Voltage Problem-13 volts drops to 6 volts with engine running.

[rednekroketeer]

Completely stumped. I've been dabbling in car audio since my first car, and never seen this before. Started out by my amp (a crunch gp3000.1) just suddenly stopped producing sound. No pop or hiss or anything, just silence. Oddly enough the green power light still lights up, and I've went through everything, and notice a huge drop at the terminals from battery only voltage vs engine running voltage. I would get 13v on just battery, then the voltage would drop to 6v after starting engine. I have a DB Electrical 220 amp alternator and also upgraded the big 3. I thought well maybe ground problems(grasping at straws here) so I bought 20' of power cable and ran a direct ground straight to the negative battery terminal (just a test setup) and still get the drop. I have had this installation for almost a year with no problems until it just quit a couple days ago.... Any help is greatly appreciated. Oh yea, I drive a 88 Camaro, so no computers or any crap like that to drag the voltage down.

Click to read more...

 

[shizzzon 10+ year member]

If it drops that low.. Probably bad battery. Get it tested professionally to see how much capacitance is left in it.

 

[Papermaker85 5,000+ posts]

Completely stumped. I've been dabbling in car audio since my first car, and never seen this before. Started out by my amp (a crunch gp3000.1) just suddenly stopped producing sound. No pop or hiss or anything, just silence. Oddly enough the green power light still lights up, and I've went through everything, and notice a huge drop at the terminals from battery only voltage vs engine running voltage. I would get 13v on just battery, then the voltage would drop to 6v after starting engine. I have a DB Electrical 220 amp alternator and also upgraded the big 3. I thought well maybe ground problems(grasping at straws here) so I bought 20' of power cable and ran a direct ground straight to the negative battery terminal (just a test setup) and still get the drop. I have had this installation for almost a year with no problems until it just quit a couple days ago.... Any help is greatly appreciated. Oh yea, I drive a 88 Camaro, so no computers or any crap like that to drag the voltage down.

sounds like a bad power supply..