Author Topic: Struggling to find an electrical short  (Read 4422 times)

Offline ShelbyDogg

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Re: Struggling to find an electrical short
« Reply #15 on: May 25, 2015 - 11:24:10 PM »
Here is a pic from this guy's old post:

Took it from this thread:
http://www.cuda-challenger.com/cc/index.php?topic=101941.msg1008591#msg1008591

Here are some other threads on the pigtail. Can't see the part number on it, but the thread references another thread that had some more info in it.
http://www.cuda-challenger.com/cc/index.php?topic=93909.msg924632#msg924632
http://www.cuda-challenger.com/cc/index.php?topic=81711.msg819398#msg819398

If yours is not there, make one up out of 2 wires, crimp terminals and a diode. Out of my 7 harnesses, I only found one so I just copied it.
 
This was for my 70 and early 71 harness, that used the horn relay as the key-in buzzer. I don't know what you'll need for the other years. 

From the 70 Manual:


The 71 manual only show the buzzer. Does someone have a pic of this buzzer? Does it look like the seatbelt buzzer?
« Last Edit: May 25, 2015 - 11:54:16 PM by ShelbyDogg »
Rob

3 E-bodies, Megasquirt-1v3.0, Edelbrock Pro-Flo-1, Holley C950, FAST EZ-EFI; say no to carbs...yes to throttle bodies

My Pace Car restoration thread:
http://www.cuda-challenger.com/cc/index.php?topic=44869.0





Offline spamtank

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Re: Struggling to find an electrical short
« Reply #16 on: May 26, 2015 - 10:53:26 PM »
Well, I owe you guys a photo.  I found the problem.  Turned out to be the diode pigtail.

Just like the photo Rob shared, the diode leads are uninsulated, and I found mine laying on top of the radio chassis shorting out.

The diode was not broken in half, but did exhibited some thermal trauma. 

So it all adds up now.  Blown fuses over bumps, buzzer going off when it shouldn't, and a quick wiggle of the harness always seemed to fix it.

Should be a quick fix now.
Rick, Manchester, NH
1970 SE 383 2V AT Challenger
1977 M882/W200 Power Wagon
2013 RT Plus 6M

Offline Chryco Psycho

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  • 70 Challenger R/T SE 70 tube Chassis Cuda now sold
Re: Struggling to find an electrical short
« Reply #17 on: May 27, 2015 - 06:22:47 AM »
 :2thumbs:

Challenger - You`ll wish You Hadn`t

Offline spamtank

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Re: Struggling to find an electrical short
« Reply #18 on: May 27, 2015 - 07:54:58 PM »
Here are my photos of the diode.

Sure looks like the gap in the tape was intentional, unless the tape just crumbled in the middle.

I, for the life of me, can't figure out why the lead is un-insulated.

Edit - upon further consideration,  I believe that the original fabric tape crumbled and fell off.  That left the leads exposed.  If you have an original harness with the A01 option, you might be well advised to look for this above the radio and re-tape it.
« Last Edit: June 19, 2015 - 06:41:42 PM by spamtank »
Rick, Manchester, NH
1970 SE 383 2V AT Challenger
1977 M882/W200 Power Wagon
2013 RT Plus 6M