I have been having the Charge System Fault code for a while now so I pulled the battery out and took it ot Oriellys to have it tested. It was showing 12.2 V and said it needs to be charged and showing only 45% Charged and that the battery tests good. So I left it there over night to have it charged up and tested 24 hours later. The tester still shows 12.2 V charged to 51% and the test shows good. My question is, is this battery really good since it sat on a charger for 24 hours and it only charged 6%? Its an optima if that helps any.

 

You know the answer to this...battery needs to be replaced if it won't fully charge and stay that way with no load. Might work for a while in your truck or Toyota but will only cause annoying problems in your Vette.

 

We were able to get the charge up to 12.86V and it load tested good and tester said it was 100% charged. Brought it home and I still get the Charge System fault and P1637 code so its on to more troubleshooting.

 

Is there another type that won't leak acid? That is the main reason I use them in my vehicles ( by the way I have had great luck with them too) I am open to suggestions since the one in my coupe is 5 + yrs. old and the ones in my camper and ****** are even older.

 

battery tender will not charge battery only maintain it best way to charge 2 amp slow charge 24 hours or more every 4 -6 hours ljft battery couple inches and drop being careful of acid splash this will dislodge any lead sulfate that built up on plates and allow battery to reach full charge thereafter use a battery tender and you will avoid these problems ps fully charged battery fresh off c 24 hr charge should read 13.5 volts

 

You are getting a charging fault and you just checked the battery?
Did you check the alternator voltage with the car running to see what voltage it is putting out?

 

Well, I am convinced it has to be my battery. I had it tested today and it tested good and was fully charged. I put it back in the car and got the code on first start. I then hooked my float charger to the battery and put on 2 amp charge. I then started the car with no code. I shut it off and restarted it 5 times and never got the code. I hthen pulled the charger off and I got the code on the very next start. So with the charger on the battery I get no code and with the charger off I get the code. Any ideas?

 

My alternator is putting out 14.4 v

 

Yep, I think I may have just fixed my Charge System Fault P1637 code. My fingers are crossed! I replaced the Optima Red Top with the Sears Die Hard Gold and I have yet to have the code thrown. I ran a few errands around town this afternoon and never got the code where as I would get it every start. Also, I noticed I now see a pretty steady 14.1 Volts on my DIC where I use to only see 13.5 to 13.6. Hopefully this was the fix for me. I was really hoping I didnt have to pull the right side Long tube off to get to the started. So like I said FINGERS CROSSED!

 

In the future, stay AWAY from the OPTIMA RED TOP.. It is NOT enough battery for your car! If you MUST have an Optima, buy a Yellow Top w/120 reserve. Otherwise, make sure your AAA is paid up to date.. You WILL be WALKING sooner, and later! 8vette7 knows his stuff! 13+ vlots from the battery tender is what's needed to keep that battery in check. If you are at 12.2, the battery is DONE! Glad to see you switched to the SEARS and didn't drink the Optima KoolAid again. Im not a fan of Optima anymore.. Their quality has gone away. Another option is the WalMart battery. 1/3 the price of Optima and you don't have to deal with the bad customer support if you have a Optima failure. Optima may as well not have a warranty because they DON'T stand behind their product!

OK. My flame suit is on because Optima is a forum supporter, but they treated me like CRAP! I had a 2 month old Red Top and it was defective from day one! When I tried to get warranty satisfaction from another Optima dealer in another state, the guy that did the so called warranty claim and upgraded me to a Yellow Top (for another $50) called me a few days later saying that Optima said my Red Top wasn't defective "enough" and they wanted their Yellow Top BACK! LOLOL Needless to say, they claimed 12.2v was enough for the Red Top to be within specs. Maybe for a 1974 Honda Civic but NOT for a 98 C5 Vette. Yellow Top is still in my car and when it dies in another few months as I would expect, Im going to put in a ACDelco and be done with the problem. There are as many GM dealerships around the country that I doubt ill ever have another warranty issue again!

 

I'm a big fan of Battery Tenders, however your battery readings indicate that they were in fairly good condition. A batttery that hasn't been cared for and has slipped will need a more aggressive charger to save it if it can be saved. Should you be able to "jolt" it back into the game with a more aggressive charger, its then when the battery tender may be able to keep it above water.

 

Well back last feb. I was doing some work on the car anddidnt put it on the charger and the batery got so low that my FOB wouldnt even unlock the doors. That is the main reason I was suspecting my battery.

 

8vette7 knows his stuff!.. He spent a lot of time and several posts back and forth with me to fix MY issues. Chuck is a great guy and I would trust his word over my local dealer any day of the week!

 

I really am new to sports cars, my younger years were spent on motorcycles and when performance bikes went to cpu controlled fuel injection I found nursing a marginal battery in these bikes actually slowed them down. I have to assume a hot or correctly functioning electrical system (ie. good battery and charging system) will allow the engine to not be held back by a marginal life support. My C5 gets battery tendered on a fresh battery always. And when I'm old enough to need a pacemaker I'm gonna change the battery more often than recommended

 

Have you had the charging system load tested yet? You can take it to Autozone or similar and they can do a charging system test for you. Maybe there is an issue with the altenator regulator. I don't know off hand if the regulator is in the alt or if regulation is performed by the pcm.

 

Leaking batteries were an issue back in 2000. Since then, non-AGM battery cases have been very robust and essentially, bulletproof. In other words, you should not worry about leaking batteries.

Your Diehard will do just fine. I use an AC Delco Professional 7YR battery but even a Costco Kirkland or Walmart MAXX battery will work great in a C5.

 

I wasn't refering to the leak around the side posts, I mean the leaking acid / fumes from the removeable top caps. I always liked the Delco batterys for quality and long life but want a battery that won't get acid on anything.

 

I believe something like that would happen only if the alternator's voltage regulator let loose and overcharged the battery. While that was not uncommon back in the day when the voltage regulator was not an integral part of the alternator, it is very rare nowadays.

C3s have their battery right behind the driver (inside the car, not under the hood), so a sealed battery was a safety necessity. Back in the day, batteries has a tube that would carry acid/fumes out from the inside of the car in the event of an overcharge condition. Today, we really don't have to worry about stuff like that.

 

...just someting to keep in mind whjen dealing with an automotive battery.
No matter who built the battery OPEN CIRCUIT VOLTAGE on a fully charged battery is 12.6volts period. If your battery measures higher you need to remove the "surface charge" which can be done by simply turning on the headlights for 1 minute or so. After doing this you should then measure the open circuit voltage. Anything below will require you to charge the battery then remeasure OCV. If your battery is not capable of registering 12.6V it's time for a new battery. Refer to the below for relative battery state of charge.
Open Circuit Voltage (12 V) Open Circuit Voltage
12.65 V 6.32 V 100%
12.45 V 6.22 V 75%
12.24 V 6.12 V 50%
12.06 V 6.03 V 25%
11.89 V 6.00 V 0%

Open circuit voltage is also affected by temperature, and the specific gravity of the electrolyte at full charge.

 

If you suspect any problems with your batter, then replace it.It's cheaper than having it go bad on the road or a trip. My 04 was having a lot of weird problems, loosing key info,miles remaining on gas in tank and others. I put a new battery $68 in it and have had no problems since.
cmanhome in Jax., Fl.