 1 diamond key + 3 fobs) when I first got the keys after getting the car. With the recent flakiness, I was hesitant to mess up the working ones. But after the overnight charging, and now this re-programming, they are all solid again.

So data point for people - the remote (FZV) functionality on one of my keys just went dead, with 3 other remotes working just fine, with nothing to suggest why the one key died. And it was revived simply by this reprogramming. So somehow the FZV programming can completely stop working on one key with no hardware problems anywhere.