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Discussion Starter #1
There are quite a few threads on this problem where when your Solstice is sitting for a few days, the battery is drained. I did not find any definitive conclusions on why this problem happens. I have had this problem for the last two years. If I let the car sit more than 3 days w/o being driven, the battery will be drained. I can usually jump start it and if I drive it daily, I won't have this problem. I have gone through 3 brand new batteries the last two years (the cells go out if you ignore this problem). The very first time this happened, the head unit was toast. Burned out. It took a while but I eventually replaced it with a Pioneer unit. Not sure if this is in any way related but is it the only other change that has happened since this problem appeared. The symptoms were identical with the burned out head unit or the Pioneer head unit

I have done some measurements by hooking a good quality ammeter in series with the battery. When the connection is first established, the draw will be around 720mA (milliamps). It will quickly drop to around 450mA, then down to 300mA where it will hover for a while and then it will settle down to 150mA (steady state). I have done both sets of measurements with the alternator connected/disconnected. No difference. The other possibility of drainage would be the starter, I suppose, but have not tested that yet.

I subsequently went through every single fuse, relay and the single diode (WPR diode) in the fuse box and none made any difference in the parasitic drain whatsoever by removing them *except* for the 50A BCM fuse (fuse #7). Once that was removed, the drain went away. So, in essence, it appears that the BCM needs 150mA at all times which is ludicrous. As a comparison (which is not great but mentioned nevertheless) my 93 chevy truck only draws about 9mA in steady state.

Is this a fact that I need to accept and use a trickle charger henceforth? I can see the battery becoming marginal after a few weeks of inactivity but not after a few days.... and no, my batteries have been brand new, not marginal. Again, I did not have this problem the first 5 years of ownership. Driving habits have not changed. I cycle through all the vehicles in my arsenal that is why all of them will have down time that extends into several days....
 

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Since you have probably read the threads on this subject, the following is old news. But for completeness. . .

When the car is "off" its never truely powered down. Most of the car is fly by wire and events are triggered via one of the data busses. In order for the car to know when to "start" the BCM has to be actively listening, the buss has to be powered up and the sensors that can trigger the start up events have to be active. So yes the BCM never powers down.

Since yours is an early VIN it has a different set of hardware from my 07 and 08 cars. My experience is that as long as I start the cars at least once a month, they are fine. I have never had a battery go totally dead so far. I do have trickle chargers on my Harley and have one I could use on the cars but have not had the need to do so since bringing them home in 2007. I did replace the factory battery in my Sol this summer with a red top but the old one is still around and still holds a charge. It was just its time.

The simple fix is to add a trickle charger with the safety plug and call it good.
 

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I found that discontinuing OnStar service tripled my drain down time.

OnStar apparently sucks in more than one sense.
 

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I found that discontinuing OnStar service tripled my drain down time.

OnStar apparently sucks in more than one sense.
Agreed, I was just about to ask the OP if he had OnStar. I got it free for a year when I first got the car, and the first winter, I already noticed hard starts in the winter. After the first year ran out, and I removed some OS equipment since I knew I was never going to use OS after the free year. The car started easier the following 2 years on the same battery.
 

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We have onstar on the Sky and it is fine as far as battery life is concerned. I am sure it is drawing more than the non-OS car but it still goes a month between charges just fine.:thumbs:
 

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I have the same issue with battery drain. It was fine for years then became intermittent and now has a consistent drain problem. I am thinking of using this device to solve the problem.
Priority Start Battery Protector - Corvette Parts and Accessories
This takes your battery out of the loop for $110. You can manually disconnect the battery for free. Its easy and quick. I have done it many times with Punisher as part of the tuning process. I would think getting a trickle charger / battery tender for half that price and leaving the BCM powered up would be a preferable solution.
 

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I have done some measurements by hooking a good quality ammeter in series with the battery. When the connection is first established, the draw will be around 720mA (milliamps). It will quickly drop to around 450mA, then down to 300mA where it will hover for a while and then it will settle down to 150mA (steady state). I have done both sets of measurements with the alternator connected/disconnected. No difference. The other possibility of drainage would be the starter, I suppose, but have not tested that yet.
Your measurements to that point, are completely normal. Please note, however, that the Car will go into a 'sleep' mode after ~20 minutes. From then on, you should see a draw of single digit mA's. You should continue your drain tests for at least 30mins and check if something's preventing the BCM from 'sleeping'.

See the following post and then read on... mirror leds, post #9

(especially post #14 ...and then my measurements at post #18)
 

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Discussion Starter #10
Your measurements to that point, are completely normal. Please note, however, that the Car will go into a 'sleep' mode after ~20 minutes. From then on, you should see a draw of single digit mA's. You should continue your drain tests for at least 30mins and check if something's preventing the BCM from 'sleeping'.

See the following post and then read on... mirror leds, post #9

(especially post #14 ...and then my measurements at post #18)
Thanx Tomato for this post and all the others that have chimed in. I have been running tests all afternoon. It looks like, if there is a BCM sleep mode, my BCM never achieves it. I let it sit there for about 40 minutes + and the drain will not go below 150mA.

BTW, my Sol did not come with OnStar.

Now the question is, what would prevent the BCM from reaching sleep mode?
 

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Well, first, you did close the doors, turn the ignition off, etc, right?

If so, I'd pull the radio connectors and check that it's not the culprit.
 

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You said that you pulled all of the fuses, obviously referring to the ones in the underhood fuse block. What about the individual fuses in the BCM ? There are a number of smaller fuses downstream of the that one you said stopped the current flow.
 

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I am taking note of the battery drain issue. It is respected if you're a DIY kind of person but if you're not able to resolve, a dealership should be able to properly handle this situation. If you decide to take it in, please send a DM with your VIN#, name, situation, and contact information. I hope everyone's concerns are resolved quickly. Have a great New Year!

Matt,

GM Customer Assistance
 

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I am taking note of the battery drain issue. It is respected if you're a DIY kind of person but if you're not able to resolve, a dealership should be able to properly handle this situation. If you decide to take it in, please send a DM with your VIN#, name, situation, and contact information. I hope everyone's concerns are resolved quickly. Have a great New Year!

Matt,

GM Customer Assistance
The challenge is that most dealers really dont have experience with this car and have historically "not been able to reproduce" or "its normal behavior" and there is no repair applied.
 

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The challenge is that most dealers really dont have experience with this car and have historically "not been able to reproduce" or "its normal behavior" and there is no repair applied.
Also there are mechanic's that don't know how to check for a drain on your battery. A couple I know have been a mechanic for years. My step daughter bought a used Honda for her son. After a few days the battery would not start it. The battery was a few years old so it was changed. They had the battery go dead again after a fews days. They took I to shop and they could not fine anything wrong. Even took it to a uncle who works o cars could not find the problem. As long as the car was driven a lot they would not have a issue. I keep telling them something is draining the battery did any one check for that. Finally got them to bring it to me. It was really easy to find the drain when the battery was disconnected and reconnected you hear the AC clutch clicking every time.

Don
 

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Discussion Starter #16
Battery Drain Source Found

You said that you pulled all of the fuses, obviously referring to the ones in the underhood fuse block. What about the individual fuses in the BCM ? There are a number of smaller fuses downstream of the that one you said stopped the current flow.
Thank you! I had not checked those fuses. So, what I did this morning is open both doors, removed fuse #27 which is the interior lights fuse, hooked up my ammeter and waited patiently until the draw was down to 150mA which is the steady state for this car. Started pulling fuses and long and behold I found it. When I remove fuse #23, the draw goes down to 14mA, which is very reasonable. Fuse #23 is the.....

radio.

I have an aftermarket head unit that I installed not so long ago. It is a Pioneer AVH-P4400BH. I guess now that I have something to work with, my research will switch to this particular unit. There may not be much I'll be able to do there so may be a permanent, easily accessible trickle charge hook up will be something I will have to live with...


Thanx all for your thoughts.
 

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Excellent info and great find! Though I've not had any problems with the issue, this is the kind of nugget you like to store in the back of your skull in case the problem shows up again.

Doesn't sound like the Pioneer should still be drawing that much. Definitely let us know if you find something with the unit or it's install that can be changed.

If not, here's a decent trickle charger. It can be mounted under the hood and left in place - just plug it in when the car is parked. I personally do NOT have this unit permanently mounted - I got it at about half price on sale at a local hardware store and changed the ends to clamp style terminals and use it on my generator battery.

http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_1-5-amp-12-volt-trickle-charger-maintainer-schumacher_9200012-p?searchTerm=trickle+charger
 

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For What It's Worth

It seems that this battery drain happens more often with the GXPs and Redlines than with NAs.

It also appears to happen more frequently on the cars with Onstar than the ones without (realizing that there aren't that many that don't have Onstar).

:dunno:
 

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