penick000

I've got a 96 F-150 w/ 5.0 and 5spd but no factory tachometer. My search of the forum turned up a few threads, but none that accurately described how to wire the tach signal wire for these trucks.

I have installed tach's before on vehicles with traditional coils (look like coke cans) w/ the (+) and (-) sides and never had a problem.

On these newer vehicles, where is the best place to pick up the tach signal? Should one of the wires at the coil be spliced into? Is it better to go from the PCM somewhere? Is there a wire in the dash that it could be fed from?

Thanks for any input.

pen

DixieDarkhorse

the coil on these tfi fords are just like those cans, just a different shape, there is still a (+) and (-) on them. all you need to do is splice in the the negative side.

penick000

that's what it appeared to me as well, but I wanted to make sure there wasn't some wire shielding or other odd thing that I wouldn't be aware of.

Perhaps I can pull the wires apart in the connector itself and join there rather than splicing.

It's too bad they didn't leave a wire under the dash somewhere in the harness.

Thanks,

pen

Mustanger

I'd get a wiring diagram first...I bet there is a tach wire in the harness that plugs into the gauges already prewired for the models that have a factory tach...worth looking into could be real easy to access under the dash.

That is the way it is on my 94 Mustang ( has factory tach) The plug has the tach drive wire in it...I just splice into it for my shift light.

Just call me Sean

iTrader: (1)

Definitely try to find a wiring diagram for the instrument cluster. There is a wire for the tach there, you just don't have the cluster for it. My diagrams don't show the cluster.

penick000

Here is what I ended up doing.

The tach comes with 4 wires. The one I purchased used black for ground, red for a KEYED power source, white for a lighting power source and green for the tach signal.

First thing I did was mount the Tach on the dash. My truck is 2wd so the area on the dash above where that switch would be is a perfect spot with room to drill and not hurt anything.

Next I found a power source for my lighting that operates with my dimmer to allow the light in the tach to do the same. I decided to use the power line for the lights on the heater control panel. Here is the pic. This was for the tach's white wire.



I chose to use splice connectors for most of this installation. Here is the white wire tied into the hot side of the heater control lights.



Next I found a source for my Keyed Power supply (only has 12v when the key is in the ON position.) This connector is under the center of the dash. The wire that has keyed power only is the red wire w/ yellow stripe



Here is it with the Red wire from the tach spliced in.



Next I used this metal panel above the clutch pedal for the ground source.




Since I was unable to find a wire under the dash that had a tach signal, I went right to the source with the Tan and yellow stripe wire right at the coil. To do so I had to go through the firewall with my tach's green wire. I sealed the hole in the firewall with silicone to prevent the wire from rubbing its insulation off. Don't forget to use wire ties or tape and keep that and all wires used out of the way of each pedal's full range of motion.



Splice connection with coils tan / yellow stripe wire.



Tach installed and working.



Not sure how many other years this procedure will work with but this should work to help a few others perhaps.

Thanks to those who gave me suggestions.

pen

TJ Johnson

Penick000,
Good ...Nah, GREAT writeup and photos!!!!!
I'm in the same situation with the only difference being I have an automatic.
She's my first Ford truck and in pretty good shape inside and out, I didn't want to bugger the tach or my baby up. Thankyou

TJ

penick000

It's my pleasure. Hope it helps.

pen

BigBlue95

How did u access the dimmer cable for the heater ***** just pop out the cluster?

TheCollector

thanks for the great pics i need to get a tach too i have over revved my engine a few times i cringe every time but im sure it can handle a minor mess up