Different Alt light stays on question

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   Yes, we have searched with the terrible search engine here and using Google, but have not found this situation.
Alt light does not light when first turning the key. Alt light does come on when Alt energizes and starts charging. Alt light stays on while car is running.

1971 Hornet 232 six.

New Battery, load tested and charged, currently holding 12.75 volts at rest.

New Alternator.  Chevy, 12si just came back from Advanced where tested good.  On the car produces a solid 13.75 when car is running.

Wiring, Orange wire to white alt connector 1, red alt connector 2 to battery charge terminal on alt, battery lead to battery post on alt.

Alt light works, because it stays lit when car is running.  OIL light comes on as should on first notch on ignition key.On starting the light below oil energizes and lights as should.

   We have tried the wiring suggestions on the forum as well as the diagrams from Mad.  We believe it is in the wiring to the alt.  We have confirmed continuity of wiring from alt to dash, all good. Looking for suggestions.  Additionally the dash printed circuit board has been replaced and has been tested for continuity and is working per specs.

Ideas appreciated.

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jfulton540 Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Fan Joined: Oct/04/2015 Location: Illinois Status: Offline Points: 9	Post Options Post Reply Quote jfulton540 Report Post Thanks(0) Quote Reply Topic: Different Alt light stays on question Posted: Nov/28/2015 at 12:45pm
	Yes, we have searched with the terrible search engine here and using Google, but have not found this situation. Alt light does not light when first turning the key. Alt light does come on when Alt energizes and starts charging. Alt light stays on while car is running. 1971 Hornet 232 six. New Battery, load tested and charged, currently holding 12.75 volts at rest. New Alternator. Chevy, 12si just came back from Advanced where tested good. On the car produces a solid 13.75 when car is running. Wiring, Orange wire to white alt connector 1, red alt connector 2 to battery charge terminal on alt, battery lead to battery post on alt. Alt light works, because it stays lit when car is running. OIL light comes on as should on first notch on ignition key.On starting the light below oil energizes and lights as should. We have tried the wiring suggestions on the forum as well as the diagrams from Mad. We believe it is in the wiring to the alt. We have confirmed continuity of wiring from alt to dash, all good. Looking for suggestions. Additionally the dash printed circuit board has been replaced and has been tested for continuity and is working per specs. Ideas appreciated.

vinny Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Jan/05/2012 Location: Calgary Status: Offline Points: 2837	Post Options Post Reply Quote vinny Report Post Thanks(0) Quote Reply Posted: Nov/28/2015 at 5:17pm
	What does it do when you put the little orange wire to ground? and when it is disconnected ? The way I see it with the key in the on position the light should come on and that would prove the light circuit is good.

vinny Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Jan/05/2012 Location: Calgary Status: Offline Points: 2837	Post Options Post Reply Quote vinny Report Post Thanks(0) Quote Reply Posted: Nov/28/2015 at 5:21pm
	Orange wire grounded and the light should come on.

jfulton540 Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Fan Joined: Oct/04/2015 Location: Illinois Status: Offline Points: 9	Post Options Post Reply Quote jfulton540 Report Post Thanks(0) Quote Reply Posted: Nov/28/2015 at 8:29pm
	Using a test light through the orange wire turns the Alt light on. ALT light and wiring are functional. New ground battery to engine block. Engine to chassis ground on passenger side replaced onto fresh prepared bare metal. Block to Chassis ground new. Dash ground is good. Ground to headlight switch is good. Ground to gauges is good shows engine temp and fuel level. Turn signals work on dash and outside of vehicle. Brake lights work. Headlight switch is good, adjust dash lights well, turns on dome light and works the headlights and parking lights. Cigarette lighter works. Engine runs, smooth and starts instantly. 71, so no step down to the dash, the temp gauge handles the duty. All fusable links intact. Frustrating situation.

vinny Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Jan/05/2012 Location: Calgary Status: Offline Points: 2837	Post Options Post Reply Quote vinny Report Post Thanks(0) Quote Reply Posted: Nov/29/2015 at 6:48am
	If you have proven the light circuit is good it looks to me to be alternator. The light should come on with key in on position. It should charge more than 13.75 volts. Try another one. I get mine from the junk yard for about $30, usually looking new with a recent overhaul tag. The Delco CS130 is what I go for and it will probably involve a pulley swap from serpentine to V type. There are lots of different mounting configurations so I get the lugs 180 across and 6.6" apart. You would of course need the connector with it. L to lamp (orange) and S (sense) to where you want to sense the voltage, sometimes on the GM donor found hooked to the output terminal. The P doesn't get used and the I/F doesn't need to be used, at least from what I read on the Internet about the swap. Early 90's GM is where to look.

vinny Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Jan/05/2012 Location: Calgary Status: Offline Points: 2837	Post Options Post Reply Quote vinny Report Post Thanks(0) Quote Reply Posted: Nov/29/2015 at 8:18am
	I'm not up on the technical stuff on the inner workings of these alternators but should there not be, alternator at rest, somewhat of a continuity between the #1 terminal and ground? Ohmmeter reading?

jfulton540 Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Fan Joined: Oct/04/2015 Location: Illinois Status: Offline Points: 9	Post Options Post Reply Quote jfulton540 Report Post Thanks(0) Quote Reply Posted: Nov/29/2015 at 12:34pm
	Alt is brand new, not a reman. It passes all bench tests. Alt has been taken to two different parts stores and tested on bench and spinning. It passes, Alt works perfect in Camaro reads up to 14.28 volts when needed and averages 13.75 volts, it is not the alt but something in the AMC. We will keep chasing it, just looking for some ideas.

vinny Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Jan/05/2012 Location: Calgary Status: Offline Points: 2837	Post Options Post Reply Quote vinny Report Post Thanks(0) Quote Reply Posted: Nov/29/2015 at 2:56pm
	Does the Camaro also have a light and it worked normally with that alternator?