Step by step guide for idiots ( idiot, me )

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nodemon said:
Test light lit, but very dim..
Light went out when "dome / cig lghtr" fuse removed.
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Ok put the fuse back in so the test light comes back on and go through process of elimination until the light goes back out. I'd probably pull the dome light bulb since they're easy to get to. If your test light goes out, then you know the draw is most likely coming from the dome light part of the circuit. Your dome light is switched on and off by your door switches. I'm guessing this may be where your problem is. There is a chance that one of your door switches isn't opening and closing contact completely.
 
nodemon said:
Battery is 10v - 11v right now.. Connection at alternator stud is same.. as well as link at bulkhead. No lights work, interior or exterior... Weird, just out of the blue, my door buzzer went off for about 10 seconds, then stopped...
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Grab the firewall connectors and giggle them while pushing them in. Then see if you have power.
 
1. "Battery Power"
a. Black wires are sometimes grounds, but most of the time they are some sort of main feed.
b. When the battery is hooked up, all of these wires shown below are hot. Most are not protected by fuse or circuit breaker. Ground one of them down stream of the fusible link and with a bit of luck the link will melt before any more serious damage occurs.
1735346473641.png

Measure voltage at any one of them and it should be the same voltage as measured at the battery under the same conditions, especially with key off, lights off.
Ammeter is centered because there is no current flowing in or out of the battery.

When the key is held in start, current flows through the starter and ignition 2 wires. The ammeter will show this current as discharge.
1735344415139.png

Power through start wire S2 will turn the relay on connecting the brown S5 wire to the battery wire A1A. This in turn powers the solenoid in the starter.
The starter solenoid and starter require a lot of current. So much current they will temporarily draw battery voltage down to 10 or 11 Volts. If you measure only 11 Volts during cranking that's OK.

Use this diagram above as a pictorial to go with everything @67Dart273 wrote above. Take your finger and follow along the circuits he describes.

2.
11 Volts across the battery with the key off is a discharged battery. Check the acid level (if it has caps) and continue to charge or maybe its toast. Anyway it needs to be charged from a charger. If the engine starts with a low battery it will suck as much juice as it can from the alternator. You will see the ammeter swing to the upper end of the Charge range on the little meter. Its not marked in red for your year and model but it should be. Run that 20 minute break-in with that much current flowing and at best the connections in the alternator to battery circuit will be melted. On some models the ammeter will also be heat damaged and on most so will the bulkhead connectors.
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^^Don't let this be you^^



Last tip.
Bolt this up.
It gets hot and you don't want this shaking around after the engine starts. You'll get burned, It will get broken, Murphy will laugh his *ss off.
1735343313773.png


I can not over emphasize how important it is to route and support wires so the connections are not stressed or in a location to get pinched and grounded.
 
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nodemon said:
Battery is 10v - 11v right now.. Connection at alternator stud is same.. as well as link at bulkhead. No lights work, interior or exterior... Weird, just out of the blue, my door buzzer went off for about 10 seconds, then stopped...
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You may be losing all power when a load is applied, due to a bad connection. Pick a problem and run it down.

Do the headlights work? They are powered off one of the first branches off the ammeter circuit. Here is a simplified diagram of that part of the wiring


amp-ga18.jpg

Notice that the "light switch" (this is ONLY for headlights) comes off the "welded splice" which is in the black ammeter wire up behind the cluster. This is why I had you check at the alternator. If you have a loose connection at battery post clamp---bad battery cable, bad connection at starter relay "big stud," the fuse link, or the bulkhead connector where the "big red" and 'big black" go through, you may lose power. Also notice the ignition switch is fied power off that splice.

IF the lights work, then pull out the ignition switch connector and get your manual, look up the pin connections for the ignition switch connector. See if you have power going in and out of the switch with the key in "run." That power then goes out through the bulkhead, and feeds underhood loads as I mentioned earlier
 
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The 72 ign switch connector This is up under the dash going into the column. You may need to remove the small trim panel under the column to get enough slack.
Top wire, S2-12Y (no. 12, yellow) is the "start" wire and should be hot with key twisted to start.

Next, Q2-12BK is accessory, should be hot either in "run" or "accessory" position of key

J2B is "ignition run" and is hot ONLY in "run." This is the DarkBLue that feeds out through the bulkhead to the ballast, the VR, and the light blue to the alternator field

J3, IGN2, is BRown and is hot in start just like the start wire, but a separate switch circuit. THAT is what powers the ignition during cranking and feeds out to the coil+ side of the ballast resistor

J1-12R is a no 12, RED and is the main power feeding TO the ignition switch. HOT all the time and NOT fused except for the fuse link. BE CAREFUL

72ignsw.jpg
 
LOL. Just had a nice conversation, turns out the body battery ground was disconnected, and pretty much stopping EVERY thang
 

67Dart273 said:
LOL. Just had a nice conversation, turns out the body battery ground was disconnected, and pretty much stopping EVERY thang
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Again, can't thank you enough for the time and info... The simplicity of the issue is sometimes hidden by the ignorance of one, me..!
 
Everything seems to be on track again... To all that chimed in, offered advice and help, THANKS..!! As always, MUCH appreciated...!!
 
Great read to see how you folks jumped in to help Mr. nodemon! All helpful advice and supporting one of our own. Well done to all.

Can't wait to read how Mr. nodemon is enjoying his new ride. Won't be long!
 
nodemon said:
You're right... Just a simple ground..!
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If I were you, I'd go over every connector and take them apart, clean them and put them back together as well as find every ground, remove them, make sure the connection is good and clean and down to bare clean metal.
 
67Dart273 said:
LOL. Just had a nice conversation, turns out the body battery ground was disconnected, and pretty much stopping EVERY thang
Click to expand...
The reason everyone needs a volt meter. I have one in all my cars trunk. The first test I do is remove the neg, cable, test the battery for above 12.75 volts and then check the neg. cable to engine and body ground. Also check aftermarket clamps for corrosion, by probing the clamp to the connecting wiring. 95% of my issues are found during these three tests.
 
ESP47 said:
Glad you got it figured out!

The draw that was draining your batteries is gone as well?
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Another dumb, non thinking over look by me... The draw on the dome fuse was because my doors are off and the plungers were out...lol
 
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