87 Ranger Tachometer Wiring

[gtarplaya2k]

Hello, I have been searching everywhere on google trying to figure out the wiring to the instrument cluster on my 87 ranger. My tachometer hasn't worked since I bought the truck. Since then I have replaced the instrument cluster but still no luck. So what I'm trying to do is just run a wire from the tach signal wire on the cluster to the green wire coming out of the dizzy. Problem is I cannot figure out which wire I need to connect to on the back of the cluster. Any help will be greatly appreciated as this truck is a rats nest of wiring the guy before me had going on, but its almost all squared away now just this one last issue.

 

[Hitchner2009]

The wire that you need to be going into is DARK GREEN/YELLOW. Meaning a Solid dark green wire with a yellow tracer. This will power your tachometer

 

[gtarplaya2k]

Thats the wire at the distributor correct? Does it stay the same all the way to the back of the cluster?

 

[Terry]

Thats the wire at the distributor correct? Does it stay the same all the way to the back of the cluster?

Yes it does

 

[gtarplaya2k]

Awesome I will try this out hopefully it will fix my issue

 

[gtarplaya2k]

so i ran a new wire from the back of the cluster to the distributor and the truck wouldnt start so i added the old grn/yel wire coming off the distributor back into the circut with the new wire. Truck started up fine but still no tach, put in the old cluster just to double check and nothing.

 

[Terry]

so i ran a new wire from the back of the cluster to the distributor and the truck wouldnt start so i added the old grn/yel wire coming off the distributor back into the circut with the new wire. Truck started up fine but still no tach, put in the old cluster just to double check and nothing.

Do you have a dwell meter or a volt meter? You should be able to see voltage at the wire. Did you meter to see if the old wire had a break in it? I believe you posted earlier that the truck had a tach from the factory.

 

[gtarplaya2k]

I have a volt meter and yes the truck has a factory tach. since all other gauges work i figured I could rule out a ground issue, so I assumed that the signal wire was the issue which from my knowledge is the grn/yel wire coming off the distributor. I didnt think that this wire had anything to do with the truck being able to start rather just to send a pulse to the tach. Which leads me to think maybe the previous owner screwed up the wires to the distributor since the harness connector looks new maybe he placed them in the wrong order. This is another reason why I was trying to just find the schematics for the cluster and the distributor.

 

[Terry]

You have the correct wire. I just put a tach cluster in my 87. Good luck with a good diagram. I looked everywhere and

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[Terry]

You have the correct wire. I just put a tach cluster in my 87. Good luck with a good diagram. I looked everywhere and found bits and pieces. The green wire is used in more places.

Sent from my SAMSUNG-SGH-I337 using Tapatalk

Sent from my SAMSUNG-SGH-I337 using Tapatalk

 

[gtarplaya2k]

ok so how can i test the wire with a volt meter what should it be reading? Also is there a separate ground wire for the tach, or any other wires that would be causing this issue?

 

[Terry]

From what I believe the black wire with the white stripe next to the signal wire should be a ground. As for testing the signal wire, set your meter to dc volts. Ground the black wire. If you are doing this alone connect a clip lead to the red wire on your meter and the other end to the signal wire. Turn the motor over and the meter should move up and down between 0 volts and 12 volts.

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[Hitchner2009]

Here is the wiring diagram that you need to complete your repair.

 

[Terry]

I am not sure that this diagram is correct for the year? This diagram has a speed sensor and I am not sure if this 87 or my 98 have a speed sensor?

 

[gtarplaya2k]

The blk/wht wire you spoke of as the ground on mine looked blk/yel checked it anyway and it's grounded. However, when I tested the grn/yel wire to see if it went to 12 volts when cranking it only varied to 0.02V not sure if that's because the pulse is so fast that the digital volt meter cannot detect it or if the wire just isn't getting what it's supposed too.