Comfort access failure..

[B21]

In the UK comfort access was rarely fitted..maybe different elsewhere…mine’s going south..here are some notes for other folks..

Comfort access failure!

Comfort access is a number of additional capablities added to E89s in addition to the normal key fob things.

The technologies and parts were widely used on a number of other BMW cars..but rarely fitted to the E89.

The only two obvious ways to see if you have comfort access (apart from a VIN check) is to see if each door pull has 3 raised ridges moulded into the handle AND if the fobs have a removeable non rechargeable battery CR2032..these two features define comfort access.

So what does comfort access do, if its working properly?

You can raise the roof on the fob..not possible with the standard system

You can unlock and lock the car by touching the 3 moulded lines with the fob in your pocket

You can start the car without inserting the fob into the 'slot'

Not earth shattering.

However it turns out its not a very reliable system, either on E89s or elsewhere.

The most common failure is the electronics in the door handle (quite complex with a microprocessor) fail..often resulting in an unexplained current drain warning / manin battery going flat if left..

Also remote operation of roof/windows/locks all start to go wrong in various ways..

In my case a red herring of current drain that I associated with the fittingof the ID4Cluster was my downfall..

The roof wouldn't open on the fob, a high current drain was shown on iDrive ..

I fitted a new battery..tried various things with matters getting worse..

I then noticed that when I touched the driver door handle with the car parked and cold that it was warm to the touch.

I've used a thermal camera to show the image and temperatures..nealry 50c on the driver door and 25c on the passenger door..with the rest of the car at 16c..

Its an expensive problem to fix..each door handle is one unit at £500..

I bought a second user one for £100 with view to replace..but needs painting and that process potentially damages the ability of the door handle to 'sense' touch..

Current (pun) plan is to remove the door handle and simply disconnect the lead that provides power and gets data from the handle.

There's a second connector for the extended lighting which I'll leave plugged in..

[KennyP]

i did notice your post about the handles on Z4-forum a while ago... was doing my research on them aswell...

im having issues with my door handles aswell... but not that severe as you...

in early spring my drivers door handle did not want to lock with the touch anymore intermittently... mostly it worked, sometimes not... did still open with the touch... passenger side was fine...

Time goes on and things got more severe... now drivers door handle wont lock with a touch at all... once it sprung back to life but then again nothing... passenger door was still all fine...

then i have had 2 times when for a brief moment my door locks went nuts... they repeatedly locked and unlocked the doors 3 times... maybe 4...
First time i was thinking that its my fob doing something in my pocket... but second time i knew it must be that drivers door handle...
After the last time it did that... comfort access locking with the touch has stopped working on both sides... im guessing that repeated lock-unlock stored some sort of error and some module gave up and just switched them off...

i dont think theres any issues with the passenger handle and its just the issue with the drivers handle...

i can still unlock with the touch of the handle both sides... i can use the fob perfectly...i use it all the time to raise or lower the roof... i dont have any power drain issues that are common with the handle failure... also my handles dont feel warm or hot to the touch...
Its basically just the inconvenience of getting the fob from my pocket every time i want to lock the car... i am used to touching those ribs to lock.

I have searched ebay etc for a used one... but finding a used havana brown +lhd +comfort access door handle that also has lighting package led in it... its borderline impossible... too many variables... and if you say painting them will ruin the functionality and you have to find the correct colour... thats likely not going to happen....

Luckily german Hubauershop.de has a discount on my handle (LHD comfort+light) but still they are asking 408 eur painted. No discounts on other handles though... just the fully optioned lhd one...

Anyway purchasing new drivers door handle from them is on my todo list...
Though i could check the wiring aswell... maybe the wires on the back are corroded or shorting...i dont really know... have to get the tool to take the handle off.. that long thing you have to stick in the door.

[Marcoose]

Originally Posted by B21

Comfort access is a number of additional capablities ... You can raise the roof on the fob.

I have comfort access, and I could NOT raise or lower the roof with the fob with the stock programming. I can now, but it required a little reprogramming. I say this in case other people are reading this thinking their comfort access is broken. It's possible it's a US thing.

Originally Posted by B21

The most common failure is the electronics in the door handle (quite complex with a microprocessor) fail..often resulting in an unexplained current drain warning / manin battery going flat if left..

Very interesting. For 4-5 months, I've been dealing with very low battery levels, although without warnings. The reason I know the battery is low is because of the reading on the Schumacher battery tender. (I even bought a second tender to rule out the problem wasn't the tender itself.) I haven't had any problems starting the car, but I top-off the battery at least once a week. It's like something stays on overnight. The battery is less than a year and a half old, and the alternator is two months old. (Albeit the wrong alternator and that's another story hopefully being solved this week.)

Other than temperature, is there a way to diagnose if the handle is kaput ?

Thanks, Peter.

[B21]

Originally Posted by KennyP

i did notice your post about the handles on Z4-forum a while ago... was doing my research on them aswell...

im having issues with my door handles aswell... but not that severe as you...

in early spring my drivers door handle did not want to lock with the touch anymore intermittently... mostly it worked, sometimes not... did still open with the touch... passenger side was fine...

Time goes on and things got more severe... now drivers door handle wont lock with a touch at all... once it sprung back to life but then again nothing... passenger door was still all fine...

then i have had 2 times when for a brief moment my door locks went nuts... they repeatedly locked and unlocked the doors 3 times... maybe 4...
First time i was thinking that its my fob doing something in my pocket... but second time i knew it must be that drivers door handle...
After the last time it did that... comfort access locking with the touch has stopped working on both sides... im guessing that repeated lock-unlock stored some sort of error and some module gave up and just switched them off...

i dont think theres any issues with the passenger handle and its just the issue with the drivers handle...

i can still unlock with the touch of the handle both sides... i can use the fob perfectly...i use it all the time to raise or lower the roof... i dont have any power drain issues that are common with the handle failure... also my handles dont feel warm or hot to the touch...
Its basically just the inconvenience of getting the fob from my pocket every time i want to lock the car... i am used to touching those ribs to lock.

I have searched ebay etc for a used one... but finding a used havana brown +lhd +comfort access door handle that also has lighting package led in it... its borderline impossible... too many variables... and if you say painting them will ruin the functionality and you have to find the correct colour... thats likely not going to happen....

Luckily german Hubauershop.de has a discount on my handle (LHD comfort+light) but still they are asking 408 eur painted. No discounts on other handles though... just the fully optioned lhd one...

Anyway purchasing new drivers door handle from them is on my todo list...
Though i could check the wiring aswell... maybe the wires on the back are corroded or shorting...i dont really know... have to get the tool to take the handle off.. that long thing you have to stick in the door.

I ordered the yellow drivers door from them..they took my money and then a few weeks later said me couldn’t process it..so unless it’s in stock …

Googling indicates a wide range of failure modes including most of yours ….

[B21]

Originally Posted by Marcoose

I have comfort access, and I could NOT raise or lower the roof with the fob with the stock programming. I can now, but it required a little reprogramming. I say this in case other people are reading this thinking their comfort access is broken. It's possible it's a US thing.



Very interesting. For 4-5 months, I've been dealing with very low battery levels, although without warnings. The reason I know the battery is low is because of the reading on the Schumacher battery tender. (I even bought a second tender to rule out the problem wasn't the tender itself.) I haven't had any problems starting the car, but I top-off the battery at least once a week. It's like something stays on overnight. The battery is less than a year and a half old, and the alternator is two months old. (Albeit the wrong alternator and that's another story hopefully being solved this week.)

Other than temperature, is there a way to diagnose if the handle is kaput ?

Thanks, Peter.

I’m not sure if you fired ISTA up and did a specfic test program whether it would show something..

The diagnostic tools showed no errors save current drain from an unspecified location.

My battery is requiring a steady 200ma to maintain charge…if I take the battery off the car it takes 6-7ma..

As I said googling shows many obscure failure modes..in my case if I sit in the drivers seat I can’t stow the roof on the fob..if I sit in the passenger sit I can..albeit slightly jerky…in cabin buttons operate roof both ways no issues..fob doesn’t open roof from either seat nor outside..

It’s quite a complex network of aerials and devices ..I suspect like the CTM it’s quite a dumb device and doesn’t cope well with issues nor gives clear diagnostics..

[Marcoose]

Thanks, Peter. I have an appointment at BMW of San Francisco on Thursday to wrap up the saga of the wrong alternator being installed by an indy. BMW know the alternator saga began with unusual battery levels, and the latter still needs to be solved. I'll ask them to check the handles.

How often are you re-charging your battery ?

Another weird gremlin: In February of 2023, indy #1 installed and registered a new battery. In April of this year, indy #2 said the battery wasn't registered and duly registered it. In May of this year, BMW said the battery wasn't registered. No, there's absolutely no way two indies with more than 50 years of experience between them and perhaps 100 new battery registrations under their belts would fumble both registrations. No way ! Something in the car is un-registering the battery. But that's yet another ballgame.

[Marcoose]

Peter, daft question, if you disconnect the handle (or bypass it), do you still see the same battery discharge ?

[KennyP]

Originally Posted by B21

I ordered the yellow drivers door from them..they took my money and then a few weeks later said me couldn’t process it..so unless it’s in stock …

Googling indicates a wide range of failure modes including most of yours ….

I have ordered parts from them a few times now and they have always delivered... But then again i have never ordered things with a color code from them and thats maybe where the issue is. That yellow is quite rare though.
I will try and order one at some point. Have some more important things to do first. Though as i see this door handle issue can deteriorate even further and can develop into a battery drain for me aswell at some point...

[B21]

Originally Posted by KennyP

I have ordered parts from them a few times now and they have always delivered... But then again i have never ordered things with a color code from them and thats maybe where the issue is. That yellow is quite rare though.
I will try and order one at some point. Have some more important things to do first. Though as i see this door handle issue can deteriorate even further and can develop into a battery drain for me aswell at some point...

If you look on my sites it states that the handle needs to special order to vin to get the colour actioned..they quote 4-6 week lead time..

[B21]

Originally Posted by Marcoose

Peter, daft question, if you disconnect the handle (or bypass it), do you still see the same battery discharge ?

That’s my plan..ordered the materials to be able to access the door lock release mechanism..will advise..

[B21]

Originally Posted by Marcoose

Thanks, Peter. I have an appointment at BMW of San Francisco on Thursday to wrap up the saga of the wrong alternator being installed by an indy. BMW know the alternator saga began with unusual battery levels, and the latter still needs to be solved. I'll ask them to check the handles.

How often are you re-charging your battery ?

Another weird gremlin: In February of 2023, indy #1 installed and registered a new battery. In April of this year, indy #2 said the battery wasn't registered and duly registered it. In May of this year, BMW said the battery wasn't registered. No, there's absolutely no way two indies with more than 50 years of experience between them and perhaps 100 new battery registrations under their belts would fumble both registrations. No way ! Something in the car is un-registering the battery. But that's yet another ballgame.

I’m leaving the battery on constant charge..at 200ma drain in theory I could go 10 days before it was an issue..however when I left it with my Indy to adjust the Ohlins ride height they had it for 8 days and there were several low voltage problems…

Battery registration does seem hit n miss..the IBS sensor could be going bad..I’ve bought a new one as part of this journey..but in this case it wasn’t the issue..

With over 30 ECUs and more than 5 data buses when they get creaky it’s really difficult to bottom issues out..as you’ve noticed.

[Marcoose]

Originally Posted by B21

I’m leaving the battery on constant charge..at 200ma drain in theory I could go 10 days before it was an issue

If you believe the readings of both Schumacher tenders (which is a very good brand), my battery was 100% at 10:30am yesterday, and 55% at 9:30am today. I doubt I can go a week without the tender.

Interesting that the readings from both tenders never exactly match, except 100%. Sometimes the difference can be as high as 10%. And never consistent which is higher or lower. It could be because the new tender is a new model (the old model seems discontinued) and has a different algorithm to calculate battery charge. And I connect the old tender first, then the new tender. It could be that those 5 seconds of 6A charge from the old tender skews the reading for the new tender. I'm going to measure battery charge again tonight and tomorrow before driving to BMW of San Francisco. And another 4-5 times after the proper alternator is installed. For now, it seems the problem isn't the old tender readings. Which is a pity. It would've been great if it was just that.

[B21]

Originally Posted by Marcoose

If you believe the readings of both Schumacher tenders (which is a very good brand), my battery was 100% at 10:30am yesterday, and 55% at 9:30am today. I doubt I can go a week without the tender.

Interesting that the readings from both tenders never exactly match, except 100%. Sometimes the difference can be as high as 10%. And never consistent which is higher or lower. It could be because the new tender is a new model (the old model seems discontinued) and has a different algorithm to calculate battery charge. And I connect the old tender first, then the new tender. It could be that those 5 seconds of 6A charge from the old tender skews the reading for the new tender. I'm going to measure battery charge again tonight and tomorrow before driving to BMW of San Francisco. And another 4-5 times after the proper alternator is installed. For now, it seems the problem isn't the old tender readings. Which is a pity. It would've been great if it was just that.

Well my current drain seems to be accelerating..I put the current monitor on the charger and we are now at 360ma…I’ll see what happens overnight..as soon as the tools arrive I’m going to pop the locks out and remove the comfort access connection..

[Marcoose]

Word from BMW of San Francisco:

Issue #1, (off thread) battery registration: They said the IBS is fine and the battery stayed registered from the last month. They blamed the two indies' equipment. It cannot be. If common folk properly register their batteries at home with commonly-available tools, there's no way the two massively experienced indies don't have the right equipment.

Issue #2, battery drainage: They ran diagnostics and didn't find anything on after shut down. They said the IBS logged battery levels at over 90% during the last 10 days. They said the Schumacher tenders aren't reliable. I don't buy it either. These tenders are reliable. I said if I'm stranded, I'm going to ask for the cost of hauling the car to the dealer and will demand a full reimbursement of the diagnostics. (I bet they'll blame something else and talk their way out of that.)

That's all for now.

[B21]

The current drain has increased up to 360ma so I decided time to act..

I managed to remove the drivers door handle using this video..

I unplugged the power / data lead…set up the CTEK charger up and let the system settle..

Current draw reduced from 360ma to 100ma..the battery unconnected to the car draws 8-10ma on the same basis..

Want to to disconnect the passenger door leads but so far just can’t seem to repeat my success in getting the door handle off..will try again after spraying some PTFE in overnight..

[B21]

So it took about 10 mins to remove the driver door handle..disconnected the power/data feed..current dropped from 360ma to 200ma..

Driver door now stone cold…

It took 5 hours to get the pax door handle off..what a bitch..disconnected that..current now at 76 ma…within the 80ma DM`e current violation threshold…at £500 to fix a handle, given their reliability I’ll pass ..

[KennyP]

no errors or messages after unplugging them?

[B21]

Originally Posted by KennyP

no errors or messages after unplugging them?

I’ve not had any idrive ones..I’ll check with Protool but since it wasn’t recording the burnt out handles I doubt it will change much..will advise..

I think you’d need to use an ISTA test program to ‘find’ an issue..must get round to climbing the learning curve of that product..

[B21]

To conclude after a couple of weeks around Northern Iberia and about 3,000 miles…

No issues or changes with unplugging the leads to the door handle save now no current violation error messages..so all works apart from door handle specific functions ..no error messages..