Electrical Help with "72" Jimmy
 

I hope someone can help me ....

I have a 72 Jimmy that I can't seem to get the dash Voltage gauge to work. Does anyone happen to have a wiring schematic they could email me. This would help me a great deal to possibly trace the wiring problem. I have tried replacing the the gauge with no success,and i am getting voltage on one side of the gauge. Any help would be appreciated
please email to: cvladski@aol.com
Thanks..
Vlad:gmc: :banghead:

Check your fuses .(not in fuse panel) One is near battery-small black wire with a fuse holder inline (4amp)-it then goes to other side near voltage reg. where there is another just like it. Hope this helps.

Every one of these trucks I've ever seen, that guage was dead. It may actually be the guage and not your wiring.

Brian

The one in my 70 blazer is dead like yours but the one in my 71 blazer works great. start it up for the first time in a hile and it jumps up there then settles back down. But my 70 I cannot get to to work let me know if anyone figures this out. Had the same problem with a 75 put in a new guage/printed circuit and still got nothing

Here is a link to wiring diagrams.

Jim

http://www.geocities.com/chevroletc1070/wiringdias.html

Electrical Help with "72" Jimmy
 

I have had to troubleshoot and repair quite a few of the 67-72 style factory ammeter setups. The ammeter is a shunt circuit that basically parallels the charging circuit wire going to the alternator.
Unforfunately, most of the GM manuals I have seen show only the warning light circuitry and not the ammeter. I have created an Autocad drawing that shows how I believe the original wiring was done. I have used this diagram as a guide to solve amp gauge woes on several vehicles. I can e-mail it to anyone who would like to see it.

I am planning on converting the drawing to an image file so I can post it. As it stands now, it does not convert to scale quite right and it is difficult read as an image file, but it looks good with an Autocad viewer.

Sorry for the longwinded message.

Let me know if you want the .dwg file.

Darrell

Thanks for all of the suggestions and tips. Turns out it was the simplest of all probs. I just didn't realize that there are fuses in the small acorn shaped connections that run from the battery to the regulator. thanks (Jhow66)

Darrell,

Please send me the .dwg you have made.

I have converted my POS to a one-wire setup, and the amp guage is way screwy. (I know Ive bypassed the shunt) Perhaps your drawing will help me figger out how to modify it, so it works for my setup.

dahatetank@yahoo.com

Thank you.
-Marty

Could you please send me the file? I have the same problem.
fruitloops@charter.net