Hey guys.. Ive started to track my battery levels on the DIC just to see if there is a significant drain going on... and hopefully with as much info as we can get from one another anything can help i suppose...

I started the car last Monday to move it over a little further to the edge of the wall... (We bought a C3 and we needed the room-will post some pics later on)... anyways it started fine the past Mon... I put the cover back on it and it sat for 6 days... I went down today did NOT start the car just checked the battery volts only... it was at 11.7 volts after 6 days of sitting... I know there is a slight drain on the battery when it sits to keep the BCM going... but wondered if that was more than normal for 6 days... I do NOT have relay 46 connected anymore... I will continue to test each day now until i either have to start it and drive it some or hook it up to a charger....thoughts?

 

I just checked mine after 7 days and it is at 12.1 volts. Do you know what it was when you parked it? I have no idea what the expected drain should be after a week.

 

There's alway a slight drain, in the neighborhood of 9-20ma just keeping the computers alive. According to my tech, this should be good for at least 30 days with no use.

My tech did give me a few more tips after I got the car back. He suggested turning off the radio and listening for the sound of the solenoid when the car is turned off. You should hear it if the car shuts down properly. He also suggested making sure everything is turned off, including the rear window defroster if it was used. He has seen cases in GM cars where the defroster continued to drain current even after the car was turned off.

This guy really knows his electronics and, after working on my car for a week, he just shook his head. He doesn't understand why the C6 is so electrically complex when it's supposed to be a performance car. It's a very tough car to figure out when you're trying to diagnose an electrical problem. He said he's certain there's a software bug somewhere in one of the countless circuits that communicate with each other constantly. He's also very sure that GM will eventually find it and issue a fix for it...and, yes, they are aware of the problem. He told me to just drive my car and not worry about it too much. It is, in his opinion, a random bug and one that's not likely to occur again. I told him of the multiple occurences that have been reported and his response was that it can happen, it's just not very likely. No guarantees.

For me, the car will get started and run every week through the winter months even if it doesn't get any further than the garage door.

 

I have also had DBS 2x. One with and 1 w/o #46. The first time w/ #46 it sat for 20 days (hurricanes, business etc.). The 2nd time w/o #46 it sat for 24 hours! The 2nd time I recall the backup lights stayed on at exit, paid no attention 'till StanNH made note in a thread. Now I check the BU lights on exit.

 

If I know I am going to park it for a few days, I just hook it up to a battery tender and forget it, I have it set so its just a plug in at this point, but I do this for my Bike, jet ski batteries and lawn mower as well. Cheap insurance.

I also have an Avalanche, I put an Optima Yellow top in there in 01 and have NEVER had a problem, it sometimes sits for several days. I have had DBS once with the Vette for no reason that I can pin point. I do not do any of the checks that are talked about here on this forum except of course putting it in reverse. This is also with a brand new battery that the dealer put in when they serviced the car one time, they forgot to put it in reverse and drained the battery, they just replaced it as a courtesy.

to sum it up, the battery tender for $50.00 is the best thing you can do except use it as a daily driver (which mine is).

 

The thing I find confusing about relay "46" is that its the same exact part# used for several other functions in the car, there are 3-4 that I counted.So why would one that is not even hooked to anything necessarily be the culprit.I have relay 46 in my car and have left it for 2 weeks and it started right up when I got back.I did have a new battery (upgraded 7 year truck battery) put in and the dealer determined that my radio interface had caused the problem,it interestingly showed a constant 20miliamp draw after shutdown.The stereo place replaced it but said they had never seen one go bad.I have not had another episode since then ,10 months ago.I also run an aftermarket stereo headunit and (3) 220watt alpine power amps.

 

When you are in accessory mode to read the DIC, the battery will read a few tenths of a volt lower than if you hooked a voltmeter to the battery terminals and checked it without it being in accessory mode.

 

Is this something that occurs in 1SB cars only??

I have a 1SA six speed and it sits for WEEKS at a time with no problem in the year plus that I have had it. The car has 5200 miles.

 

You didn't tell me about the C3.

 

You knew I was close... I havent been home too much to stop and share it... gotta chg a few things before the pics go up... its not the one I sent you before... but same RED on RED.. very nice...

 

That's normal as long as the car's not sitting in freezing temps. DBS is not normal. It occurs randomly in MN6 cars, can't be predicted, and can happen to a car even if it was shut down properly. Except for the MN6, there is no common denominator among those of us who have had the honor of experiencing it firsthand. No one has been able to figure this out yet, including GM.

 

Hey Gordon... you are correct it does pull a little more when you do it that way... I dont have the volt meter I need to read the specifics so I do it that way until I can get one...

 

Ok...I thought you were full of hate. Email them to me.

 

I guess this is only a manual shift problem? does it happen on cars that are driven everyday or just the ones that sit?

 

Both.... some may sit a day or 2... when it happened to me it had only sit 4 days... others have been more and less... its a very sporadic issue with minimal clues to follow

 

dont put me in the same category as you... I will get ya some pics soon....