yeah, i'll take another look at it.

also, in the haynes manual circuit diagram, it shows a "charge" fuse (7.5 amps). i can't find any other reference to it.

 

Wire to the bulb is bad? Take a look at the wiring diagram in the FSM and work backwards from the bulb.

http://www.ncttora.com/fsm/1993/body.../6combinat.pdf
http://www.ncttora.com/fsm/1993/charging/2onvehicl.pdf
6. INSPECT DISCHARGE WARNING LIGHT CIRCUIT
(a) Turn the ignition switch ON. Check that the discharge
warning light is lit.
(b) Start the engine. Check that the light goes off.
If the light does not operate as specified, troubleshoot the
warning light circuit.

 

And you check continuity on all the lines from the alt? Check pin connections. Could be corroded wires? And I mean inside the jacket not just the end, check resistance.

 

i'll bust out the dmm later this weekend. i'll be working on the trailer tomorrow and saturday. good suggestion, rb.

 

Does this help locate the fuse?

http://www.ncttora.com/fsm/1993/body.../2powersou.pdf

 

yes and no. thanks.

i now know that i do not have a charge fuse. great. time to look at the schematic one more time, again...

 

Oy vey! lol.... Sorry for the voltage issues... but if anyone I know is bound to find it quick..........it's you, Ian.... Still, SUX! lol.

I found a place this last week that told me to bring them an MR2 Alternator from Pick-Your-Part and they'll restore it and get it to put out 120A for 80$....... Plug and play... I think that's pretty good, no? lol.

You just reminded me that I need to double check my 4WD light in my dash..... I'm not sure it's working, although it did work after the conversion to Manual Hubs... Anyway, thanks for posting this, it's got me wanting to dig into a couple things/rewire more than I was during the Fuse Block install.

 

I suggested to disconnect the alternator..... I think you think I said to disconnect the battery...

 

yep. i re-read. d'oh!

i can try it, but i doubt it'll have any effect other than running the truck on battery alone. (at least it's easy to do with my bus-bar setup!)

thanks

 

I threw you off with the burned bulb

 

haha, yup

 

so i just did a quick check with the voltmeter.

(key in "on" position)

c3 is getting positive at the plug like it should. c4 should be connected to ground, but there's no continuity to a tested ground spot. that means the issue lies somewhere between the plug and alternator. although it's rather hard to track down without a "charge" fuse

 

So what's the plan? You going to fish through all that and add a 'charge fuse'? (Sorry if that's a dumb question.... I'm still learning on the electrical stuff............And, well, I'm so overwhelmed with life at this moment that I'm forgetting over half of what I learn while I'm trying to absorb the 'next step' of the electrical process! hahhahaaha)....

You'll get it, Ian... But, sorry for the drama, it's always sucky, lol.

 

i'm looking through all the wiring diagrams i can find, and based on this one, it should be a straight shot to the alternator. so i either have a bad wire, bad connection, or bad alternator regulator. now taking bets!

for reference. i'm looking through it right now...
http://www.ncttora.com/fsm/1990-1995...es/wiring.html

 

here's what i tested. i'm going to check the continuity of the yellow wire, from 4B to the alternator at L

 

I'm guessing Regulator.... But I don't WANT it to be that as I guess it could reek havoc? Surge? Anyway, I guess fishing through the harness isn't always 'WEEEEEEEE FUNNNN', either, right? lol.

Time to get fishin, eh?

 

aaaand done.

regulator.

so now it's time to get a new one (either alternator or regulator). thanks to rb for the dmm suggestion/reminder.

 

Wait, ......I actually guessed correctly? hahaha. Glad you found it quick. Did you grab a NEW or used Alt. when you slapped that GM in?

 

edit: bought it new... hmmm...

and for anyone wondering, here's the diagram of all the measurements i took to chase it down.

from top to bottom:
•voltage from bulb positive to ground (ruled out ignition fuse circuit)
•voltage across bulb (first test, determined there was no power to the bulb)
•resistance from bulb negative to ground (ruled out the combination meter)
•resistance from bulb negative to "L" terminal on alternator (ruled out wiring)

that left me with the alternator (circuit) as the only culprit

 

"Good deductions, Holmes!".... lol. Man, I need to head to SCROC and take Auto Electrical and Welding classes!!!! lol.