Parasitic Battery drain, Start Button stays illuminated always.. CAS?

TheyH8n · 07-20-2019, 12:09 PM

Hello just bought the car a week or so again have had the increased battery discharge a couple times when starting the car. Last night I noticed the start/stop button light does not goes off. Not after 16 minutes not after 6hours. From my research it seems the CAS module controls the start button? I do NOT HAVE CA I don’t know where to go or what to replace at this point. I’m really on the fence about selling the car from all I’ve read with all their electronics they seem highly unreliable long term. I do enjoy driving the car but am not looking for a money/time pit. I’ve read things from headunit replacement to IBS but not a lot surround my exact issue. I do have the IBS unhooked right now.. it made no difference

Sensible_ · 07-21-2019, 03:56 AM

Quote:

Originally Posted by TheyH8n

Hello just bought the car a week or so again have had the increased battery discharge a couple times when starting the car. Last night I noticed the start/stop button light does not goes off. Not after 16 minutes not after 6hours. From my research it seems the CAS module controls the start button? I do NOT HAVE CA I don’t know where to go or what to replace at this point. I’m really on the fence about selling the car from all I’ve read with all their electronics they seem highly unreliable long term. I do enjoy driving the car but am not looking for a money/time pit. I’ve read things from headunit replacement to IBS but not a lot surround my exact issue. I do have the IBS unhooked right now.. it made no difference

Battery drains can be tricky to diagnose.

Start with fault codes. Are there any?

ctuna · 07-21-2019, 01:42 PM

The electronics are not usually a big problem with these or any
cars of a similar year. The IBS can be confusing.
You need to get diagnositcs up and going to stand a chance of fixing
this.

electical e90 pdf
http://www.google.com/url?sa=t&rct=j...,d.cGU&cad=rja
http://www.google.com/url?sa=t&rct=j...85464276,d.cGU
http://www.google.com/url?sa=t&rct=j...85464276,d.cGU

TheyH8n · 07-22-2019, 02:34 PM

Quote:

Originally Posted by ctuna

The electronics are not usually a big problem with these or any
cars of a similar year. The IBS can be confusing.
You need to get diagnositcs up and going to stand a chance of fixing
this.

electical e90 pdf
http://www.google.com/url?sa=t&rct=j...,d.cGU&cad=rja
http://www.google.com/url?sa=t&rct=j...85464276,d.cGU
http://www.google.com/url?sa=t&rct=j...85464276,d.cGU

thanks for links also seen them in another thread you posted in while i was researching.. next thing for me to do is an amp draw test and pull fuses. im pretty sure its going to be the start/stop switch and/or the CAS module though which controls it

MACKENZIE2576 · 09-13-2020, 08:53 AM

Did you find out the problem?

Runnin'Rich · 09-18-2020, 09:19 PM

When my JBE was in program status 12 due to failing to flash with a faulty cable I too had the light on the start button not turn off.
I think maybe there is a lack of communication between some of the modules on your car. Get a DCAN cable and read the UIF in INPA and see if all the modules are listed. Check for errors on all modules

07-20-2019, 12:09 PM	#1
TheyH8n Private First Class 25 Rep 173 Posts Drives: 335i e93 Join Date: Jul 2012 Location: Indio CA iTrader: (0)	Parasitic Battery drain, Start Button stays illuminated always.. CAS? Hello just bought the car a week or so again have had the increased battery discharge a couple times when starting the car. Last night I noticed the start/stop button light does not goes off. Not after 16 minutes not after 6hours. From my research it seems the CAS module controls the start button? I do NOT HAVE CA I don’t know where to go or what to replace at this point. I’m really on the fence about selling the car from all I’ve read with all their electronics they seem highly unreliable long term. I do enjoy driving the car but am not looking for a money/time pit. I’ve read things from headunit replacement to IBS but not a lot surround my exact issue. I do have the IBS unhooked right now.. it made no difference
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07-21-2019, 01:42 PM	#3
ctuna Lieutenant General 1911 Rep 13,103 Posts Drives: 325xi 06 wagon MT Join Date: Jan 2010 Location: Santa Cruz, Ca iTrader: (0)	The electronics are not usually a big problem with these or any cars of a similar year. The IBS can be confusing. You need to get diagnositcs up and going to stand a chance of fixing this. electical e90 pdf http://www.google.com/url?sa=t&rct=j...,d.cGU&cad=rja http://www.google.com/url?sa=t&rct=j...85464276,d.cGU http://www.google.com/url?sa=t&rct=j...85464276,d.cGU
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09-13-2020, 08:53 AM	#5
MACKENZIE2576 Enlisted Member 6 Rep 43 Posts Drives: Bmw e90 LCI Join Date: Jul 2020 Location: Leicester iTrader: (0)	Did you find out the problem?
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09-18-2020, 09:19 PM	#6
Runnin'Rich Private First Class 90 Rep 148 Posts Drives: 2009MY E91 328Xi 6MT Join Date: Sep 2020 Location: British Columbia Canada iTrader: (0)	When my JBE was in program status 12 due to failing to flash with a faulty cable I too had the light on the start button not turn off. I think maybe there is a lack of communication between some of the modules on your car. Get a DCAN cable and read the UIF in INPA and see if all the modules are listed. Check for errors on all modules
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