Yellowbox Speedometer Correction Install (1 Viewer)

[Eyedaho]

So... Has anyone tried the Dakota Digital SGI-100BT for their speedometer correction project?
SGI-100BT: Universal Speedometer and Tachometer Interface

Dakota Digital Accessories

You’ve purchased Bluetooth-enabled Dakota Digital accessories and want to get the most out them, all with wireless control? The Dakota Digital Accessories App allows you to do just that! When using the SGI-100BT --------------------------- -Speedometer and/or Tachometer input and output...

apps.apple.com

This looks to be a far more advanced unit than the Yellow Box that most folks use and allows calibration adjustment with onboard pushbuttons like the Yellow Box, but also with an IOS (iPhone) or Android device via Bluetooth. Meaning one can install the module behind or under the dash and recalibrate at will without need to actually get to it. It also seems very reasonably priced at around $94 on Amazon...

So I've ordered one of these and will install it in the next week here. In preparation to install it I've studied the signals from the speed sensor and confirmed couple things I've not found documented elsewhere here on IH8Mud... Hopefully others will find it useful.

1. The number of pulses per mile (PPM) from my '97 80 series LC - For this I put the truck up on jack stands and ran the truck for two miles as indicated on the odometer trip meter and recorded a total of 8198 pulses for an average of about 4100 pulses per mile as measured with a Universal Counter.
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2. The nature of the signal into the speedometer as viewed with an oscilloscope - A very clean square wave 11.5V signal with a period of approximately 60mS at an indicated speedometer speed of about 15mph.
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3. For purposes of connecting the unit I'll be cutting the red-orange wire on pin-1 of the IH1 connector behind the glove box to insert the Dakota Digital speed calibrator. (the problem will come in determining which side of the wire goes to the sensor and which goes to the speedo... )
   
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Female pins go to the sensor and male to the speedo according to your ewd picture, right?

 

[Bud_Dude]

Female pins go to the sensor and male to the speedo according to your ewd picture, right?

I hadn't noticed that... Thank you for the observation, it would seem logical and agrees with the nomenclature description in the manual.

PS - I'll be further documenting this installation in the following thread - Bud's '97 80 series speedometer correction project

 

[Bud_Dude]

OK - Job done and the answer is yes the Dakota Digital unit works well at correcting the speedo and works on cruise control
Check out the install details here - Bud's '97 80 series speedometer correction project

 

[gregnash]

Nicely done!!! So for someone that has limited electrical knowledge/prowess is this something that you would rate as a difficult job or ??? Contemplating doing this down the road to add for tire size correction as I will like always run 33s on my truck.