massive voltage drop with key on

[sandman 315]

so everytime i turn my key on i can watch my voltage drop at roughly .01 volts per second consistanly, ive unplugged everything on the harness in search of what was causing the problem, i can pull the main fuse and the voltage will jump up 3 volts instantily, and then climb back up at roughtly the same rate as deceleration. with the main fuse in if i pull the red wire going to the starter selonioid everything will climb back up.any ideas? anyone ran into this problem?

 

[pamcopete]

sandman,

The battery voltage will decrease under load, that is normal. How low does it get to after, say, 20 seconds?

If it drops too low, then you could have a bad battery that does not hold its charge under load. The voltage will climb back up even to 12 volts, but that is what is known as "surface charge", meaning that just the ions closest to the surface of the plates have a charge on them, but there is no depth of charge, so the surface charge quickly dissipates under load.

If the battery was good, then it would take more than 20 Amps to draw the voltage down that quickly and that would blow the fuse or fry a wire.

Take the battery down to some place that can do a load test on it, like Autozone or Advance Auto Parts.

 

[pamcopete]

See above

 

[frwinks]

hi sandman.. my first post on the forum and I'm hoping you/we can solve our issue
I'm seeing a massive draw on my 400 when I plug in the regulator

Pete, do you know if the chrysler/radio shack RR would work on a 400? You seem to have these systems perfected.