Few more questions. Seeing that relay coil needs only a fraction of an amp to trigger then can I use a 1 or 2 amp fuse in my switched circuit instead of the 10A I have in there now? Also, would I need an inline fuse somewhere along the feed wire going from the relay to the + battery terminal to protect the regulator or does the relay substitute as a fuse (or am I too paranoid)? Lastly, If my regulator is well grounded is there any reason why I cannot run the relay ground to one of the mounting screws on the regulator?

 

Uhh ...

No.

*dry* Relays are not fuses; if used as such, the end result is usually fire and damage.

The switched circuit wire should be off a currently fused circuit. Problem solved. (You could even tap the 12V feed to the coil if you wanted to). IDEALLY you'd use the old regulator 12V feed, or the old 12V line run to the alternator field.

The one to battery positive needs its own fuse; I'd start with 10A which should be plenty for the field coil even at full drive.

(Math says that at 6 ohms, which is about what mine measures as, should pull a max of 2.5 amps. 10A gives some extra in case of an inductive kickback from the field coil.)

The one to regulator should also be able to feed the field coil. That should help both of them.

Run the FRM to the old field wires off the PCM.

Should take care of all of it there.

RwP

 

OK. My switched circuit is already fused with a piggyback. I can add one to the battery +. Thanks. I don't think my FRM works. I connected it initially using their cheesy spade terminals and butt connectors and it did not shut down the CHECK ENGINE light. Those spades weren't the right connections for that module. I was going to try it one more time and actually solder the wires to the module and see if that works. Alternatorman said the FRM doesn't always work (in 10-15% of the cases) depending on what is wrong with the PCM.

 

UPDATE # 7,495,279

Installed the relay kit for the regulator. Soldered every splice and terminal and finished them with dielectric grease and heat shrink. Loomed it all, dressed it out nicely. Works perfectly fine. No shakes whatsoever.

Getting 14.05v on the battery at idle. No change with load (fan, lights, etc.). Maybe a tad low and I can adjust the regulator if I want but I'm thinking 14.05v is fine and will leave it alone. Y'all agree?

 

I think 14.7 is ideal, however, anything over 13 is going to charge the battery. If voltage doesn't drop below 14, regardless of load, I think that will be perfectly fine.

 

OK. I'll keep an eye on it. Odd that when I ran the regulator off the fuse box in the cab I was getting 14.4v and now that I run it from the battery thru a relay I'm barely scratching 14.0v. I can adjust the regulator but would rather not pull it off to get to the adjustment on the back. It's tucked away pretty good. Any issues going forward and I'll goose it a bit. But knowing my OCD, I'll probably do it anyway.

Thanks HeyYou for the external voltage regulator recommendation. I preferred that option versus sending my PCM back. That would have been my third PCM reman replacement and I just did not want to mess with it anymore seeing the rest of the PCM worked perfectly fine. Seems one never knows what to expect from 27 year old remanned PCMs. It appears they all have issues. And it remains that Chrysler are idiots for putting the voltage regulator in their PCM. Has to be one of the dumber things they've done. Oh, well.

 

Well, it didn't take long for my OCD to kick in. Went back out and adjusted that regulator. Getting 14.65v now. That's better.

The FRM does not kill the CHECK ENGINE light.

 

LOLOL...... You remind me of my wife. She is quite picky about various things as well.

I *think* you also need the wiring from the PCM hooked up, even though it isn't doing anything, for it to turn off the CEL. Verify that before doing it though. Wouldn't wanna be responsible for smokin' anything in your electrical system.

 

According to Alternatorman's video, the two original field wires that came off the alternator go on each end of his module thingy (orientation does not matter, doesn't need grounding). See vid attached. Maybe you see something I don't. Wouldn't be the first time.

Skip to 5:45 if you're impatient.

 

Ah, yeah, the FRM module (the part that is supposed to fool the computer into think its actually doing its job) only works depending on failure mode of the internal regulator..... So, your failed in a way that the FRM module isn't going to solve........