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lesage
11-08-2005, 11:12 AM
BMW battery new 3/04 75ampHr seemed not to hold charge. take to BMW to claim under warranty

Report was that battery was OK - It was "severly discharged" when they first got it--73% --they charged it overnite and reported 86% charged next morning and they rated the battery as OK- However they detected a current drain of .18a on circuits controlled by Fuse 20 (have since confirmed this w/my own reading on a DMM, at .19a).

Fuse 20 is stated to control:-
a/c
CC module
Clock
Heater control
Instrument cluster
OBC

Removing Fuse 20 cuts the drain to within Shoguns limits-- .06a dropping down to .03a
QUESTIONS:
1
Does anyone have any suggestions on how I can go about testing stuff on Fuse 20 circuits?
2
Have noticed following immediately on reconnecting battery (or when testing for the leak using DMM set for a '<10A' measurement :

I can hear a relay click. It seems to be the small black one to the left and one up from the big LKM. and

The right and left turn indicators make a single "hazard warning" style flash on the dashboard. I presume all this is normal and has nothing to do with the drain. (removing that relay doesnt reduce the .18 drain) ...any views?
3
When driving back from the dealer I noticed that A/c and recirc seemed dead. I have had that before after I changed microfilter & it turned out to be my crappy reinsertion of the plugs into sockets behind the sword type thing. I wonder if my imperfections in this area are causing the present problems...? I havent investigated all this yet but will do tomorrow.
4
Is a drain of .18a, .19a ALL that significant...? The eyewatering cost of BMW Heathrows tests woudve bought me 2 new BMW batteries...and Im just wondering if in REAL life one does simply wear a modest drain, put it down to it being like the poor... and just replace the damn battery...BMW say the batt is OK - it gets them off a warranty claim. But in real life itd be cheaper just to replace it if a decent new battery would tolerate such a drain if thats relatively modest...crude, no doubt, but more practical...and ultimately cheaper?
Advice/ Views appreciated :)
Bill R.
11-08-2005, 11:27 AM
Obc
Ihkr
Park ventilation mode
Zke interior lights control
Park , tail , underhood lights
Instrument cluster, check control module
Eml throttle control

Given the choices here, I would first choose the obvious such as the underhood light staying on all the time or the glovebox light staying on, I would check there first.








BMW battery new 3/04 75ampHr seemed not to hold charge. take to BMW to claim under warranty

Report was that battery was OK - It was "severly discharged" when they first got it--73% --they charged it overnite and reported 86% charged next morning and they rated the battery as OK- However they detected a current drain of .18a on circuits controlled by Fuse 20 (have since confirmed this w/my own reading on a DMM, at .19a).

Fuse 20 is stated to control:-
a/c
CC module
Clock
Heater control
Instrument cluster
OBC

Removing Fuse 20 cuts the drain to within Shoguns limits-- .06a dropping down to .03a
QUESTIONS:
1
Does anyone have any suggestions on how I can go about testing stuff on Fuse 20 circuits?
2
Have noticed following immediately on reconnecting battery (or when testing for the leak using DMM set for a '<10A' measurement :

I can hear a relay click. It seems to be the small black one to the left and one up from the big LKM. and

The right and left turn indicators make a single "hazard warning" style flash on the dashboard. I presume all this is normal and has nothing to do with the drain. (removing that relay doesnt reduce the .18 drain) ...any views?
3
When driving back from the dealer I noticed that A/c and recirc seemed dead. I have had that before after I changed microfilter & it turned out to be my crappy reinsertion of the plugs into sockets behind the sword type thing. I wonder if my imperfections in this area are causing the present problems...? I havent investigated all this yet but will do tomorrow.
4
Is a drain of .18a, .19a ALL that significant...? The eyewatering cost of BMW Heathrows tests woudve bought me 2 new BMW batteries...and Im just wondering if in REAL life one does simply wear a modest drain, put it down to it being like the poor... and just replace the damn battery...BMW say the batt is OK - it gets them off a warranty claim. But in real life itd be cheaper just to replace it if a decent new battery would tolerate such a drain if thats relatively modest...crude, no doubt, but more practical...and ultimately cheaper?
Advice/ Views appreciated :)
lesage
11-08-2005, 12:41 PM
Bill: on mine, the glovebox light anly operates when ignition is on so cannot contribute to a 'parking' drain. And I dont have an underhood light...
Traian
11-08-2005, 02:34 PM
I had a somewhat similar problem with my car. Battery would die overnight sometimes, and hold charge badly. ONe of the fuses (I believe it was 20) showed a rather large voltage across it with the key out of the ignition, but was not shorted (resistance was inf). In the end I replaced the battery and it ran like a peach. Note: I also abused my battery in the last few months, it died quite a few times as a result of the alarm running continuously (other problem), so this would have accelerated its demise - Note sure what could have caused your battery to die so soon.

One thing I noticed is that if all the dash/computer lights appear dim with the key in the ignition but brighten up when the engine is running and power comes from the charging system, your battery is at fault.
Traian
11-08-2005, 02:35 PM
One more idea: Run the car a good while to get the battery up to charge, park it, take out your suspect fuse, leave it for the night/day/week/... and see if your battery is still weak when you return.
lesage
11-08-2005, 03:28 PM
One more idea: Run the car a good while to get the battery up to charge, park it, take out your suspect fuse, leave it for the night/day/week/... and see if your battery is still weak when you return.

yes your pragmatism appeals. meanwhile I have disconnected battery and put it on a low charge. Will see if it can stand a weeks lying around after that. Have feeling that if its not my imperfectly reseating the connectors on the Sword thing, then a new battery is probaby cheaper & easier solution...
Bill R.
11-08-2005, 04:34 PM
closed circuit current which is 40 milliamps on the e34..http://www.bimmernut.com/%7Ebillr/images/closedcurrentlatercars.jpg





Bill: on mine, the glovebox light anly operates when ignition is on so cannot contribute to a 'parking' drain. And I dont have an underhood light...
lesage
11-09-2005, 02:47 AM
Bill: thanks for that. Yes, am trying to measure drain by connecting wands on the DMM to -ve battery lead and -ve battery terminal and measuring amps. Dont have those wonderfully sophisticated BMW bits in your extract. However what Ive failed to do, which your extract reminds me to, is to operate central locking when Im inside car trying to hold leads in place...
Will make more measurements this am.
Meanwhile battery now nicely charged with the hydrometer-type signal on its little top showing green at last
lesage
11-09-2005, 01:01 PM
Bill: what does "Zke interior lights control" refer to? assuming its a relay, do you know where it is?
And where are relays for Ihkr (I assume that the 'manual automatic' not fully automatic Climate control...)?