Summit Tach And Shift Light Wire Up

[NewToFord]

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]

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

 

[NewToFord]

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

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

 

[jrichker]

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

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

 

[NewToFord]

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]

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.

 

[NewToFord]

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]

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...

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