Why is my battery sparking?

[DeNoZZo]

When I attempt to hook up my battery it starts sparking. I can get them all on with no sparks at all when the alternator fuse is out. But when I have the alternator fuse in, and I hook up the positive side first, I can't get the negative on without major sparking. Any ideas on whats causing it to short out?

 

[GSXeclipsePSI]

I always hook up my NEG cable 1st and I still have small sparks, you pulling some volts from the battery even when car is off. I believe the radio/ecus memory function alone is enough for sparks.

 

[DeNoZZo]

I always hook up my NEG cable 1st and I still have small sparks, you pulling some volts from the battery even when car is off. I believe the radio/ecus memory function alone is enough for sparks.

It was sparking pretty hardcore. I think it's shorted out somewhere.

 

[#40Fan]

Negative cable should always be last. That way if you accidently touch the frame while tightening the cable, nothing happens. Try touching the frame with a wrench while it is also connected to the positive side and see why you should always do the negative last.

 

[GooeyGus]

Connect the neg cable and then test for resistance between the neg and the positive clamp that goes on the battery. If it is shorted you will have very low resistance.

 

[DeNoZZo]

I took the alternator out and connected the part of it that contacts the block straight to the ground and it still shot sparks. So I think It's shorting out somewhere. I plan on taking it into the parts store and have them check it tomorrow

 

[luv2rallye]

Do you have a large capacitor on a high power amp which is on the alternator circuit? Capacitors are a direct short until they chargeup (which is exponentially). This is why resistance measurements across the battery cables (w/o battery connected) are often misleading and the reading changes with time.

 

[ballersixty9]

you might have a ground somewhere

 

[DeNoZZo]

Do you have a large capacitor on a high power amp which is on the alternator circuit? Capacitors are a direct short until they chargeup (which is exponentially). This is why resistance measurements across the battery cables (w/o battery connected) are often misleading and the reading changes with time.

Nope, no amps for me.

new alternator solved my problem