Battery Safety Terminal Bypass
#31
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My Ride: bmw 525d m sport auto e60
hi, i have a e60 525d m sport with the airbag light on, have done the diagnostic and its the battery safety terminal
and the seat mat occupancy sensor ..(i know this part needs to be dealt with seperatly)
ive seen your pics but am a little confused as to where to cut wire from exactly
and secondly when you say test the bst...how do i do that with a voltage meter ..where do stick it in to read?
sorry to sound amateur but ive never fiddled with car electronics much although am good mechanically.
and the seat mat occupancy sensor ..(i know this part needs to be dealt with seperatly)
ive seen your pics but am a little confused as to where to cut wire from exactly
and secondly when you say test the bst...how do i do that with a voltage meter ..where do stick it in to read?
sorry to sound amateur but ive never fiddled with car electronics much although am good mechanically.
Last edited by bmwm-power; 10-19-2014 at 03:31 AM.
#32
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My Ride: bmw 525d m sport auto e60
hi, i bought 2x 1ohm resisters and soldered them in line
i cut the two black bst wires and then wired the resistor to the 'car' side of the cable that i cut. i tried to delete the code but it doesnt go away ..
any tips the resistors i soldered together measure 2.8 ohm approx on a digital ohm meter and they are 2w each
can u tell me where i may have gone wrong
After chopping the two black wires i tested the 'BST' side of the two wires to measure the resistance and it was coming back as 3ohm. so the bst is putting out 3ohm resistance, does that mean i should just add a 10hm resistor in parallel instead without chopping wires from bst
here is a little diagram ive drawn from my understanding of this
thanks
i cut the two black bst wires and then wired the resistor to the 'car' side of the cable that i cut. i tried to delete the code but it doesnt go away ..
any tips the resistors i soldered together measure 2.8 ohm approx on a digital ohm meter and they are 2w each
can u tell me where i may have gone wrong
After chopping the two black wires i tested the 'BST' side of the two wires to measure the resistance and it was coming back as 3ohm. so the bst is putting out 3ohm resistance, does that mean i should just add a 10hm resistor in parallel instead without chopping wires from bst
here is a little diagram ive drawn from my understanding of this
thanks
Last edited by bmwm-power; 11-07-2014 at 01:44 AM.
#35
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My Ride: bmw 525d m sport auto e60
i tried connecting chopping the two black wires coming off the bst and connecting 2x 1ohm resistors inline but that didnt work
then i tried the other suggestion of leaving them connected to the bst and instead just adding a 10hm resistor in parallel but that didnt work either
the code on my diagnostic is 93b2 bst
I read on another forum that there two pins under the plastic casing which are there to prevent static discharge and these could be earthing hence throwing up a code so im going to check this next
mbarratt..if you chop the two wires from the battery then the two that are coming from battery just tape up so they dont contact anything. the resistor goes on the 'car' side of the circuit to mimic the resistor that would normally be present from bst
then i tried the other suggestion of leaving them connected to the bst and instead just adding a 10hm resistor in parallel but that didnt work either
the code on my diagnostic is 93b2 bst
I read on another forum that there two pins under the plastic casing which are there to prevent static discharge and these could be earthing hence throwing up a code so im going to check this next
mbarratt..if you chop the two wires from the battery then the two that are coming from battery just tape up so they dont contact anything. the resistor goes on the 'car' side of the circuit to mimic the resistor that would normally be present from bst
#36
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My Ride: 2003 BMW 525i Touring
Hi, how you folks doing, Im new to this site and to the BMW world, just a week ago I bought a 2005 BMW 545i and when I got it, she was running like a champ. Then out of the blue she decided to give me an airbag light. To say the least, I was pissed and was wondering what caused it. My brother works at a Chevy stealership and he has a scan tool for BMWs, so we hooked it up and the error code was 9aff. After some searching on the internet and figuring out what it was, I found the Z3 deleting BST thread on bimmerfest.com. I used that as a guild and made my own DIY mod. I would like to share the bypass or delete of the BST if you would like to save yourself money and the hassel of the stealership. This works, no airbag light for me anymore. All that is needed is a 2 ohm resistor and a soldering iron. Just cut the two black wire and place the resistor inline of the BST. Next tuck the wires away neatly and have the computer cleared of the airbag light and it should be good to go.
same problem, but does the 2008 528i have this BST ? I will take a picture of the battery and check if it has this BST, thanks
#37
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My Ride: bmw 525d m sport auto e60
another update..
issue resolved
car : late 2005 55 e60 525d m sport auto
problem: seatbelt/airbag light on
fault code on diagnosis: 93b2 safety battery terminal
solution...
i cut the two black wires coming out of the bst and connected two 1ohm resistors in line (reason for using 2x1ohm is because i couldnt find a single 2ohm!) so a single 2 ohm will work aswell. I tested the resistance of these before fitting and it was approx 2.7ohm total.
The reason it didnt work the first time i tried it as in my previous post is that i was trying to reset /delete the code whilst car was running...it has to be reset when ignition is on and not with engine running.
many thanks to the original poster for the tip. Thought id share my version of this as its a very common issue.
issue resolved
car : late 2005 55 e60 525d m sport auto
problem: seatbelt/airbag light on
fault code on diagnosis: 93b2 safety battery terminal
solution...
i cut the two black wires coming out of the bst and connected two 1ohm resistors in line (reason for using 2x1ohm is because i couldnt find a single 2ohm!) so a single 2 ohm will work aswell. I tested the resistance of these before fitting and it was approx 2.7ohm total.
The reason it didnt work the first time i tried it as in my previous post is that i was trying to reset /delete the code whilst car was running...it has to be reset when ignition is on and not with engine running.
many thanks to the original poster for the tip. Thought id share my version of this as its a very common issue.
Last edited by bmwm-power; 11-26-2014 at 02:16 AM.
#38
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My Ride: Sold: 545i, sport package, cold weather, 6MT
Model Year: 2004
Engine: N62
I replaced my BST cable and it was quite easy. The cable itself was about $250 and it took about a half hour to install.This is certainly a better option than the $1100 quote or messing with your airbag system.
#39
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My Ride: bmw e60 msport
Model Year: E60
Engine: 2.5
airbag light
I had exactly the same problem and it failed the MOT (I'm in the UK) because the airbag light was on. I followed this guide but could only buy either 1 ohm or 2.7 ohm resistors (from Maplins) so i bought 2 x 1 ohm resistors and wired them together in series - took me 10 mins and its all sorted... I know this is an old thread but thank you , thank you, thank you!!!!
Cheers
Barry
Cheers
Barry