9v at Ballast Restor (pic)

[dust]

Is it normal to have only 10.6v going to the ballast resistor when the key is on? Battery at 12.1v.

When the line is connected to the ballast resistor, it drops to 9.1v and the other side 5.5v.

1970's Electronic ignition. Mix match of several parts on a 1972 Duster.

 

[RustyRatRod]

If that is the ignition switch side of the ballast, no that's not normal.

 

[67Dart273]

Did you check both sides of the resistor?

Probe both sides, and see which is highest. Then compare that to battery voltage. (It's possible the battery is that low if it's been sitting a long time, etc or poor battery)

If you are already on the "high" side, then you have voltage drop between there and the battery, and that is a LOT of drop

Your "usual suspects" are the bulkhead connnector (red wire from fuse link through connector)......the ammeter...........the ignition switch connector..........the switch itself..........back out the switch connector on "ignition run." ...........back out the bulkhead connector on the ignition run line.

 

[dust]

One side is 9.1v, other is 5.5v.

What's odd is that unconnected, it reads 11.1v at the connector. Battery is over 12v.

 

[67Dart273]

Of course it reads higher unconnected. You are experiencing "Ohm's Law." What you have is the battery, and harness (the source), the ballast resistor, and then the load........the ignition system. With no load there is no current, and therefore no (or little) voltage drop. With the ballast unhooked, you still have the load of the VR and alternator field. If you unplug the VR connector, it will probably go higher yet

If you don't have one, go over to MyMopar and download a service manual for free

Then read this article by MAD Electrical:

http://www.madelectrical.com/electricaltech/amp-gauges.shtml

 

[zombywoof]

the voltage on one side of my ballast resistor measures funny too. it all started after i installed my under dash a/c unit

 

[KitCarlson]

Don't be giving anyone ideas like that.

 

[zac_F71]

I have a similar issue, voltage regulator gone, Amp gauge bypassed, ignition side of ballast reads 6.0v's or so and 200* temp while running, you would think the electronic ignition and dist need 12v or so.. perhaps the resistor is not needed?

If I can't figure it out I'll probably switch to an MSD box or something similar.. and eliminate the factory stuff for now

 

[KitCarlson]

I restrained myself from insulting comments.