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Back to basics regarding testing for shorts

cmayna

cmayna

DILLIGARA?
Donator
Messr. Midlife,
I think the boss (4 wheel type) might have a short somewhere because recently I have left the new battery connected and
the last two times I have let it sit for 2-3 days and then fire it up, initially it barely turns over and then it suddenly
fires up.

Is there a good writeup for us back to basics kind of people on where to start. All stock gauges with only a
red idiot Alt light.


Regards

Ivanna Cheque Forshorts
 
IMO
Keys out of the ignition.
Start with an AMPmeter and hook it up at the battery.
Look how much current is drawing from the battery.
Pull fuse by fuse till the current is almost zero.( just a current piek from the clock maybe )
If there is still some current flowing , you have big problems :stu
 
If you have big problems I would :
Disconnect the voltage regulator
Disconnect the alternator
Disconnect the cluster
ect ect
Till the current drops to zero.
Just my 0.02 opinion. Dude. :stu
 
Simplely remove neg cable from batt and install a test light inline. Cable-test light-batt post
Now start by removing fuses one at a time, did light go out? Yes... what fuse cause it to drop draw, this is were to look.
No?... after all the fuses are out move on to removing voltage reg harness, headlight switch, ect till lamp is out.
Once you know what is drawing the voltage, you can isolate why.

Ps. Don't forget to remove the alt's charge ring from the starter sol too.
 
"Mach1Rider" said:
Simplely remove neg cable from batt and install a test light inline. Cable-test light-batt post
Now start by removing fuses one at a time, did light go out? Yes... what fuse cause it to drop draw, this is were to look.
No?... after all the fuses are out move on to removing voltage reg harness, headlight switch, ect till lamp is out.
Once you know what is drawing the voltage, you can isolate why.

Ps. Don't forget to remove the alt's charge ring from the starter sol too.
Click to expand...
This is close enough, but I prefer to put a DVM in place of the test light. By measuring the actual current draw, you can get another clue as to what may be happening. Typically, 1-3 amps is a bulb; 0.100+ amps is a gauge or radio that draws continuous current; 10+ amps is a dead short.

I always do this check whenever I have disconnected the battery and just prior to reconnecting it back up. The last thing I want to happen is just after battery hook-up, you turn your back and you smell something suspicious like burning insulation.
 
Hopefully I set up the DVM correctly. I disconnected the positive cable from the battery and hooked the meter between the cable and battery post getting the following reading. I disconnected the voltage regulator and then the alternator wiith no change. I guess it's time to start pulling fuses. Oh joy !!


4-240511055208.jpeg
 
Last edited by a moderator:
No, that is not the correct set-up. You need to put the red lead into the upper left hand plug, which is used for DC and AC current. If your reading is less than 0.6 amps, then you can use the lower plug.
 
Well after hooking it up as suggested I'm getting a reading of 0.00 which I can't believe. This is again disconnecting the negative wire from the battery and installing the meter between the negative wire and post.

What the heck am I doing wrong?
 
That's good...that means you're draw is less than 100 milliamps or your fuse is blown. Check the fuse, then if it is OK, go to the 300 mA plug.
 
The fuses are inside the DVM. 2 pc
The 10 amp fuse is a special one I believe.
Check your Fluke manual for spare parts.
 
With Midlife on the phone to me, I checked both fuses and they tested just fine. Odds are the car is just fine and maybe it is a crappy battery. Nevertheless, I'll keep the battery connected for a few days and then reattempt to turn the motor over. Maybe it was just me dreaming that I had a problem with the car's electrical.
 
"AzPete" said:
And I guess you would know what you checked into.....
Click to expand...

And wouldn't you know it, we didn't find a damn thing! *LOL*
 
"cmayna" said:
With Midlife on the phone to me, I checked both fuses and they tested just fine. Odds are the car is just fine and maybe it is a crappy battery. Nevertheless, I'll keep the battery connected for a few days and then reattempt to turn the motor over. Maybe it was just me dreaming that I had a problem with the car's electrical.
Click to expand...

The battery is no doubt junk. They don't like to sit dead for very long. If I recall correctly, it sat for 3 years without being started. Yeah?
 
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