What is the cause if the engine stops running when the negative battery cable is removed from the battery?

I also have voltage from the removed negative battery cable and the negative post when the ignition is off. I know this refers to a short somewhere.

 

Generally, when the battery cable is removed, the alt. is supposed to keep the truck running so I would say bad alt. Any auto parts house can test it for free. As far as the voltage goes, you should have a little for the clock, radio, etc. The parts house can check this at the same time. Hope this helps

 

yeah I was fooled b that also-you will see a negative drain when truck is off-as animalistic said for the clock e.t.c-if you pull the battery cable and she dies you got a alternator problem-9 out of 10 times!!!

 

If you want to ck for draw just take a test light and put it inbetween the neg cable and the neg post. If the light is bright you have a draw, if its dim its normal. But a parts store will be able to tell you if its the alt or an electrical problem. I had a bad ground and the alt wasnt charging enough, so after running for like 20 min when you turned it off it wouldnt turn on, if it did it was real slow.

 

Thanks for your advise. Again, I love this sight! I have always gotten great and valuable advise from you guys!

 

Yup, the alternator did the trick. I still have 12 v between the neg cable and the battery. But I haven't driven it in a couple days and went out and it statrted right up with 12 v on the gauge. Please let me know if there is another problem maybe.

Thanks again.

 

Glad to hear the new alt got you running again. Some voltage is normal but the best way to test the draw is with an amp meter. You should have 12 volts but such a small amount of amps that your meter barely shows it. As a general rule, anything over 2-3 amps means you have a short somewhere. Start pulling fuses until the amps drop. Don't forget about your dome light! That one cought me once.