Strange power issue, help?

[shifty]

Got a weird one.

I went to a 1-wire alternator. It's been a couple months since I wired this up, but I had two wires going from the fuse block to the rad support:

1) went to the voltage regulator
2) went to the headlights

I assumed that both would be either a) getting power FROM the battery or b) providing voltage levels TO the cluster (and fuse box).

Apparently I may have been wrong on those assumptions. Now, when I attach the positive battery cable with the key OFF, I see the following:

* "Generator" dummy light comes on. When key is put into "ACC" position, the Generator light turns off. That's backwards of what it should be.

* Radio has 'half' power. When I say "half power", I mean, it comes on and the tuner works, but tapes won't put out sound until I put the key in ACC position - almost like it's not getting a full 12v until key is in ACC

I haven't fried anything yet, I'm just clueless as to what I did wrong. Has anyone seen anything else like this? It's almost like there is 6v of power when key is OFF, and 12v of power when key is ON.

For the record, I have a ground strap from the battery to the inner fender, ground strap from bed to frame, and ground strap from cab to frame. I don't have my strap on from the block to fram or block to body yet, but I'm not sure one missing ground strap would do this.

Any advice is appreciated!

[Palf70Step]

I think you have to cut the brown wire on the back of the ignition switch. I haven't done/finished my wiring, but told that I needed to remove/cut one wire.

[BACKYARD88]

I had the same problem with my truck but it's been so long I can't for the life of me remember what I did to fix it. I need to start writing this crap down.

[Palf70Step]

Don't you need to add a resistor in the wiring for the alternator also?

[shifty]

I don't think I need a resistor for the LS1 alternator on the LS1 engine.

Basically, there are only three power wires:
1 to from alt->batt
1 from starter->batt
1 from batt->interior

I think the brown wire was the one that went from the bulkhead->voltage regulator, so I will track down that wire tonight and cut it, see what happens.

[byrd]

Doesn't the tan wire control the dummy light or send signal to the ammeter? I know it is brown or blue, can't remember right now which ine it is.

[fosheec]

The tan wire goes to the dash, the blue wire goes to the alternator. You splice them. The tan wire is a smaller gauge and acts as its own resistor.

[shifty]

Does the tan wire power the entire dash? Because I'm getting partial power on the cigarette lighter while the 'generator' dummy light is lit.

I still can't figure out why the 'generator light' would stay lit UNTIL the key is turned to ACC position, either.

[shifty]

Bill, you are the man! I went in and looked at things tonight before firing the engine up, and after unravelling the wire bundle, I noticed that there was a thin brown wire I'd spliced in there - I cut it, and all of my electrical woes went away. Apparently, that needed to be hooked up to a switched outlet. Basically, I was dumping battery power into the dash and it was enough that other things inside the truck were getting power through that.

So, yep, when moving to a one-wire alternator, if you have the non-tach/non-vacuum dash, I would just delete the brown wire.

I owe you one, Bill

[BACKYARD88]

Glad you got it figured out!