Home Forums Articles How To's FAQ Register
Go Back   Xoutpost.com > BMW SAV Forums > X5 (E70) Forum
Fluid Motor Union
User Name
Password
Member List Premier Membership Search Today's Posts Mark Forums Read

Xoutpost server transfer and maintenance is occurring....
Xoutpost is currently undergoing a planned server migration.... stay tuned for new developments.... sincerely, the management


Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 05-08-2020, 10:03 PM
Member
 
Join Date: Feb 2019
Location: Usa
Posts: 20
Magnesiumnitrate is on a distinguished road
Do first gen BMW ‘smart’ keys fail?

This one is a head scratcher.

2010 E70 3.0

Comfort access

Key fob just stopped working wirelessly one day. No spare to compare to.

Occasionally the fob works. Out of habit today I clicked it waking out and it beeped at me. Then nothing.

Tried:

Changing the battery.

Doing the resync procedure (start in dash slot)

Tested:

No faults in the CAS ECU.

ISTA shows key #2 in the dash.

When checking the battery levels ISTA shows transmitter #3 as discharging but 1-2 and 4-10 as ‘okay’

ISTA shows a field signal strength of 0.

Theories:

Key lost CA/Central Locking programming somehow. It thinks it’s key 1 but the car sees it as key 2.

Key has a bad capacitor, occasionally enough power to transmit is obtained but most of the time it’s effectively dead. (Shot in the dark, no idea how these specific keys work)

*tinfoil hat*

Previous owner lost a key inside the vehicle, and it’s slowly dying and DDoSing the CAS system with battery status. (Key #3 ‘discharging’)


Questions:

Would a bad passive go module or diversity antenna/amp cause these symptoms without throwing ECU faults?

Are there any other common failure points that may cause these symptoms?

The fact that I’m not getting anything in ISTA except green boxes leads me to believe it very well may be an issue with the key. What are my options at the dealer? Is it possible the key just needs reprogramming?
Reply With Quote

Sponsored Links

  #2  
Old 05-08-2020, 11:12 PM
ard ard is offline
Member
 
Join Date: Mar 2006
Location: Sierra Foothills, California
Posts: 6,730
ard is on a distinguished road
Yes, keys fail.


Why would you not buy and program a second key?!? Heck, why wouldnt you have done that the week after you purchased the car. You are one lost key away from $$$$ and drama.


Assume youve read the pdfs on how CA works, separate radios for CA vs ignition, etc etc.....
Reply With Quote
  #3  
Old 05-09-2020, 12:38 PM
Member
 
Join Date: Feb 2019
Location: Usa
Posts: 20
Magnesiumnitrate is on a distinguished road
Welp. Finally got some codes from ISTA and it looks like I’m having communication issues between the CAS & several modules.

I found water in the driver side well so I tracked that to the boot that holds the wires running up into the lift gate above the D pillar. That’s fixed, but still the electrical issues.

All the codes indicate one way transmission issues.



Any thoughts? I’ve pulled the D pillar trim and Im looking around for corrosion or damage. It all looks ok and I can’t change anything by wiggling wires around so I don’t suspect physical loom damage.
Reply With Quote
  #4  
Old 05-09-2020, 12:50 PM
crystalworks's Avatar
Member
 
Join Date: Jun 2014
Location: SA, TX
Posts: 6,414
crystalworks is on a distinguished road
You inspect the cas antennas? We have a code for a cas bumper aerial at the moment but have bigger fish to fry (trans woes). I'm sure it's can give you their status in a diagnostic module?

And second ard on purchasing another fob. Expensive. But cheap insurance comparitively.
__________________
2005 X5 4.4i Build 04/05 Maintenance/Build Log
Nav, Pano, Sport (Purchased 06/14 w/ 109,000 miles) (Sold 8/15 w/121,000 miles)


2006 X5 4.8is Build 11/05 Maintenance/Build Log
Nav, DSP, Pano, Running Boards, OEM Tow Hitch, Cold Weather Pckg (Purchased 08/15 w/ 90,500 miles)

2010 X5 35d Build 02/10
Nav, HiFi, 6 DVD, Sports Pckg, Cold Weather Pckg, HUD, CAS, Running Boards, Leather Dash, PDC, Pano (Purchased 03/17 w/ 136,120 miles)
Reply With Quote
  #5  
Old 05-09-2020, 01:11 PM
Member
 
Join Date: Feb 2019
Location: Usa
Posts: 20
Magnesiumnitrate is on a distinguished road
Quote:
Originally Posted by crystalworks View Post
You inspect the cas antennas? We have a code for a cas bumper aerial at the moment but have bigger fish to fry (trans woes). I'm sure it's can give you their status in a diagnostic module?

And second ard on purchasing another fob. Expensive. But cheap insurance comparitively.
The antennas look good. If its what I think it is, yours is super easy to fix. I replaced my CA rear bumper antenna in about 3 minutes last year.

As far as I can tell there's no reason to believe that the reception is the issue. AM/FM/Weather bands all work and are crystal clear. Bluetooth works. I don't have any SOS system codes (that module got soaked). I have a really hard time believing that it has nothing to do with my water ingress but the CAS module is way up front and I had water in the trunk. I was fully expecting to find some gnarly corrosion but nothing. The loom looks fantastic and there's very little visible evidence that water was ever even there.

To make matters worse, I cleared the codes and now they won't come back. Good? I guess, now I'm questioning if there are actually any BUS issues at all. I've gone from the issue being the key, to the vehicle, and now back to the key as I can't find anything wrong.

EDIT:

BLEH! I bet the codes were from having the battery disconnected! Just considered that. Back to no code square one.

Last edited by Magnesiumnitrate; 05-09-2020 at 01:18 PM.
Reply With Quote
  #6  
Old 05-09-2020, 01:14 PM
Member
 
Join Date: Feb 2019
Location: Usa
Posts: 20
Magnesiumnitrate is on a distinguished road
Quote:
Originally Posted by ard View Post
Yes, keys fail.


Why would you not buy and program a second key?!? Heck, why wouldnt you have done that the week after you purchased the car. You are one lost key away from $$$$ and drama.


Assume youve read the pdfs on how CA works, separate radios for CA vs ignition, etc etc.....
I've had a key on my list for a while, but I have AAA and a bluetooth tracker for the one I do have. The tile (which is fantastic by the way) was much cheaper than a new comfort access key from BMW.
Reply With Quote
  #7  
Old 05-09-2020, 01:18 PM
crystalworks's Avatar
Member
 
Join Date: Jun 2014
Location: SA, TX
Posts: 6,414
crystalworks is on a distinguished road
Hmmmm. Interesting there's no codes now. One question that has to be asked whenever dealing with bus or electrical issues: how old is the vehicle battery?

Thanks for the info on the bumper aerial. Will look into that.
__________________
2005 X5 4.4i Build 04/05 Maintenance/Build Log
Nav, Pano, Sport (Purchased 06/14 w/ 109,000 miles) (Sold 8/15 w/121,000 miles)


2006 X5 4.8is Build 11/05 Maintenance/Build Log
Nav, DSP, Pano, Running Boards, OEM Tow Hitch, Cold Weather Pckg (Purchased 08/15 w/ 90,500 miles)

2010 X5 35d Build 02/10
Nav, HiFi, 6 DVD, Sports Pckg, Cold Weather Pckg, HUD, CAS, Running Boards, Leather Dash, PDC, Pano (Purchased 03/17 w/ 136,120 miles)
Reply With Quote
  #8  
Old 05-09-2020, 01:20 PM
Member
 
Join Date: Feb 2019
Location: Usa
Posts: 20
Magnesiumnitrate is on a distinguished road
Quote:
Originally Posted by crystalworks View Post
Hmmmm. Interesting there's no codes now. One question that has to be asked whenever dealing with bus or electrical issues: how old is the vehicle battery?

Thanks for the info on the bumper aerial. Will look into that.
Roughly a year old. I replaced it preventatively just after I bought the car. It was the original 10 year old battery so I figured it was going to leave me stranded eventually.
Reply With Quote
  #9  
Old 05-09-2020, 03:13 PM
crystalworks's Avatar
Member
 
Join Date: Jun 2014
Location: SA, TX
Posts: 6,414
crystalworks is on a distinguished road
Easy, but real expensive test... buy a new CAS entry key from BMW. If it works 100% of the time, your current key has a fault. If the new key is intermittent then something is up with the truck. Horrible way to go about diagnosis, but you need a new key anyway right.
__________________
2005 X5 4.4i Build 04/05 Maintenance/Build Log
Nav, Pano, Sport (Purchased 06/14 w/ 109,000 miles) (Sold 8/15 w/121,000 miles)


2006 X5 4.8is Build 11/05 Maintenance/Build Log
Nav, DSP, Pano, Running Boards, OEM Tow Hitch, Cold Weather Pckg (Purchased 08/15 w/ 90,500 miles)

2010 X5 35d Build 02/10
Nav, HiFi, 6 DVD, Sports Pckg, Cold Weather Pckg, HUD, CAS, Running Boards, Leather Dash, PDC, Pano (Purchased 03/17 w/ 136,120 miles)
Reply With Quote
  #10  
Old 05-09-2020, 04:27 PM
Member
 
Join Date: Feb 2019
Location: Usa
Posts: 20
Magnesiumnitrate is on a distinguished road
Well. Things get even weirder. I can fairly consistently get the comfort access controls to work. Further, after fiddling with them enough to activate I can get the car to recognize a command or two from the remote before going dark again.

If I recall correctly when I pulled my door handle off before it disabled all the comfort access features by breaking the circuit but I think the remote buttons still worked. Can anyone confirm this behavior? I only had it off an afternoon while I was swapping them so my memory is fuzzy.

New hypothesis is another failed door handle. Maybe a failing CA antenna that’s not throwing a fault for some reason? I know from experience that the door handle won’t throw a fault so that’s my best bet.

Last edited by Magnesiumnitrate; 05-09-2020 at 04:39 PM.
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On





All times are GMT -4. The time now is 04:04 PM.
vBulletin, Copyright 2024, Jelsoft Enterprises Ltd. SEO by vBSEO 3.6.0
© 2017 Xoutpost.com. All rights reserved. Xoutpost.com is a private enthusiast site not associated with BMW AG.
The BMW name, marks, M stripe logo, and Roundel logo as well as X3, X5 and X6 designations used in the pages of this Web Site are the property of BMW AG.
This web site is not sponsored or affiliated in any way with BMW AG or any of its subsidiaries.