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Bcm issue

yz300

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Hi everyone. I.ve got an 03 vy berlina sedan. I had srs, abs, aircon and trac control alarms going off like mad and often the buttons on the key don.t unlock the doors or boot, so i took it to the mechanic. After quite a bit of money and buying an ecu/bcm/key combo from the wrecker to keep costs down and replacing burnt relays he thought he.s solved the problem. He said his scan gun said no communication from bcm. It was awesome, until today. I put the key in and before i.d even started it i had all those alarms come up again except the aircon, the door lock buttons on the key weren.t working properly either until i pulled the bcm fuse (the 10amp one under the bonnet) and put it back in. I heard a noise and thought hmmmm. Put the key back in and no codes. Could this be as simple as replacing the key battery or could it be a dicky wire from the bcm to its fuse or the bcm to the ecu? Is there anything else it could be? Input will be appreciated, thanks Gus.
 

krusing

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It sounds like either a Alternator issue, like over voltage.
or earthing issue with all the symptoms happing all at the same time, I read somewhere there is a Earth terminal that can come lose, near the alternator, and/or adjacent the BMC.
Where he said no communications from the BCM, was he unable to read any codes at all ?
I see your in Victoria, but where ?,
Because there maybe some close by that is a member of JC's that maybe able to help.

PS: I helped another JC's member Nealeyboy not long ago with a similar issue, and it was a Alternator issue,
If you in close proximity to me, I will PM you.
 
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yz300

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It sounds like either a Alternator issue, like over voltage.
or earthing issue with all the symptoms happing all at the same time, I read somewhere there is a Earth terminal that can come lose, near the alternator, and/or adjacent the BMC.
Where he said no communications from the BCM, was he unable to read any codes at all ?
I see your in Victoria, but where ?,
Because there maybe some close by that is a member of JC's that maybe able to help.

PS: I helped another JC's member Nealeyboy not long ago with a similar issue, and it was a Alternator issue,
If you in close proximity to me, I will PM you.
Wow thanks for the detailed reply. I think he was able to see other codes but loss of communication with everything it.s meant to came up too. Even when the car is off and i try to unlock the doors with the buttons it sometimes doesn.t work properly, just incase this might mean something. I live in corio, near geelong. Thanks again hey!!
 

Trevor loves holden.

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Try pulling off the ABS connector then see if it fixes the problem. Doesn't sound like a mechanic job more like a auto electrician. Check all your earth wires around the battery to chassis, test your battery voltage with it running with a multimeter.
 

yz300

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Try pulling off the ABS connector then see if it fixes the problem. Doesn't sound like a mechanic job more like a auto electrician. Check all your earth wires around the battery to chassis, test your battery voltage with it running with a multimeter.
Thanks for your reply,
What.s the highest voltage it should be?
 

Trevor loves holden.

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Thanks for your reply,
What.s the highest voltage it should be?
Any where from 13.8 to 14.2 no higher than 14.8. Like was said if not your Alternator try removing your ABS harness under the hood see if that sorts things out.
 

yz300

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Any where from 13.8 to 14.2 no higher than 14.8. Like was said if not your Alternator try removing your ABS harness under the hood see if that sorts things out.

Hi thanks again for your reply. Can you tell me where the abs harness is by any chance? I think i saw it and had a little try the other day but couldn.t work out how to do it without breaking it? Gus.
 
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