Your profile states that you have a 2001 Wrangler (TJ) Sahara. The programmer you purchased is designed for 1998-2014 jeeps and will not calibrate your speedometer.
There are two methods for calibrating your speedometer:
1. Change the speedometer gear in the transfer case as illustrated in the link provided by Chris in Post #3 [
https://wranglertjforum.com/threads...our-speedometer-after-changing-tire-sizes.83/]; or
2. Use an electronic correction device such as the Yellow Box
https://yellr.com/yb_home.htm or SpeedoHealer
.http://www.bluemonkeymotorsports.com/products_ht.html.
The first method works with the NP231 transfer case, which is the transfer case you most likely have, and is well documented in the link,. It should cost about $35.
The second method is the only method that will work with the NP241OR transfer case in the '03-'06 TJ/LJ Rubicon, but will also work with the NP231 transfer case. The current price for the Yellow Box is about $110; the price for the plug-n-play SpeedoHealer is $160.
Unless you miscalculate the number of teeth you need for the new speedometer gear to calibrate your speedometer with your current gear ratio and tire size, you should only need to purchase one gear per gear change or tire size change. In other words, you should be able to change gears or tires about 4 times before the electronic speedometer correction device becomes less expensive for your particular application.
However, if convenience is more important to you than the lowest cost alternative, or if you change between winter and summer tires each year or plan to go with larger tires in the future or a different gear ratio, then you should consider the SpeedoHealer.
I considered both the Yellow Box and the SpeedoHealer when I calibrated the speedometer in my '06 LJ Rubicon last year and decided, all things considered, that the SpeeoHealer was the better buy even though it cost a few dollars more. I do not regret my purchase. Installation took less than 15 minutes from start to finish and did not require any wiring or disassembly of any parts. Programming took less than a minute after a 10 mile test run with a GPS unit to measure the actual speedometer error. Best of all, when I re-geared from 4.88 to 5.38 all it took to re-calibrate my speedometer for my new gear ratio was another test run and a few seconds adjusting the percentage of correction. One can store two settings for situations such as changing between winter/summer or street/trail tires. BTW, customer service for the SpeedoHealer is excellent.
Hope this helps.
