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Electrical Florida 5.0 Gauges wiring question

  • Thread starter Thread starter africansnowowl
  • Start date Start date Jul 21, 2020

africansnowowl

Active Member
Apr 29, 2020
82
35
28
San Antonio
Jul 21, 2020
#1
  • Jul 21, 2020
  • #1
I bought a basic bezel with turn signals from Florida 5.0. Put Autometer Phantom gauges in, and got them all wired up. The instructions from Florida 5.0 are pretty vague about wiring the alternator wire. It basically just says jump it to a 12v switched. Looking at the back of the stock cluster, it looks like the alternator wire (red/lt green), goes to the "amp" light socket on one side of the bulb. A resistor connects it to the lt green/red wire, which appears to be "ignition switch to alt reg". That wire doesn't have 12v on it with key on though. Anyways I pulled that resistor out of the bulb socket and had those two wires splice together with the resistor in-between. So basically splicing pins 5 and 6 together with the factory resistor connecting them together. Does that sound correct?
Also on the subject of gauge wiring, can I use any 12v key on power source for the gauge power(not the lights)? I found a few things that go into the stock cluster that have 12v key on, such as the tach signal and warning lamps feed. For the lights I just used the brown wires in the headlight switch which I have already tested to work.
 

Blown88GT

Founding Member
Nov 13, 1999
2,283
524
164
Palm Beach Gardens, FL
Jul 21, 2020
#2
  • Jul 21, 2020
  • #2

1988 Mustang Electrical & Vacuum Troubleshooting Guide (EVTM)

File is too large to upload. Here is link to it on my Google Drive. View: https://drive.google.com/open?id=1on5czXKmpETzxUggWTGtoUuVkJT2UUxN
www.stangnet.com
 

africansnowowl

Active Member
Apr 29, 2020
82
35
28
San Antonio
Jul 21, 2020
#3
  • Jul 21, 2020
  • #3
Thank you for posting that. So it looks like I was correct in the way I wired the alternator wire. Anyone know how important that 500 Ohm resistor actually is?
 
F

fox_3

Member
Dec 30, 2005
2
1
13
Franklin TN
Sep 28, 2020
#4
  • Sep 28, 2020
  • #4
Hello there - I'm installing a classic dash gauge cluster with autometer ultra lights and I am having the same issue. Classic dash instructions are equally vague on how to re-excite the alternator. Did connecting pins 5-6 work for you? And did you leave that connection in place or just one-time to get it going?
 

africansnowowl

Active Member
Apr 29, 2020
82
35
28
San Antonio
Sep 29, 2020
#5
  • Sep 29, 2020
  • #5
Yes, connecting pins 5 & 6 with the resistor in-between worked for me. I still don't know if that resistor is actually needed or not though.
 
F

fox_3

Member
Dec 30, 2005
2
1
13
Franklin TN
Sep 29, 2020
#6
  • Sep 29, 2020
  • #6
Thanks. I have a left over ignition wire from the classic dash wiring harness. I'm wondering if I can't just connect that to the Red/Light Green wire. That wouldn't have a resistor, but I think I'll give it a shot.
 
N

NXcoupe

Active Member
Dec 3, 2009
80
27
28
Dayton, OH
Oct 1, 2020
#7
  • Oct 1, 2020
  • #7
Needs the resistor to allow the alt warning light to operate and the alt to charge. I have to do this on every holley digital dash I install. 05 up are easier but require computer pwm control.
 
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