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Electrical Wiring Struggles!

  • Thread starter Thread starter bwcbizzy
  • Start date Start date Aug 3, 2023
B

bwcbizzy

New Member
Aug 3, 2023
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Aug 3, 2023
#1
  • Aug 3, 2023
  • #1
Hey all - Recently picked up a 1989 GT, 5 speed and struggling with some electrical challenges.

Issue # 1: My ignition wire (pink/white) has been very poorly converted to a yellow wire, which now goes straight down to the neutral safety switch, which I found unplugged. When it gets there, it is just shoved into the back of the connector and pops out quite easily. Guessing this was done by previous owner as some sort of bypass because I don’t need to push the clutch to start.

From the diagrams, it looks like the wire is supposed to go to the switch, but not sure where it should actually be connected as the rest of the wires appear to be correct. I would like to get it to the right place and connected correctly, and also plug the connector into the clutch safety like it should be. Included pictures of the connection and the empty plug space/other connector for reference.

View attachment 712729View attachment 712730View attachment 712731

Issue #2: Reverse lights don’t work. Rest of tails and functionality are good. Checked bulbs, changed switch on transmission, changed harness to the switch, checked fuse, all looks good. Anything else obvious to check before I break out the meter?

Issue #3: high beam indicator stays on all the time. Prior owner changed headlights to some odd LED ones. Based on research, I was able to switch some of the wires in the hi/lo/flash to pass, so they actually function correctly with the stick and all the beams are working properly. Only issue is the indicator is always lit. Research suggests possible grounding issue or perhaps dimmer switch, anything else to be checking that may cause the issue?

Sorry for the long post, electrical isn’t really my forte and I’m learning a lot of this as I go. Tried to do as much research as possible but I’m a bit stuck on some of these. Any recommendations are appreciated!!
 

limp

wrap a little cheese around it and its a done
5 Year Member
Oct 4, 2020
5,457
2,889
173
Florida
Aug 4, 2023
#2
  • Aug 4, 2023
  • #2
PUrchase one of these troubleshooting manuals.... They are very helpful

1989 Ford Mustang Electrical Vacuum Troubleshooting Manual | eBay

Find many great new & used options and get the best deals for 1989 Ford Mustang Electrical Vacuum Troubleshooting Manual at the best online prices at eBay! Free shipping for many products!
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Reactions: General karthief

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
27,829
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polk county florida
Aug 4, 2023
#3
  • Aug 4, 2023
  • #3
Pic link don't work
 
B

bwcbizzy

New Member
Aug 3, 2023
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1
Aug 4, 2023
#4
  • Aug 4, 2023
  • #4
Sorry trying images again!
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
27,829
10,509
203
polk county florida
Aug 5, 2023
#5
  • Aug 5, 2023
  • #5
So the yellow wire with the crimp connector is spliced into the white/red stripe wire?
Let me dig up my majic book when I get to the garage. It should show this in the clutch safety switch wiring.
 
B

bwcbizzy

New Member
Aug 3, 2023
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1
Aug 5, 2023
#6
  • Aug 5, 2023
  • #6
Thanks so much! So it’s weird, it’s not actually spliced in. It just has a spade connector crimped at the end of the wire which is jammed into the switch connector next to the other wires that are supposed to be there. It pulls right out if you hit it with your foot or something by accident. Very shoddy stuff!
 

vferrizz

Member
Oct 23, 2020
64
10
18
Fleetwood, PA
Aug 6, 2023
#7
  • Aug 6, 2023
  • #7
Definitely would not trust that spade connector set up. Loose electrical connections cause weird stuff. My 66 Chevelle would just die randomly for no obvious reason and kicked my butt for months. The cause was the +12 VDC supply to my MSD box was from a wire that was connected to a spare terminal on my fuse box using a spade connector. Apparently, it was not a firm connection all of the time. I hard wired it to a proper +12 VDC feed from the battery and car has been running like a champ ever since.
 
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