99 Z28 BCM replacement
08-28-2017, 12:56 PM
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99 Z28 BCM replacement I have a 99 Camaro Z28 w/ LS1, 6-speed manny, convertible, that I was just gifted, which is awesome. The not so Awesome part is that I need to undo 5+ years of neglect. I've started on some of the more basic things like replacing the oil, fuel filter, and battery.
However, when she was running she'd occasionally all of the interior lights would cut out. Since all of the powertrain seemed unaffected it was never really addressed. A few years ago I came across a post here and was able to diagnose that it was obviously the BCM (Body Control Module). I know that still needs to be replaced but I wanted to ask y'alls opinion on a few things.
First, when I put in the new battery and hit the key there were all kinds of weird dash lights that came on. I.E. Check Engine, high beams, left turn signal (even thought the turn signal was not on), etc. But, when I hit the ignition nothing from the starter and the high beams turned on.
I was wondering if the BCM could be the cause of the above issue, and cause the starter to not engage or get any power.
Second, when I'm replacing the BCM I've been told that I need to get it "flashed" so that it works in my particular car. Can I buy it pre flashed and/or is the dealership the only place that will definitely be able to "flash" it appropriately?
Sorry for the long first ever post. I appreciate any help or stories that could help me get my girl on the road.
Long live Project Lazarus
However, when she was running she'd occasionally all of the interior lights would cut out. Since all of the powertrain seemed unaffected it was never really addressed. A few years ago I came across a post here and was able to diagnose that it was obviously the BCM (Body Control Module). I know that still needs to be replaced but I wanted to ask y'alls opinion on a few things.
First, when I put in the new battery and hit the key there were all kinds of weird dash lights that came on. I.E. Check Engine, high beams, left turn signal (even thought the turn signal was not on), etc. But, when I hit the ignition nothing from the starter and the high beams turned on.
I was wondering if the BCM could be the cause of the above issue, and cause the starter to not engage or get any power.
Second, when I'm replacing the BCM I've been told that I need to get it "flashed" so that it works in my particular car. Can I buy it pre flashed and/or is the dealership the only place that will definitely be able to "flash" it appropriately?
Sorry for the long first ever post. I appreciate any help or stories that could help me get my girl on the road.
Long live Project Lazarus
08-28-2017, 01:13 PM
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Have you explored the possibility of repairing the original BCM? There are several posts over the years which have illustrated the solder points that usually need to be touched up on the circuit board. Heating/re-soldering these is often all that's needed. This is another option before you move to replacement.
I don't think this would help with the no crank condition though. Lots of things could be going on here, since the car sat for so long and appears to have some electrical concerns. Have wires been chewed by mice? Is there power at the starter relay? This could even be a VATS problem. You could be looking at multiple issues, but you'll have to start tracing where the power is interrupted before you can begin to troubleshoot (that is, assuming the starter itself hasn't failed.)
I don't think this would help with the no crank condition though. Lots of things could be going on here, since the car sat for so long and appears to have some electrical concerns. Have wires been chewed by mice? Is there power at the starter relay? This could even be a VATS problem. You could be looking at multiple issues, but you'll have to start tracing where the power is interrupted before you can begin to troubleshoot (that is, assuming the starter itself hasn't failed.)
08-29-2017, 06:25 AM
#3
Have you explored the possibility of repairing the original BCM? There are several posts over the years which have illustrated the solder points that usually need to be touched up on the circuit board. Heating/re-soldering these is often all that's needed. This is another option before you move to replacement.
The fix is posted in the stickies and even if you aren't in to soldering, this is something that you'll need to get into. Lots of other parts succumb to similar solder joint failures, like the radio, gauge console (less common), and various other control modules.
^ BTW - This solder joint is not unique to these cars. Many cars (like my Toyota truck) of a certain vintage have this type of issue.
08-29-2017, 07:50 AM
#4
The BCM is not related to the CEL, turn signal or headlight circuits so it could not be the cause of your dash warning lights. The only dash lights it manages are the seat belt, security, and alarm LED. The VATS in the BCM could be the cause of the starter failing to engage but not the high beams going on. If VATS is activated, the SECURITY warning light in the instrument cluster will be either on steady or flashing.
To answer your second question... it depends on whether you get a new/remanufactured BCM or a used one. The BCM is self-programming when new or reman. Install it, insert your ignition key, turn on the ignition and it will program itself to that key. No need to get the dealer to do anything.
However, the BCM can only be programmed once and never reprogrammed, so if you get a used one you'll have to match your key to the value already programmed in that BCM. The easiest way is to get the original key that went with the BCM. Otherwise, you have 14 different possible values to try until you find the one that works.
To answer your second question... it depends on whether you get a new/remanufactured BCM or a used one. The BCM is self-programming when new or reman. Install it, insert your ignition key, turn on the ignition and it will program itself to that key. No need to get the dealer to do anything.
However, the BCM can only be programmed once and never reprogrammed, so if you get a used one you'll have to match your key to the value already programmed in that BCM. The easiest way is to get the original key that went with the BCM. Otherwise, you have 14 different possible values to try until you find the one that works.