16.4 volts at the battery

[734406pk]

Quote:
I suppose that this test will just confirm that the drop is somewhere between the connector at the bulkhead and the end of the VMR blue wire right? It will show a 1.4 or so voltage drop....And if it DOESNT , then the next step is to measure between the bulkhead connector and something inside the car?

That's right! If we back probe pin 23 on the engine side and we have a low voltage drop, the issue is in the engine harness. If we have a high voltage drop, the issue is somewhere in between the bulkhead connector and the battery positive terminal 

[73440]

Taken from 73 FSM.

And GO PENS !!!

[734406pk]

Perfect! That drawing will make it easy to find!

[shadango]

Taken from 73 FSM.

And GO PENS !!!

AWESOME! Thanks!   (As an aside, and not wanting to clutter up this thread with side bars, I just have to say....Love this forum......most of the stuff I have ever done on this car since 2007 has been made possible only by the great folks on this forum.....whether to just give me the push I need to do something or the complete "how to" info......what did folks do before Al Gore invented the interweb!? LOL)

[734406pk]

Happy to help a fellow E-Body owner!  You are close to finding the problem Shadango!

[xtopfuel]

You have been quite helpful, a true team player 73440

[shadango]

Now on to find the resistance...
Looking at the new engine harness at the bulkhead connector,engine side,  you will see a blue wire on pin 23.
We need to connect the positive volt meter lead to the positive battery terminal and the negative lead back probe the blue wire connector at pin 23. Load the electrical system as before and write down this reading as G.
This test will check the integrity of the engine wire harness ignition power feed circuit. There's a substantial load on this blue wire.

Ok, so I test fitted my back probing at 23 before cranking up , just to be safe.....had that figured out....then started her up , swicthed stuff on etc....and checked the voltage at the battery.....it had dropped to 15.4 or so.

So I figured that my messing with pin 23 was what helped there.....droped .4 volts from my usual 15.8.

Did the test you prescribed, got .7-.8....so I went ahead an pulled tha twire from the harness plug, resoldered the connection, cleaned as best I could (what the hell do you use to clean the bulkhead connections?), greased it up and stuck it all together again...took a while since I had to fight a big rain storm.,..LOL

Anyways, after reassembly I measured again....had a reading still of .8.   Now, if I turned everything off except the dome light (since I forgot it), I got a reading of .6.

Also, before messing with soldering the wire at 23, I also checked for voltage drop between wire 23e and the left plugs on the ballast.....got .2 on the top and .5 on the bottom......if that helps at all. LOL

After all this was done, I am still reading at 15.2-15.4 volts at the battery ---that does make my summit gauge read a lot better rather than pegged....it reads at 15-15.5,

SO SOMEHOW I picked up .4 volts.....maybe it was the wire at pin 23 or maybe not.....   

[734406pk]

Quote:
Anyways, after reassembly I measured again....had a reading still of .8. 

Ok to be sure here, you have 0.8 volt drop at the engine side of pin 23? This reading is with the electrical system fully loaded, yes?

[shadango]

Quote:
Anyways, after reassembly I measured again....had a reading still of .8. 

Ok to be sure here, you have 0.8 volt drop at the engine side of pin 23? This reading is with the electrical system fully loaded, yes?

Yes sir, that's correct.

[734406pk]

OK Great! That reading G shows that there is major voltage drop between the battery positive terminal and pin 23.

Quote:
So I figured that my messing with pin 23 was what helped there.....droped .4 volts from my usual 15.8.
 
There is also a minor voltage drop in the engine harness, but we'll get back to that one later, we want to find the big one first.

 So now restart the car, idle speed 1200 rpm and fully load the electrical system (high beams on etc)as before. Connect you positive volt meter lead to the positive battery post and the with negative test lead, back probe pin 16 on the bulkhead connector-engine side. Write down this reading as H.

 This will test the power feed (fuse link) into the car. With the ammeter bypassed, the entire electrical load passes through this one wire.

[734406pk]

So looking at my fusible link connector I saw that it looked like it had melted a little



I pulled it apart and found this:



I was thinking maybe THAT was contributing to the high voltage reading......
I replaced the spade with a new one...crimped and a little solder....reassembled.

No luck.  Same high readings.

Even disconnected the choke, no change.

Back to the drawing board.

At this point all I can figure is that the problem must be on the bulkhead or dash side of the car.

This pic shows a problem with the fuse link connector. Resistance impedes current flow and generates heat in the process. This issue should be looked into. 

[shadango]

I replaced the connector already.

[734406pk]

I replaced the connector already.

The fuse link has been replaced, understood... What concerns me is this connector show no sign of corrosion. Something else is wrong here.

[shadango]

I didn't replace the who fusible link.....just replaced the spade connector on it.

I am thinuking it was a poor crimp/connection from when it was new maybe.

[734406pk]

I highly recommend testing the voltage drop here (pin 16, fuse link) with the electrical system fully loaded. It just may be the cause of most of the voltage drop measured already.