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Summit Tach And Shift Light Wire Up

  • Thread starter Thread starter NewToFord
  • Start date Start date Apr 17, 2014
N

NewToFord

Member
Oct 7, 2008
318
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CT
Apr 17, 2014
#1
  • Apr 17, 2014
  • #1
I bought the summit tach and shift light combo. Has anybody wired one yet? It's 4 wires. I searched and didn't find anything. I also have a msd 6al. I'm not sure if that makes a difference or not. Thanks
 

RangerJoe

I leave the horn on while driving
15 Year Member
Apr 26, 2010
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Apr 17, 2014
#2
  • Apr 17, 2014
  • #2
Did it not come with instructions? I would imagine you have a 12v source, a ground, a tach signal wire (can go so output on msd box) and the 4th is probably an power source for the back lighting. This is all just speculation without seeing it in person. I bet summit has instructions on their website.

Joe
 
N

NewToFord

Member
Oct 7, 2008
318
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Apr 18, 2014
#3
  • Apr 18, 2014
  • #3
RangerJoe said:
Did it not come with instructions? I would imagine you have a 12v source, a ground, a tach signal wire (can go so output on msd box) and the 4th is probably an power source for the back lighting. This is all just speculation without seeing it in person. I bet summit has instructions on their website.

Joe
Click to expand...
ok anybody have a link to what wires I can pick up for 12v source, etc
 

jrichker

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#4
  • Apr 19, 2014
  • #4
NewToFord said:
ok anybody have a link to what wires I can pick up for 12v source, etc
Click to expand...
See
The MSD (May Suddenly Die) 6AL has a wire for the tach. See https://www.msdignition.com

The radio ha a dimmer wire you can for the tach illumination, I believe that it is Red/lt blue.

Red/ green wire on the ignition coil for tach power.
Or
Diagram courtesy of Tmoss & Stang&2birds

Ignition switch wiring

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/ Everyone should bookmark this site.

Complete computer, actuator & sensor wiring diagram for 91-93 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

O2 sensor wiring harness
http://www.veryuseful.com/mustang/tech/engine/images/mustangO2Harness.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

TFI module differences & pin out
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

Fuse box layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif

87-92 power window wiring
http://www.veryuseful.com/mustang/tech/engine/images/mustang87-92 PowerWindowWiring.gif

93 power window wiring
http://www.veryuseful.com/mustang/tech/engine/images/mustang93PowerWindows.gif
 
N

NewToFord

Member
Oct 7, 2008
318
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Apr 19, 2014
#5
  • Apr 19, 2014
  • #5
Wired everything up but I am not getting a tach signal. The tach just reads 0. I have a msd 6al, and I wired the green tach wire to the tach output on the msd. Any suggestions?
 

larrym1961

5 Year Member
Dec 18, 2010
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Apr 20, 2014
#6
  • Apr 20, 2014
  • #6
If everything is wired up corrrectly your Tach should work, unless you got a faulty Tach? I bought a Summit digital water gauge a wile back and the temps read about 40 degrees cooler compared to my Auto Meter mechanical water temp gauge. I am not sure I would trust the Summit brand gauges or not.
You can call Summit Tech, 1-330-630-0240 and maybe they can help you out or give you a reason why their Tach is not working.
 
N

NewToFord

Member
Oct 7, 2008
318
1
19
CT
Apr 20, 2014
#7
  • Apr 20, 2014
  • #7
Found the problem. I have the MSD harness. It was not plugged in. I think my tuner bypassed it, because we were having spark issues, which was the TFI. Tach works, it does bounce around at idle. Like 850, 870, 900, 850, but I think thats normal with a big cam isnt it? Also where did you guys pick up your red power source? I tried the ignition, but I can't splice a 20 guage wire into a 12 without soldering. And I dont have a sodering gun.
 

jrichker

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Apr 20, 2014
#8
  • Apr 20, 2014
  • #8
Time to spend some money on tools or you can tap into the red/green wire on the ignition coil.

MSD wiring:




Here's how to make a proper wire splice...


You guys with idle/stall problems could save a lot of time chasing your tails if you would go through the Surging Idle Checklist. Over 50 different people contributed information to it. The first two posts have all the fixes, and steps through the how to find and fix your idle problems without spending a lot of time and money. I continue to update it as more people post fixes or ask questions. You can post questions to that sticky and have your name and idle problem recognized. The guys with original problems and fixes get their posts added to the main fix.

It's free, I don't get anything for the use of it except knowing I helped a fellow Mustang enthusiast with his car. At last check, it had more than 134,000 hits, which indicates it does help fix idle problems quickly and inexpensively.
 
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