Well, here I am again, same old problem. 1+ years ago I was dealing with drained batteries for my 86, lasting only 3-4 days, after purchasing the 3rd one in less than a year, I had it towed into the dealership to find the problem . . . they said it was the power switch to the seat, located under the center arm rest, and by removing the relay fuse each time I park it I would avoid this battery problem. I still had to start it once a week or it was dead though. I did this for a year until this week after one week of not starting the car the batterey was dead, won't even click. Before buying yet another new batterey or taking it in and spending another $600+ to have them tell me what they think is wrong, any idea??? I heard second hand that if you don't drive the car a good amount of time often then the battery will loose it's charge, that just starting it and letting it run is not sufficient enough. Is this true?

I'm so bewildered and tired of this, has anyone else gone through this?
Thanks, Paula

 

Your battery should last a lot longer than a week.
If you don't want to spend any more money searching
for the problem, buy a Battery Tender and hook it up to your
battery when you know you won't be driving it for a few days.

Jim

 

Thanks, Jim, I will look into this, could be a good temporary solution.

 

Been there.
Best option when not in regular use is to install a battery cutout switch and use a tender as mentioned. Having to reset the clock is alot easier than push starting.
Utimately you need someone to check the battery current draw too see if car is drawing more than it should.There are several other items that commonly fault and draw curent,
Headlight motors for one.Fan control module on climate control A/c is another.

 

I agree with the post above. A battery should last longer than a week and to use a Battery Tender. An '81 I owned had a power drain from the analog clock.

 

Check your under hood lamps.. they are a problem that I have from time to time.. look under the car at night once in a while, if you see light, that is your problem.. disconnect the connector or buy one of them switch kits.

Have you monitored your Voltage which driving.. is it in the 13.5+ range while running and what does it drop to if you turn on the lights and AC. If it drops your charging system is bad. Have it checked.

 

I will do that, thanks. I have looked while driving and it is 13+ with lights on, haven't checked with the a/c turned on. Just got it running tonight, bought a charger, battery was too dead to take a charge, so my son took it out and took it to Kragen and had it charged and tested, they said it charged ok and is good. Put it back in the car tonight and it started right up. But in the process he noticed two wires, one frayed, one cut - we don't know what they go to, I will try to attach pics for help from everyone/anyone. Also there is a loose/cracked connection/piece/plastic cap, also took pics. Obviously I know very little, and have spent too much, only to find out the dealership was not right about the battery problem or my a/c, so I am reluctant to return there. They said it was the power seat switch draining it, so I pull the relay/fuse each time it's not in use, sort of a pain, as it also goes to the windows, don't care about the seat moving, but windows - yes, so I have to put it in each time I drive it, but it still drains if not started at least every 5 days. Anyhow, thank you for the advice, I will follow up on that.

Ok, I tried to attach pics here, woe is me, sorry about the pic sizes. But can anyone tell me what these are, the cut wire and the cracked cap and could they contribute to the battery drain, and would a service garage like a Chevy dealer not notice these?

Paula

 

The first two pics are of the EGR vacuum solenoid. Should be fixed. The latter two are of the engine coolant temp sensor. It turns on the cooling fan as soon as coolant temp hits 227.

May or may not be related to your drain issue, but definitely get them fixed.

I had a battery drain issue a while back. I found it when I can hear my seat motor after I shut the car off. The power seat switch was stuck in the up position, and was trying to 'move' my seat up. All I did was wiggle the switch up and down to maybe loosen up the gunk. Don't have any more battery drains after that. If you are certain it's the switch, just get another one from here and replace it. Good luck.

http://www.tld-corvette.com/Aboutus.asp

 

Thanks! All very helpful advice. How strange that these things were never noticed before after 3 trips into the dealership garage, once for transmission work, second for the a/c, and third for the battery drain.

I will definitely get them fixed.
Paula

 

I hd the same problem with my 86 L98....the drain turned out to be the underhood lights. I just disconnected the wires from the harness which is located next to the headlights, and then just hook them up when needed. I keep them unhooked. This took care of my battery drain problem.

 

I agree with all of those posts, it can be many things and definately get the wires repaired... one thing that gets overlooked often is the grounding, there should be clean, tight connections at the battery terminals (the engine should also have it's own ground cable near the rear of the engine connecting the engine to the frame) and the positive cable on the starter, and the connections on your alternator. All should be clean and tight.
Running the car for a brief time every week or so is good for the mechanicals, bearings, seals, etc... getting a fresh coating of oil and some movement; for the battery, it takes a while... a good hour long "sunday drive"... to keep it fully charged. If you don't drive it often, it will die. Even the memory on the radio uses some of the voltage, the security system, any one of the wires that remains hot with the key in the off position could be the culprit...

Batteries need that good ground, it increases the potential... the difference between the positive and negative in the same source, in this case your battery.

Another thing that you can do on your own, over time, is pull fuses, and keep track of how long your battery stays charged. Pull you accessory fuse, recharge the battery check it after a few days or week, and if it is dead replace that fuse and try another.... I know it sounds like a pain in the butt, but it is free, and if you don't drive it that often you should be fine, wanna drive it, charger it replace the fuses and go!

Once you have found which circuit is the problem then dig deeper, or take it to a shop and give them that knowledge so they know where to start looking, instead of wasting your money looking where you already know it is good.

Good Luck and have fun learning about your own vette!

GH

 

The sensor in the pic runs the analog guage. The ECM turns on the primary fan using the info from the sensor in the front of the intake manifold.

 

Thanks! Great advice, everyone has been such a big help. My son soldered the wire that was cut as a temporary solution, I'm so thankful for his help - this is all new to him too, and I ordered replacements for both parts today from Ecklers.
1 30545 Corvette Knock Sensor Or Part# 305 $9.99 $9.99
Cooling Fan Switch Conn 45
ector, 1981-1995
1 53262 Corvette Solenoid Connec Part# 532 $10.99 $10.99
tor, EGR, 1985-1996 62

I hope I find the drain myself by doing the trial and error method.

Thanks again to all for the advice!!!!!!!!! I really appreciate the help!
Paula

 

Before my car's battery drain was repaired, the battery would last about a week. It turned out to be the stock alarm system. I'm sure your car has the same as mine so that may be something to look into.

As mentioned, put a tender on your car and your dead battery woes will disappear. The problem will still be there but the result will be gone. Even though a tender will fix the battery drain problem, you should try to fix what's causing the drain.

 

When we got our 90 last summer, the battery would sometimes completly drain in less than 12 hours. By luck, by chance, we found the emergency bake and rear hatch was used before a battery drain. They are both on same circuit. I found that emergency bake switch was not working right and the hatch switch on center console was not working at all. I was able to adjust both and no problems since.

Rick & Carol

1990 Red Coupe

 

My car has a stock alarm system?

 

Come to think of it, I did have the rear hatch replaced a few years back, and never had this problem before then. Hmmmmm, thanks will check both these out. Thanks!

 

Do you have or can borrow a multimeter?

What you want to do is check the drain on the battery. To do that, turn off all accessories, unplug hood lights, close doors and take the key out. Now, disconnect the positive terminal, set the multimeter to ammeter setting. Take one probe from the multimeter and touch it to the battery and touch the other probe to the disconnected battery cable.

If this is a high reading whatever is shorting out should be fixed, you don't want your car catching fire.

If its a low reading I would do the two things suggested:
Buy this
and this . Now plug in the battery tender when you park it, and unscrew the battery switch when its going to sit for a bit.

Do you still have the stock Bose stereo? Does it make funny buzzing noises or anything? sometimes the relay (behind dash) can stick and keep power on after key is out.

Good luck.

 

No, I don't have one or heard of one, but can certainly get one. We will do this, thanks.

Yes, the original Bose stereo is in it, no buzzing, but definitely static when the bass sliding bar is moved.

Thank you, I will get this checked out also.

 

You have high leakage current discharging your battery. GM says leakage current (battery current drawn with everything off) should not exceed 50 milliamps. My 87 draws 27 ma. and I have no battery problems. First, don't leave your key in the ignition as this keeps the theft alarm circuit on. Next, at night, in the dark, see if your underhood lights are on, vanity mirror lights, center console lights, door map lights, spare tire lights, courtesy lights. Do you have a radar detector, GPS, CB transceiver, aftermarket radio or audio amplifier? Check em.
Next, buy a VOM test meter (voltmeter, ohmeter, milliameter). You can buy one at Harbor Freight for $7 and its a pretty decent meter too!
Pull your courtesy light fuse, then disconnect the negative battery terminal and connect the VOM set up to measure current and connect the test probes from the battery post to the battery cable so you can measure current. It should be less than 50 milliamps. My bet it is much higher, then start removing fuses one at a time and watch the ammeter. If you see a dramatic drop, then that fuse circuit will need to be investigated. Seat motor switches sometimes are the culprit, keeping a seat adjust motor on. Feel seat motors, if warm, then this could be the problem. Also, remove the nut on the bolt behind the battery with 8 red wires connected. Remove the wires one at a time while watching the ammeter. Again, a sudden drop in current indicates the problem and you will have to follow that red wire to see what circuit it is.
Lead acid batteries don't like sitting for long periods (4+ wks). They self discharge even disconnected and while dead, the battery plates become sulfated and they will not take a charge and you have a door stop! If you park your car for a long time and you don't have high leakage current, then buy a battery tender and connect it to the battery. Tenders continually measure the battery voltage and charge the battery if its state of charge falls 10% and then shut off. This keeps your battery up and it will experience a normal life. Battery tenders may not be able to supply high leakage current and some tenders will indicate that you have excess leakage current.
Putting a battery disconnect switch on your battery doesn't solve the root of your problem, it hides it, and also, you will lose your radio station presets and miles driven info. Forget the battery switch and find the problem.
I'm surprised the dealer who told you the seat switch was stuck didn't replace the switch!