Need Help!

[rbsWELDER]

Several times this summer, a dead battery has limited me from maximizing my fun.

Background:
-I had the alternator checked at AutoZone and it checks OK.
-I had the battery checked at AutoZone and it checked OK.
- I checked the electrical circuit with an Ohm Meter, and it shows an open circuit, so there is no draw on the battery when the car is turned off.

Any ideas?

Thanks in advance

[Bill Cleveland]

Most of the guys in St Louis use one of these battery shut-off switches, including yours truly. For some reason, even though there is no visible draw on my system, the current leaks out somewhere. The cutoff switch solves the problem! (Plus, it's a security feature!)

batt switch.jpg (16.23 KiB) Viewed 683 times

[winfield scott]

Mark did you check with a voltmeter to see if there is any draw?

[Orville Duncan]

One of the best ways to check for parasitic draw on your battery is to disconnect the neg wire. Connect a test light to the neg. post and then the neg. wire. Make sure everything is turned off. If the light is lit even dimly, there is a draw on the battery.
The draw could be a radio memory or the car computer if it has one, Bad insulation on a wire or bare spot. I did see once see a relay wired wrong, that had to be energized in order to turn the horn off. Simple rewire of relay fixed that problem. Good Luck.

[rbsWELDER]

Windy - I disconnected one wire from the battery and checked the Ohms between the red and black wires. It showed an open circuit.

If I did that wrong, please give me a step by step procedure.

Thanks & Stay Warm!

[winfield scott]

Mark, disconnect the Neg.cable then set your multimeter to Amps put one lead on the battery post the other lead on the Neg. cable.
That should tell you If you have any parasitic drain.

[rbsWELDER]

Thanks!

[Indycars]

X2 on Winfield's suggestion, that's the way I would do it.

First setup the meter to measure current[10A], similar to the photo below. If you measure near zero amps, then move the RED cable to the "mA" port for a more sensitive measurement. Your meter maybe different, so pay attention and don't damage the meter.

http://www.engineersgarage.com/tutorial ... nt-testing

[attachment=0]MultimeterProbesSetForCurrent.JPG[/attachment]

The photo below shows how you would connect the meter above to measure current that would drain the battery. If in doubt how to setup and measure, then ask questions before something goes wrong and causes financial distress..... hehehehe!!!.

[attachment=1]ParasiticBatteryDrain.jpg[/attachment]

[rbsWELDER]

Rick & Windy,

Well I am back at it, after a brief break, for surgery, to fix a hernia; and a few days in St. Louis to visit the kids for Turkey Day!

I tested the draw on the battery per Rick's great directions. It showed a draw of .01 amps on the first try. After going inside to warm up, the second test showed "-0.00", and this reading repeated several more times. When it read this, I flipped to a finer scale and the meter read 0.00.

Any additional thoughts?

If I get a half warm day, I need to top off the gas for the winter hibernation, I will swing by Auto Zone to test the battery and compressor again.

[rbsWELDER]

Most of the guys in St Louis use one of these battery shut-off switches, including yours truly. For some reason, even though there is no visible draw on my system, the current leaks out somewhere. The cutoff switch solves the problem! (Plus, it's a security feature!)

batt switch.jpg

Bill,

Do you put these switches on the plus side or the negative side of the battery?

Thanks