So I know when I change the gear ratio in the axles I will have to tell the jeep what the new gear ratio is. Once I connect the jscan to the jeep and do what I have to do can it be used on other jeeps or is it only good on my jeep.
How to use a JScan tool
- Thread starter SteveF
- Start date
I don't know if that function is available in "Demo" mode or not. Normally, you'd purchase the license to your VIN and the JScan will then recognize your Jeep each time you plug it in.
I would think, although I could be wrong, that if you simply leave it in Demo mode, every time you plug it into your JK you'll have to enter everything you've done to your JK, otherwise no information it gives you will be accurate.
I would think, although I could be wrong, that if you simply leave it in Demo mode, every time you plug it into your JK you'll have to enter everything you've done to your JK, otherwise no information it gives you will be accurate.
IndominusHuman
JK Enthusiast
You will buy a license and that one will work for your jeep vin only, but you can buy additional licenses as well.
When you open the app, you will see a gear icon on the top right. Click that and go to Manage Licenses & Account. From there you can buy a license or add one.
The demo feature is just to play with and see what they have. You will need to purchase the license to really do anything.
When you open the app, you will see a gear icon on the top right. Click that and go to Manage Licenses & Account. From there you can buy a license or add one.
The demo feature is just to play with and see what they have. You will need to purchase the license to really do anything.
chuckdaviscreative
Member
It's super easy to use, thats for sure. Fixed my speedo and Daytime driving lights. Had to use my fogs for that. I have halos on my front signals that I wanted to use but, there's no provision to use running lights as DRL. The license is just a little over $20. Well worth it. I'll have it to activate a backup cam when I install that with the factory stereo later this year.
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So where do I get one and is that what I need to tell the Jeep what the new gear ratio is?
chuckdaviscreative
Member
Jscan is a free download from the App Store or the Android equivalent. You need a OBD2 dongle to make it work. That's about $100. There's a section on the app with recommended dongles. I'm using the "OBD Link MX+"
https://www.amazon.com/dp/B071H5W7H7/?tag=jkforum-20
$32 and works perfectly! I've had it for a good while now.
T
$32 and works perfectly! I've had it for a good while now.
T
I need one because I am re-gearing my axles and need to tell the jeep of the new gear ratio and tire size
When I do an app search for OBD2 it come up with several apps. What do you all recommend. This is all so new to me I appreciate everybody's advice
xackley
JK Enthusiast
Jscan is the app that can change settings.
This 14$ obd2 reader works fine.
https://www.amazon.com/gp/product/B011NSX27A/?tag=jkforum-20
I used these to turn on DRL and to lower tire pressure warning down to 20 lb.
Jscan will also let you view more systems than most apps.
type jscan in google to find their web page.
Don
edit: don't change things just because you can. There is no magic reset button, you have to know what you changed and change the settings back one at a time.
This 14$ obd2 reader works fine.
https://www.amazon.com/gp/product/B011NSX27A/?tag=jkforum-20
I used these to turn on DRL and to lower tire pressure warning down to 20 lb.
Jscan will also let you view more systems than most apps.
type jscan in google to find their web page.
Don
edit: don't change things just because you can. There is no magic reset button, you have to know what you changed and change the settings back one at a time.
FLCoastJK
Member
That Jscan and dongle worked like a charm for me. Pretty cheap truthfully for what you get.
I don't plan on changing anything but the gear ratio setting when I have my axles re-geared. I was told that if I don't it will go into the limp mode and won't go past 2nd gear.
chuckdaviscreative
Member
Looking at the Jscan demo, if you go to "adaptations" and "Tire Size & Axle Settings" and "Axle Ratio" it will allow you to change ratio. Tire setting is a little further down the menu. You can take a real measurement of your actual tire height, enter that into the app and your speedo will be correct. Worked perfectly here. I didn't have to change ratio. I've got a
Rubicon. 4:10 is already set.
Rubicon. 4:10 is already set.
I just ordered the Icar pro from Amazon. The ODB Link M+ will not work for JK's. That what it says on the list of supported OBD's
Twisted289
Member
That is correct. I changed my gears to 4:10 and the trans went into limp mode. As soon as I reprogrammed it was all good. I bought A Flashpaq. It was pricey but I changed tire size and gear size. I can program all kinds of stuff with it.
The transmissions shift points will be off and your speedometer will be way off if you don't recalibrate it. Has to be done if it's a tire or gear change.
chuckdaviscreative
Member
This is the one I was referring to. The screen shot is from Jscan. Works fine with my '17 JK.