01 Cummins alternator 1-wire conversion questions

[Rogan]

Hey, guys.  I've already converted my 12V truck to the 1-wire setup (technically, it's 2 wires, but w/e..)

Started on the '01 today and realized quickly that the alternators are not the same  LOL

 

The internal regulator mod is pretty straight-forward, at least, on the dual-tab style alternators.  But the plug-in connectors, the internals look way different.   I've searched and searched to try and figure out where the field wire connectors inside the later style are, but to no avail.  I only seem to find early 2G style, or or really old Mopar v-belt styles; neither do me any good..

 

Thoughts?  I can grab a couple pics shortly.

 

[Rogan]

Here's it installed to what I THINK is gonna be proper.   Orange is going to F+, Green to F-, White to 12V, Black is Ground.

 

[Mopar1973Man]

Why would you wanna do that? 

 

It's best to keep the PCM regulator and the the battery temperature sensor. The reason for the regulator failure is the blue lead has shorted to ground. I've got a write up on how to fix all this... Then just replace the PCM. You'll never have this problem again.

 

Then you need to do the W-T ground wire mod.

 

[Rogan]

Because it's a farm truck that never leaves the farm, it's my old totaled truck (nv4500 24V).  It's not worth a 6-900$ PCM.

 

BTW, the mod to one-wire sits voltage at 14.5V, rock-solid.  Regardless if I turn everything on, stick jumpers to a dead tractor, etc..  So it definitely works as I intended.

Edited September 14, 2019 by Rogan

[Mopar1973Man]

Might be so but you going to be wiping out battery all the time. The whole external regulator idea typically fails with batteries be ruined by undercharged or overcharged. All the old school regulators work off of air temperature under the hood. This why I do not suggest them. If you place a external regulator in a area that is too hot it will undercharge. Then if you mount in too cold of a place it will overcharge and boil the batteries dry. 

[Rogan]

So it is not 'externally' regulated (like an old dodge or ford regulator).  It is internally regulated, just like 99% of the GM alternators..

 

I know what you're getting at, Mike, but it's still not worth the additional expense to replace or repair the PCM in this particular vehicle, unless it's a repair that I could do, myself..  If this were a $8000 road-use truck, then yeah, I'd definitely look at repairing/replacing the PCM.  But it's not, by any stretch of the imagination.

 

[Mopar1973Man]

1 minute ago, Rogan said:

unless it's a repair that I could do, myself.. 

 

Its possible. if you can get the tracer soldered back together again. Its just a switched 12V line typically. Even if you back fed +12V on the blue lead the green lead is still functional. Like when mine fried green lead to the regulator still worked. Just needed 12V on the blue wire. 

[Rogan]

so are they 12V triggered, or ground-triggered regulation?  I mean, which toggles for voltage regulation during operation?

 

[Mopar1973Man]

+12V suppose to come on after tach signal is seen. 

 

Ground regulation starts after tach signal is seen. Like I said you can back feed +12V to the blue wire it should start to function again. Just make sure to put a 5A fuse on that supply wire. 

[Rogan]

9 minutes ago, Mopar1973Man said:

+12V suppose to come on after tach signal is seen. 

 

Ground regulation starts after tach signal is seen. Like I said you can back feed +12V to the blue wire it should start to function again. Just make sure to put a 5A fuse on that supply wire. 

"backfeed" as in after pcm repair?  or tag 12V fused at 5A to the blue wire?

Edited September 14, 2019 by Rogan

[Mopar1973Man]

Backfeed without repairing the PCM. The voltage regulator only controls the green wire on the ground side. Hook up keyed +12V to the blue wire with a 5A fuse.