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TKO 600 Speedometer issue

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Old Oct 22, 2010 | 05:02 PM
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Default TKO 600 Speedometer issue

I got my TKO 600 installed with the digital Speedometer plug and the manual speedo blockoff. I ran the positive wire to my "SIG" tab on the back of my Autometer Phantom Digital Speedometer, and grounded the other wire. It is reading about 100 MPH at 25 actual MPH.. Anyone have any experience with this type of setup? I have done quite a few searches on here and google, with no results..
Thanks!
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Old Oct 22, 2010 | 06:49 PM
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There should be 3 connectors on the back of the gauge. A + lead a - lead and a signal. The signal one should be coming from the transmission. The positive lead should be 12 volts and the - should be a ground. On my T56 there are 2 leads from the transmission. A signal lead and a ground. I ran the signal lead to the gauge and the other to the ground.
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Old Oct 22, 2010 | 06:54 PM
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I have the ground wire from the transmission grounded to the body. Does it need to be connected to the ground tab on the speedometer?
The Speedometer has seperate power and ground to it..
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Old Oct 22, 2010 | 07:05 PM
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The body is not a good ground. I grounded mine to the transmission crossmember. My gauge ground is to the harness ground in the dash wiring.

Is there a calibration mode for your speedo. I run an Autometer electronic speedo and it was running way high until I went through the calibration process.
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Old Oct 22, 2010 | 07:47 PM
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I am sure my body ground is good, but I will relocate to frame.
I will also look for information on how to calibrate it. I was not aware that was possible. It is a Phantom 5" AutoMeter Digital Speedometer. Thank you for the help.
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Old Oct 22, 2010 | 07:56 PM
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I have found the procedure. Just have to find a place where I can judge 2 miles distance accurately.... lol! Highway I guess...
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Old Oct 22, 2010 | 10:19 PM
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Originally Posted by Mewn
I have found the procedure. Just have to find a place where I can judge 2 miles distance accurately.... lol! Highway I guess...
I measured the distance with my DD. I did it locally on a road that was fairly straight. It does not matter if you mainatin a certain speed or even stop. It is counting the pulses that the speedo receives in exactly 2 miles. The key is to get an accurate 2 miles and start and stop your calibration at the exact location. You can be a few feet off. I think mine counted something like 49,000 pulses in the 2 miles. So if yo uare a few pulses off it won't matter to much. I have verified mine with GPS and it is real close. Good luck with it.
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