I would like to measure any parasitic battery drain that my exist in my elec system. Having two batteries I don't know which cables to disconnect and don't know exactly where to attach the clips. Also I need to know what value to set the selector to.

Thank you


98 1/2, 3500, 4x4, 5 spd

 

Disconnect the positive battery cable on the drivers side. Set your meter to read amps and touch one probe to the battery post and the other to the disconnected cable.

All power needs to run through the meter to read current draw. Don't try to start it or don't turn the key on and cycle the grid heaters. You meter won't like measuring that kind of current.

 

Like he said your meter wont like that kind of current, if you have a fluke like mine, it will blow the fuse because they are rated for only like 10 amps, any more and the fuse is toast and they are like $15 a piece

 

al so turn everything off and dont forget the light under the hood ,glove box ,trailer brake ect !

 

I put the voltmeter selector to 2 and got a reading of .015. Wow that was easy. Thanks for making it easy to understand.

Just for giggles I opened the hood until the light came on and took another reading. Gave me a reading that kept climbing, why is that?

Thanks guys.

 

http://www.theautoist.com/multimeter.htm

Here's a link that might help. It explains using diffrent scales on your meter. Might be handy to other folks too!

 

Make sure you put the meter on the 10 amp setting first or it will blow the small fuse. They are not cheap either.

Also make sure everything is off including the heater blower and stero and anyother hang on's.

You typically will get 250ma draw on first contact. I'm told this is the alternator being "excited". then you will get very small draw if any. It's usually only the very first contact and you will see a small spark then nothing.

I've just completed 2 different streetrod wiring systems and this is exactly what I saw. Normal they tell me.

 

Thta's a great link to the multimeter, Charliez! Thanks, Kurt

 

You will have to unhook both batteries to get an accurate reading. They are connected in parallel.