Remote key problems ("not" recharging, can't unlock, no key memory)

[terano69]

Hi there

I got a bit of a tricky problem with my Bimmer. 4 months ago I bought a e61 523i, year 2005. The car is in really good condition but the remote key doesn't work. I have one of the 1st model of e61 that came with a "newer" square key with rechargeable battery. As far as I know 1st e61 with Start/Stop button. No comfort access.

Symptoms:

1) Remote key doesn't work, can't lock/unlock the car with it (none of the 3 keys I have)
2) I have to unlock the car manually (with the plastic key or the metal one that is clipped inside a remote control)
3) When I insert the key into the car I get a message on the dashboard that my battery is empty and I that I should charge it.
4) If I press start button car starts normally
5) No memory settings are stored on the key (which I guess is normal as the car things the key is battery is empty)

What I tried so far:

1) I've ordered new key from BMW and they program it in. But the thing still doesn't work. So obviously not a problems in the key.
2) I've pulled apart one of the old keys and measured the voltage in it and it was 3.14v which should be fully charged. Then I clicked and clicked the buttons on the same remote until the voltage drooped to 2.9v, put the key together and start the car and drive around for a bit. After 10min driving I've measured the voltage again and it was 3.14v. What that tells me is that the key is actually charging and is fully charged.
3) I've found on forum that many people have problems with diversity antenna under the spoiler. I've open it. No water damage what so ever. I've found a guy on eBay and drove to him and tested anew diversity antenna and the things still didn't work.
4) Next thing is I've checked is the cables that goes from spoiler next to the speakers in the back of the car. Also no damage found what so ever. All cables in good shape.

Does anyone had an idea what else should I check? I'm searching and reading forums for the last 2 months and I can find one single case like this.

Thank you in advance

[Pelican Parts]

Hello and welcome to the forum! It sounds like you have tried almost everything! Have you tried pulling any codes to see if that gives you any more information?

[terano69]

Last night I've also check all the fuses in the back and in the front of the car and they are all OK.

I was trying to find out which key is my master key as I have 3 of them, and when I check the Status actual key with INPA I got this screen: Is it normal to have "Key Locked" and black dot? Could this be the issue?

That's on my next to do list. I'm currently have INPA and NCS Expert 4.0.1 but I guess I need ISTA to get the error codes? I'll try and sort this out and report back.

Which modules should I test with ISTA?

Thank you in advance!