'05 C6 battery issues
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'05 C6 battery issues
Hey guys, I have a 2005 C6 and have been having terrible battery issues. At first, my car would randomly not start sporadically. I'd have to break into the car via the trunk, only to find that some of the electronics like the heat and air worked, but the car wouldn't start. After getting stuck at work multiple times, I eventually got the battery replaced, and everything was fine.
This morning, I walked up to my car, started it, and began to drive away. However, I forgot I left something at my house and drove back. I parked the car outside my house, still running, ran inside to grab what I had forgotten, and came back out. I noticed that as I had gotten back in the car, I couldn't put my window back up (I had rolled it down). I then noticed that all of my dials flashed up and down (like gas, battery, etc). The radio would not work either, but at this point the car was still on and drivable. I turned the car off to try and restart it, which I was able to do. However, this time, all those problems came immediately. Also, even though the car started, my transition was locked in park and I could not move the car. I think quickly turned the car off, which looks like it went back into accessory mode, which I turned off.
Now I can't start my car and it seems as if its the same exact problem I had before. Could this be because the car was running while I ran into my house with the key fob with me? I don't know what's wrong with my car or why it is doing this. I literally just got a brand new battery put in a few weeks ago. Thanks for your time guys.
This morning, I walked up to my car, started it, and began to drive away. However, I forgot I left something at my house and drove back. I parked the car outside my house, still running, ran inside to grab what I had forgotten, and came back out. I noticed that as I had gotten back in the car, I couldn't put my window back up (I had rolled it down). I then noticed that all of my dials flashed up and down (like gas, battery, etc). The radio would not work either, but at this point the car was still on and drivable. I turned the car off to try and restart it, which I was able to do. However, this time, all those problems came immediately. Also, even though the car started, my transition was locked in park and I could not move the car. I think quickly turned the car off, which looks like it went back into accessory mode, which I turned off.
Now I can't start my car and it seems as if its the same exact problem I had before. Could this be because the car was running while I ran into my house with the key fob with me? I don't know what's wrong with my car or why it is doing this. I literally just got a brand new battery put in a few weeks ago. Thanks for your time guys.
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Update: guys I just got the battery tested by triple A; the battery was at 100% capacity but was not cranking any amps.
could this have anything to do with me leaving the car running while taking the key fob with me? or no?
What should I do?
could this have anything to do with me leaving the car running while taking the key fob with me? or no?
What should I do?
Race Director
Joined: Mar 2010
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From: T-Town WA
2016 C6 of Year Finalist
Also, for ***** and giggles, replace the FOB battery
Race Director
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Leaving the car wouldn't have anything to do with it. Sounds like you just need to return the new battery and get a new one. I'd have the new one load tested before installing it just to make sure it's good.
Drifting
Joined: Sep 2014
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From: Atlanta - - - - - Save the manuals
I don't know if this is your problem, but my '05 experience is as follows.
I had the same problem as you on and off and I could not get the positive cable, IIRC, to stay tight. Fast Forward a few years, and I needed a new battery.
It seems the 05 battery has the +/- posts reversed from all the other c6's. Since the +/- battery posts are not the same size you will always have a bad connection to the car with the results matching your problem. So make sure that the battery is not for a 2006+ corvette. The 05, at least mine, has the positive terminal closest to the fender.
I had the same problem as you on and off and I could not get the positive cable, IIRC, to stay tight. Fast Forward a few years, and I needed a new battery.
It seems the 05 battery has the +/- posts reversed from all the other c6's. Since the +/- battery posts are not the same size you will always have a bad connection to the car with the results matching your problem. So make sure that the battery is not for a 2006+ corvette. The 05, at least mine, has the positive terminal closest to the fender.
Last edited by Dutch08; Jan 28, 2020 at 11:32 AM.
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Race Director
Joined: Mar 2010
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From: T-Town WA
2016 C6 of Year Finalist
Try disconnecting your positive cable for a couple minutes the reconnect.
When you say no start is everything dead? Did you try the FOB in the slot in the glove box?
Safety Car
Joined: May 2011
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From: Oshawa, Ontario
To get it into neutral press on the start button without stepping on brake pedal.Next press and hold bottom of start button for 30 seconds or so until gauges light up and you will be able to scroll through DIC.When you can scroll through DIC you will now be in accessory mode.Press brake pedal and you will now be able to shift into neutral
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yes , I tried the key fob in the slot under the passengers dash. Didn’t work. Some things work, like I noticed the windows automatically going up when trying to unlock the passenger door (but doesn’t open). The green light on the push to start turns on when I open the door manually. The red security light flashes when I try to open the door. those are the only things I can think of that are working
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To get it into neutral press on the start button without stepping on brake pedal.Next press and hold bottom of start button for 30 seconds or so until gauges light up and you will be able to scroll through DIC.When you can scroll through DIC you will now be in accessory mode.Press brake pedal and you will now be able to shift into neutral
Thread Starter
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I don't know if this is your problem, but my '05 experience is as follows.
I had the same problem as you on and off and I could not get the positive cable, IIRC, to stay tight. Fast Forward a few years, and I needed a new battery.
It seems the 05 battery has the +/- posts reversed from all the other c6's. Since the +/- battery posts are not the same size you will always have a bad connection to the car with the results matching your problem. So make sure that the battery is not for a 2006+ corvette. The 05, at least mine, has the positive terminal closest to the fender.
I had the same problem as you on and off and I could not get the positive cable, IIRC, to stay tight. Fast Forward a few years, and I needed a new battery.
It seems the 05 battery has the +/- posts reversed from all the other c6's. Since the +/- battery posts are not the same size you will always have a bad connection to the car with the results matching your problem. So make sure that the battery is not for a 2006+ corvette. The 05, at least mine, has the positive terminal closest to the fender.
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it’s important to note that initially when coming back into my car , all I noticed was that I couldn’t put the window up. Everything else was fine for a minute. Then my electronics on the dash went black, and my gauges like gas level battery level etc all fluctuated to 0. I then got codes on the dash like “service this. Service this”. I then shut the car off and restarted it. It restarted FINE, except the the electrical issues were the same. The difference was THIS time the transmission was locked. I couldn’t move out of park. I shut it off again, and couldn’t restart it
could this have to do with the fuses or anything? It just seems weird that this happened out of nowhere a few weeks into a fresh battery that showed 100% capacity when they tested it
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sorry if I worded that wrong. What the battery tech told me was that when he tested the battery, it came back 100% capacity and charged. He said that for some reason even though the battery is charged, it’s not cranking any amps out. Hopefully that makes sense. He’s coming back soon to disconnect/reconnect the battery and I’m going to fill everyone in. Can’t thank you guys enough for the help and thoughtful responses.
Race Director
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I know it’s strange. But leaving the car running while taking the fob with me is the ONLY thing I can think of that I did differently. Otherwise I put the car in park and start it all the time.
it’s important to note that initially when coming back into my car , all I noticed was that I couldn’t put the window up. Everything else was fine for a minute. Then my electronics on the dash went black, and my gauges like gas level battery level etc all fluctuated to 0. I then got codes on the dash like “service this. Service this”. I then shut the car off and restarted it. It restarted FINE, except the the electrical issues were the same. The difference was THIS time the transmission was locked. I couldn’t move out of park. I shut it off again, and couldn’t restart it
could this have to do with the fuses or anything? It just seems weird that this happened out of nowhere a few weeks into a fresh battery that showed 100% capacity when they tested it
it’s important to note that initially when coming back into my car , all I noticed was that I couldn’t put the window up. Everything else was fine for a minute. Then my electronics on the dash went black, and my gauges like gas level battery level etc all fluctuated to 0. I then got codes on the dash like “service this. Service this”. I then shut the car off and restarted it. It restarted FINE, except the the electrical issues were the same. The difference was THIS time the transmission was locked. I couldn’t move out of park. I shut it off again, and couldn’t restart it
could this have to do with the fuses or anything? It just seems weird that this happened out of nowhere a few weeks into a fresh battery that showed 100% capacity when they tested it
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do you really think it could be a lemon? But why would it have worked flawlessly for 1 month then? It’s not like it immediately failed after installation. I’d hate to have to buy a new battery just to find out that it wasn’t the problem , especially after I already know the old battery was at 100% capacity
Race Director
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do you really think it could be a lemon? But why would it have worked flawlessly for 1 month then? It’s not like it immediately failed after installation. I’d hate to have to buy a new battery just to find out that it wasn’t the problem , especially after I already know the old battery was at 100% capacity
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Batteries are composed of a series of cells that store energy. A good example are the old batteries that you would have to fill with distilled water. Each of the caps was for an individual cell within the battery. These cells can go bad. If a cell goes bad, the battery can still show it has a full charge, but fail to be able to transfer that charge to the car when put under load (e.g. trying to start the car). This is why I suggested to have the battery load tested.