Challenger electrical problem

[06Daytona]

A few weeks back I ran the Challenger out to see the Cuda progress. It ran fine on the way out there, but when I went to leave the car died. We checked the alternator with a voltmeter and it was working fine, but my aftermarket volt meter in the car was only reading about 10 or 11 volts. It starts and runs fine from jumper cables, but once the cables come off the car dies. We changed out the regulator with one that was known to be working and it didn't help. I checked the black wire from the alternator where it plugs into the firewall connector and it had the same voltage as it did at the alternator, so I know the wire is fine.

Could this be the ballast resistor? It's been a while since I've chased electrical gremlins, so I can't remember what pieces do what.

We ended up running a wire from the alternator directly to the starter relay and it kept the battery up so I could get the car home, but the voltmeter was reading from high 13s to 18s. I'm a little worried that the battery is going to blow on me since I've been driving the car this way the odd time.

[Chryco Psycho]

Battery voltage should be 13.2 running it should be 14-14.5v
not a ballast resister for sure , sounds like 1 of 3 things , ungrounded reg , bad alt or bad wiring , you should have 12v to the blue field wire & the blue wire at the reg , the green wire from the alt field connects to the green wire on the reg & the reg has to be grounded 

[Chryco Psycho]

How is the Cuda coming along ?

[06Daytona]

I'll check all those today. The Cuda is coming along. Renee spent some time patching bits and pieces while he was waiting for trunk supports. The back end of the car is pretty much back together now. I'll be getting some pics next week.

[dodj]

We ended up running a wire from the alternator directly to the starter relay and it kept the battery up so I could get the car home, but the voltmeter was reading from high 13s to 18s. I'm a little worried that the battery is going to blow on me since I've been driving the car this way the odd time.

With that wire from alt to battery, the VR should still be functioning and keeping you around 14 vdc.  Check the grounding of your VR, field wiring along the valve cover. Swap out the VR if no faults found.