Ill take the battery in and have it tested tomorrow.

 

That is suspiciously low for a 95 model year car. It makes me think something has gone wrong executing the test procedure.
You should be somewhere around the 30 to 40 milliamp range after everything has timed out.
Even Hot Rod Roys 84 model year car is 13 milliamps and I know for sure he is measuring his properly. You are coming in at 10, which is lower than his car.
Im not trying to sound condescending in any way here, I just know the parasitic draw rabbit hole goes so deep, you will never get to the bottom of it unless the test procedure is done exactly right.

 

Maybe something weird about the scale on your meter ?
Take a picture of your meter if you want and post it …

 

 

That is 10 mA, but since that is the least significant digit it could be as high as 20 mA, still good.

 

Ya im sure its not the most accurate multi meter

 

You could try the 250 mA scale, but be careful as too much current will toast the internal resistor. It will give better resolution of the true amount of current if it matters.

 

Yeah I cant believe that doesn't say .03 or .04
But there it is …

I guess at least it doesn't say .1 lol …

 

I re ran the test both ways and they come out the same. maybe all that on of on off stuff triggered or loosened something? Im going to just leave it sit a few days all hooked up and see what happens. Thanks for the help i will replay back soon.

 

Go get your battery tested like you planned. Charge it first.
Interstate is by far and away the best battery, but every once in awhile even an Interstate will fail prematurely.

 

roger that will do.

 

One of the neat things about this Forum is that there are so many people willing to help! One of the unfortunate things about this Forum is that there are so many people trying to help! The problem any OP has, is to figure out the difference between those two statements! I haven't figured out how to stay out of trouble if I enter into the controversy. Here's a few observations:

1. That Craftsman multi meter is a very good meter, when used correctly.
2. You can't accurately measure 10 mA on the 10 A scale. That's the absolute bottom of the range on 10A.
3. The Harbor Freight "Fuse Circuit Tester" has the same limitation. It's just a multi meter with no selector ****. This tester has a minimum reading of 0.1A (100 mA) so it's useless for this application.
4. When you disconnect, and then re-connect anything during the testing, the interior lamp delay circuit will reset, and start the whole process over again!

 

Smart observations there Hot Rod Roy!

It is an awesome site where people can get answers for free and the advice from fellow Corvette Owners. It may not always be "good" advice but usually "IS" and remember you get what you paid for. I try to share my knowledge and am always willing to learn new things. If I am wrong I will admit it and I don't spend my time trying to undermine or criticize anybody else.

However certain people picking on one another gets a bit old very quickly, anywhere.

Hello again xFaKx, I am anxious to see what they found testing your Interstate battery. Unfortunately there is no easy way to measure the "Self-Discharge" rate of a battery. I use a "Load Bank" that I have that can give me a steady discharge so I can determine how many amp hours the battery can deliver. I use it for verification of a battery's capacity. You could remove all connections from your battery and let it sit for 7-10 days and get a rough idea about your battery's self discharge rate. To do so just measure the voltage every day and record it and after a week or 10 days you should be able to tell if there is an issue with the battery.

The way you tested the battery in #3 was correct. There are videos on YOUTUBE showing how to test for parasitic drains in cars. If you are going to have a car like this you might want to consider getting a higher end digital meter. I have two Fluke meters and I can't live without them as they are built to last and very accurate. The Fluke meters I have can give me three digits to the right of the decimal point for accuracy. The other electrical tool I use regularly on the Corvettes is a POWER PROBE 4 and it too is incredibly handy when you are trying to solve electrical issues. The Power Probe can apply battery voltage or ground at the tip simply by pushing a rocker switch, it is great when trying to find out if things really work.

I wish you the very best in getting this drain solved! You are well on your way it appears! By the way, I hope somebody said this earlier: Welcome To The Corvette Forum!
Best Regards,
Chris

 

Chris, I've searched hard for a good YouTube video on this subject, but NONE that I've found are correct for our Corvettes! Can you educate me, please?

PatternDayTrader's post #12 is the best description of the correct process, except that I also need an education on the "Draw Test Tool" that is referenced. Again, I come up blank on a tool that will work on the complex system in our Corvettes.

 

Hello again Hot Rod Roy,

I watched the YOUTUBE video made by "ErictheCarGuy" and the way he does it is correct for pretty much any 12 volt car.

First you set the meter up to allow it to measure amperage. This frequently requires moving a lead to another input on the meter. On a Corvette you would simply remove the ground wire from the battery and attach one of the leads from a meter to this wire (using some small clamp) and the attach the second wire to the battery ground post. My Meter has clamps that attach to the leads which makes it easier. The meter goes in between the battery negative post and the battery ground wire that attaches to the negative post.

It is possible to do this on the Positive side of the battery but that is a bad idea and a great way to start a fire.

To my knowledge there is no such device known as a "Draw Test Tool", I searched and only saw references to parasitic loss measurement which is what I have been explaining how to do to for the OP.

My favorite electrical tool besides my Fluke meters is the POWER PROBE 4. Look it up and read what it can do. The probe can even measure the kickback voltage from the injectors de-energizing. This is one handy tool for any kind of vehicle, I used mine on my Cessna all the time and finally my A&P Mechanic bought one after he saw what it was able to do. It is not cheap but a awesome tool it is.

In our lab we used current shunts which is the most accurate method of measuring the current. The shunt would go on the negative line between the battery and the car's electrical system. Here the meter is doing the same thing as the shunt only it has the amperage limitation of the meter. Am I describing this more clearly? I am not so sure there would be anything else different on a Corvette, my newest Corvette is a 1988 C4 and I know the test works on this car as I have done multiple times.

Does this help at all? I apologize that I can't be of more use on the newer Corvettes and their key-less entry systems. Let me know if this did not help you. I was taught the way I have explained it and never had a problem getting an accurate reading on the loss. I have been doing it with simply a Multi-meter for decades and never got any wrong answers.

I hope that this helps, even a little.

Chris

 

I believe he's actually referencing a J-38758 'Draw Test Switch' which is a Kent-Moore basic tool. Everyone does them OTC etc

Here's an eBay offering:

https://www.ebay.com/itm/Kent-Moore-...-/392134346692

If you do a SEARCH of the entire CF from the SEARCH 'drop-down' for just 38758 you'll find some 'maybe' interesting reads. I believe there's a half dozen or so. I read quickly one that seemed fairly through.

It's also in many of the later C4 FSM - 6D1 section. '90 and later for sure.

Connected from a later C4 FSM

 

Yes … Kent Moore supplies the tool.
Its pretty darn handy too.
The jumper wire is the best way to improvise, and frankly, its not nearly as good as the tool.

 

That's why I use a Fluke I can view any range I like

 

Don't take it personally. Really.
The issue with measuring parasitic draw, is that there is no room for error, which is why two competing ideas about the test procedure, just isn't going to work out.
Now you have the true facts. For myself, I hate being wrong, so next time you see that happen, make sure you point it out forcefully, that way ill believe you, because staying wrong is a thousand times worse.

 

My old fluke87 wont shut off anymore. I turn the dial to off and nothing happens. I guess two decades of service has taken its toll.