I posted this in the general area as well....

I just upgraded my stereo- new HU, sub, front speakers and 2 amps. All was fine after the sub, hu and 1 amp, but since i added the front speakers and 2nd amp, the battery keeps dying. I brought it in to the stereo place with a new battery installed and they said there isn't anything causing a draw. When I turn off the car, the amps shut off, the stereo is off, nothing seems to stay on, so I can't figure this out. The dealership put in the new battery and couldn't see anything wrong either.

I dont know what is up..

any ideas?


Steve

 

Maybe upgrade your battery to an Optima Red Top or even better a Yellow Top.

The battery may not be good enough, also upgrade the Big 3 (its in the C5 FAQ)

Or upgrade the alternator....


Your system may be drawing too much power and then not recharging fast enough to fill the capacity.

Just a guess.....

Good Luck,

Justin

 

i have a 450/4 jl audio with a 250/1. The battery is showing about 13.8 while I am driving.. is that not enough to charge it?

Steve

 

Maybe you just have a bad battery. Has the car sit without running and no charge on the battery for a long period? I had a GM that only lasted 2-1/2 years. My car sits a lot during the winter, and I didn't keep it chargeed.

 

I usually drive it 2-3 times per week. This time it sat for 2 days without driving. its toast now.

 

Optima Yellow got lots of juice.

 

didnt you install similar setup to me?

are you having any issues?

 

I added a sub and amp. Also I was doing a lot of interior install work. I killed by stock battery about 4 times, during that period.

Problem solved. Installed the big Optima Yellow top. So far, it's really nice.

Here is a thread to my Optima Yellow install.

http://forums.corvetteforum.com/show...=optima+yellow

 

no reason you should have an issue i did similar on a customers c5 stock gm battery still doing good and his car sits alot

 

I have a few ideas.... they might seem weird but it will help track down what is wrong.

The first thing I would do it double check your electrical connections. Check the alternator [+] and make sure it is securely held in place at the mounting bolts. Follow the main wire from the alternator to where it interconnects on it's way to the battery. Check the starter leads, too. Don't forget all of the grounds from the engine/frame/battery. Do the "Big 3" if you haven't already.

Check the battery + and - for a good connection, and make SURE that the terminals and battery are completely clean. If you have EVER had a battery leak or corrosion, then you need to neutralize the chemical reaction because any residual 'goo' (that's a technical term ) will conduct electricity and drain your battery.

If you have done all of that and are still having problems, then you need to have the battery tested. Batteries may be robust, but if you deep cycle them too many times (regardless of their age) they will die a quick death. By deep cycle, I mean drive them to a low 'volts per cell' level.

Deep Cycle batteries (Optima Yellow top, for example) are more forgiving in this instance, but you still need to be careful. If you have a perfectly new battery and haven't killed it, read on:

Look at the physical installation of your stereo to verify that you do not have a parasitic draw on your system. Pull the fuses for your amps. Turn off the stereo and remove the faceplate. See if the dead battery problem persists. If not, then you know it's one of your stereo components drawing current when the car is off.

Did you install the stereo system yourself, or have it done at a local shop?

Sometimes an installer will screw up and setup the HU to draw power in a vehicle-off state. (Confusing the batt+ and acc+ has been known to happen... and using batt+ for both in the case when they can't find a switched acc+ in a C5.) Sometimes they will use add-on relays, which end up staying powered up after the stereo is turned off.

If your battery stays 'up' with the stereo system shut down for a few days and you haven't found an obvious problem, then re-attach the face plate and see what changes. If it's cool after a few more days, then re-install the fuses of the amps. (one at a time, a few days in between.)

In the end, it could be that your electrical system just isn't up to the task of charging your battery and providing power to your car and stereo system. In this case, look towards a high-output alternator to help solve your problems.

Mark

p.s. 13.8 VDC should be a good indication of a proper charging circuit, provided you are not current limited.

 

I'll print that out bring it to the stereo shop. I didnt do the install myself and I am not technically inclined for things like that.

I dont know what the "big 3" is.

The stereo place installed a power cable from the positive of the battery to run the amps. What if I just pulled that off the battery? would that make a diff? The stereo place said that it wouldn't make a difference and they seem to know what they are talking about.

Steve

 

Steve,

Pulling the wire from your battery to your amps will remove the new wiring and amps from the equation... IF the losses are indeed within that pathway. It might be easier to pop the fuses, but do whichever you prefer.

"The Big 3" is the addition of three wires to your vehicle electrical system:

Engine to Frame
Frame to Battery Ground
Alternator to battery positive.

Most vehicles are designed/built with your vehicle electronics in mind, not a big stereo system. Sometimes the ground from the engine (which is where your alternator ground is) to the frame is not big enough to handle the demands of an amplifier. The same thing occurs with the wiring from your battery to the frame. This also is a problem with vehicles that have a metal body where the body is used as a ground conductor. (We don't have that 'problem' with a fiberglass/plastic car.)

Even if you are running a 4 AWG [+] wire from your battery to your amps, and a 4 AWG ground from your amps to your frame; if your ground from your battery and/or engine to the frame is a 8 or 10 AWG wire you are going to be limited as to how much current can flow to your vehicle devices AND your power amplifier.

Here is the thing: When current flows through a wire, the electrons are passing from point to point... but it's not a linear exchange. The wire has an internal resistance to current flow, and as your current demand increases you need to increase your wire size to be able to deliver the current demand without causing a voltage drop.

Quick physics lesson:

Electrons are moving from point to point within the copper structure of the wire. The copper isn't smooth at the atomic level, so the electrons have to find 'pathways' through the wire to their destination.

If you can imagine standing in front of a picket fence and hitting a golf ball thorough the opening in the fence, you can see what I mean. The golf ball is the electron. the opening in the fence is the pathway, and the fence is the resistance to the ball going to it's final destination. If you had a requirement for 10 golf *****/min through the fence, you need a bigger fence and more golfers to increase the numbers of ***** that can get to the other side.

So lets stop and think about what happens to the energy of the golf ball that does NOT get through the fence. It hits the fence and bounces back, right? The energy is transfered from the ball to the fence in the form of heat. (Not exactly 100%... but bear with me here.)

The same thing happens with the electrons. They cannot flow to the proper place, so they end up bouncing around within the copper and generating heat. This heat will increase the temperature within the wire, increasing the resistance of the wire. Basically boarding up the fence. Now even LESS golf ***** can get through!

Now imagine if we had to hit the ***** through multiple fences for a distance of say, 100 feet? The same thing happens in the length of wire. As the wire length increases, we need a wider fence (bigger wire) so that our golfers between the fences can hit the ***** through.

Thus endith the lesson.

So let's stop and think about the wiring in your car.. As your need for current flow increases, you need to increase the size of the wire to allow a higher flow of current without causing the wire to heat up and increase it's resistance.

By "up-sizing" your grounds (engine to frame, frame to battery) to a 4 AWG or larger (2 AWG, 0 AWG, etc...) you increase the electrical systems capacity to deliver current to your devices.

If you were to stop right there, I would call it "The Big 2."

The third wire is the [+] wire from your alternator to your battery. Every vehicle has this wire, but the path to the battery may be different from vehicle to vehicle. Normally this wire is sized such that the alternator can supply power to your vehicle for steady operation (engine, headlights, windshield wipers, etc...) as well as provide a charging current to your battery.

When you first start your car, you place a high current demand on the battery. (BIG cables from your battery to the starter & frame/engine.) After the vehicle starts, the battery will recover and accept a charge from the alternator. Your alternator will deliver as much current as is needed to run your car, and provide that charging current to the battery.

What determines the charge rate? The voltage supply (alternator) and the ability of the charging device (alternator) to supply current, and the wiring's ability to deliver said current. If the wire cannot supply the current, the heat builds up and the available voltage to charge the battery drops... which decreases the charging current. This basically slows down the rate at which the battery can recover from a decrease in energy back to a full rate of charge.

Here's the thing: The wire from the alternator to the battery is designed for a SHORT DURATION high-current demand that tapers off to a float charge current. What happens when you put a big load on the electrical system? You guessed it: the wire heats up and the voltage drops.

Add a big stereo that pulls a lot of current and guess what happens? Your available charge current to your battery drops and you start to shorten the life of your battery because it cannot recover from the discharge properly.

Make SURE that if you up-size the wire from the alternator to the battery that it is protected by a fuse on each end. BOTH your battery and your alternator are considered a point of energy, so fusing it protects the device, the wire, and ultimately YOU.

I hope I have explained this in such a way that it makes it easy to understand. Let me know if this helps.

Mark

 

It helps.

I may have to go back to college and take some physics and engineering classes. I think I'll print your post and bring it in to the stereo place for them to review.

I'll keep you posted.

This forum is great. Thanks for all the help!

Steve

 

A Red Top won't help him, it's a starting battery. He would need the Yellow Top which is a deep cycle battery.

I agree with the Big 3 but he shouldn't be having such problems with so little draw.

 

So I brought it back to the stereo place this afternoon after I got a jump. They said that the battery was bad. It was only 2 weeks old if that. But they said to go and buy a yellow top.

So. I did.

The yellow top is in.

We'll see what happens next.

Steve

 

Keep us informed on this when you can.

 

So...

after I put in the yellow top, the voltage was around 14.1 or so. I let it sit for 1 day (friday) and decided to see if it would start up today.

It did, but the voltage now varies from about 12.5 to 13.6.

I didnt do the big 3, as I am mechanically illiterate. I guess I could have the dealership do it. THat shouldnt mess with the warranty should it?

The car will sit again tomorrow, but it goes to the dealership on monday. I think I'll have them check the alternator as well while it is in.

Steve

 

This might be out of left field, but I've been having issues with my battery too, it's an Optima red-top. I went out looking for something behind the seats of my Z with a partition one night and to light up that area I opened the lighted visors to shine light back there. Well i forgot to close the visors, the lights stayed on all night and I had a dead battery the next morning. Got a jump and everything seemed fine but I've noticed now that I get random "electrical gremlins" from time to time. I also noticed one night when I went to get something out of the car that after unlocking, opening, closing and locking back that all the lights went out EXCEPT the lights around the guage cluster. It's done this several times and the only way to get them to go off is to hit the unlock button twice and then the lock button, weird. Not sure if they go out after a while(I waited 5 minutes and they never went out themselves without doing the double unlock then lock thing). By the way I still have the factory stereo in mine. Sorry to hijack your thread, just passing on what was killing my battery. Good luck.

 

You shouldnt have to do the big three in a C6. The system is up to par with the exception of possible DBS. I run a 450/4 and a 300/2 in my 06 (origional battery) and I play it very loud most of the time. Taking the stereo installers recommendation at this point is suspect. They have a motive to blame it on the battery. It might be but maybe not. There are alot of C6 cars here with powerful systems that havn't done the big three. I would guess its the battery or there is a draw somewhere.

 

I let it sit for one day, and it worked. I am now waiting two days without driving it to see if it will start on day 3, which will be this friday.

I did have it in the dealership the other day and had them check things and they said it checked out ok.

I'll get back with you all on friday. Wish me luck,

Steve