TPMS and J-Scan

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Zombie

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Need guidance. I run 30 psi in my tires and used jscan to try and eliminate my warning light. Changed my low threshold form 28 to 24 and my placard psi from 35 to 30 but I’m still getting a warning light.

Also i changed my tire diameter in abs to correct my speedo but its still off my the same amount. Any help would be appreciated
 
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Welcome to the forum! I turned mine off years ago so I can't remember what settings in Jscan but I think there are basic and EVIC. You have to do both. For the tires, you have to use they physical size of the tires. Just say your running 35's. A 35 might only measure 34.25" or 34". Tire size needs changed in tire axel settings. Make sure you stay in Jscan while the update is refreshing. If you swap between apps while you wait, it might not save your information to your Jeep. I hope this helps.
 
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I can't remember how I fixed my TPMS either but it seems I only went thru one step and it was done. I only get the notification when I air down to off road.

On setting your speedo - the sidewall for like a 315/70/17 that I run actually mathematically come out to a 34.36". Under load if I put a level on top of the tire and measure it's an inch or so shorter. Been a long time and I can't remember how much shorter. To get my speedo to match the GPS on my dash cam which matches those radar signs on the side of the road I had to use down to like a 32.25" as my tire size. Maybe one up or even one down from that, I can't remember.

The gist is no matter what "size" tires you buy, they are shorter than the sidewall says, even shorter under weight and you have to input them even shorter into JScan to get the speedo right.
 
I used a GPS to set mine when I did a tire change to make sure it was set according to the correct speed.

I don't have JScan yet and used my Hypertech to set it.
 
JeepJeezy said:
Welcome to the forum! I turned mine off years ago so I can't remember what settings in Jscan but I think there are basic and EVIC. You have to do both. For the tires, you have to use they physical size of the tires. Just say your running 35's. A 35 might only measure 34.25" or 34". Tire size needs changed in tire axel settings. Make sure you stay in Jscan while the update is refreshing. If you swap between apps while you wait, it might not save your information to your Jeep. I hope this helps.
Click to expand...

The tire diameter is in mm. I went from 2460 to 2760 and it made no change to my speedo. As far as my TPMs I only have the base version my dash does no display for psi. When I open the app it shows my ecu took all these changes but it’s like the ecu isn’t using the new parameters
 
DickensCPA said:
I can't remember how I fixed my TPMS either but it seems I only went thru one step and it was done. I only get the notification when I air down to off road.

On setting your speedo - the sidewall for like a 315/70/17 that I run actually mathematically come out to a 34.36". Under load if I put a level on top of the tire and measure it's an inch or so shorter. Been a long time and I can't remember how much shorter. To get my speedo to match the GPS on my dash cam which matches those radar signs on the side of the road I had to use down to like a 32.25" as my tire size. Maybe one up or even one down from that, I can't remember.

The gist is no matter what "size" tires you buy, they are shorter than the sidewall says, even shorter under weight and you have to input them even shorter into JScan to get the speedo right.
Click to expand...

Mine is in mm and circumference. I went from 2240 to 2740 and no change to my speedo
 
Make bold adjustments. You want to go too far. Then dial back till it’s right. Kind of like the old school way of adjusting a carburetor……
 
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Zombie said:
The tire diameter is in mm. I went from 2460 to 2760 and it made no change to my speedo. As far as my TPMs I only have the base version my dash does no display for psi. When I open the app it shows my ecu took all these changes but it’s like the ecu isn’t using the new parameters
Click to expand...

Same here, when I went from stock to 33s it made no change to my speedo either. I BARELY made a change going from 33s to 35s.
 
Greetings,

I have a 2010 JK (2-door) Rubicon and I've been using the Android version of OBD JScan for a couple of years. Using it I've successfully done the following:
  • Configured my fog lights as Daytime Running Lights (DRL).
  • Lowered the TPMS warning threshold to 27 psi.
  • Deactivated the Flash Lamps On Lock, Horn Chirp Allowed, Sound Horn On Lock features.
  • Activated the rear window defroster and wiper after installing a Mopar hardtop upgrade kit (a huge and very complex job!!!).
  • Bled the anti-lock brake controller after a full brake upgrade (which included a Mopar military master cylinder and booster).
The first time that I attempted to adjust the TPMS warning threshold, it did not work. I had to do what JeepJeezy said. Even though my 2010 JK Rubi has only the "basic" TPMS and TPMS Premium is shown as "Deactivated", yet I had to set both the TPMS Threshold Basic and the TPMS Threshold EVIC warning light settings to 27 psi. To ascertain if the change has been made, exit JScan, remove your OBD interface, wait a minute, then reconnect your interface and launch and pair JScan to your Jeep. Then return to the TPMS Threshold settings and check to see if the "current value read from ECU" of both the Basic and EVIC settings equals the value you want. If it does, the change has been accepted and is operational.

Regarding Tire Size, the "current value read from ECU" by JScan lists three parameters: Tire height (mm), Tire circumference (mm) and Tire height (inches). The JScan note says to "READ HELP BEFORE CONTINUE". I have never needed to change my tire height setting (it was alreadly set correctly), but I will need to change it in the future. It sounds like you need to go to the JScan website and read their "help" information to do this successfully.

Regarding the anti-lock brake controller bleed, the procedure only has you bleed the front passenger and rear passenger wheels. It never asks you to bleed the driver side. This is correct. According to a FAQ on the JScan website—all air is bled from the controller through the passenger wheels. (Of course, the JScan procedure assumes that you have done a full conventional brake bleed of all four wheels before you bleed the anti-lock brake controller.) It can be difficult to get all the air out of the anti-lock controller, so some mechanics recommend doing the procedure multiple times. In my experience, I found that doing the anti-lock brake bleed procedure three times in a row, is usually sufficient. Another note: During the procedure the anti-lock brake controller will activate multiple times to push air out. Wait until after the first activation to open the bleed valve so the line will be at full pressure.

Question: Can OBD JScan be used to pair new TPMS sensors to my Jeep? If "yes", do I use the WCM - TPMS Tire Sensors Idenfication setting to initiate the process? I'm planning on upgrading my wheels and tires and, when I do, I'll purchase new TPMS sensors at the same time. Do I need a dedicated TPMS scanner to pair the new sensors to my Jeep or can JScan do the job?

Regarding the OBD JScan app, it is filled with incorrect spelling, incomplete descriptions and unnecessary redundancy (some settings are listed in more than one place). If these are evidence of the quality of the programming, this is not a very good app. The only reason I use it is because I'm unfamiliar with any other. If someone can recommend an affordable alternative that is better, please do.

Kind regards, FirstLight
 
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JScan is a great app. Unless you find access to dealer only scan tooling, you won’t find a better tool.

The TPMS sensors should not need to be programmed. At least when I replaced mine on my 2016 they connected automatically. I assume your 2010 is the same but I do not know that for a fact.
 
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Thanks, Mopar.

Here's a bit of TPMS trivia that others with a 2010 JK or JKU may want to know: 2010 was a transition year for the Wrangler. Jeep was already planning for the 2011 model, with its new interior and new electronics. Previous JK/JKU models (2007-2009) communicated with the tire pressure sensors at 315 MHz. But 2011 and all later years switched to 433 MHz. Jeep anticipated the launch of the new 433-MHz sensors in 2010 and began to make the switch during that model year. Early 2010 models still had the 315-MHZ sensors. Later 2010 models had the 433-MHz sensors. So Jeep gave all 2010 models a TPMS receiver that works with both frequencies. Therefore, if you need to replace your tire pressure sensors in a 2010, you can use either the 315-MHz model or the 433-MHz model. Both should work fine. This affected my family when we purchased our 2010 JK Rubi a couple of years ago. We didn't like the tires on it and the dealer offered to swap wheels from a 2008 model that had the tires we wanted. He explained the above so we would know that we could use the 2008 tire pressure sensors in the 2008 wheels with the 2010 Jeep with zero problems.

My wife and I have been using Wranglers as daily drivers and adventure platforms for decades. We started with a 1978 CJ-5. Then a 1993 YJ Sahara. Then a 1997 TJ Sahara (the only Jeep that we purchased new—we special-ordered it from the factory in order to get anti-lock brakes which were first introduced that year, but were still optional). We had our TJ for 27 years until the frame had rusted so bad that it could no longer be repaired. Our next Jeep was our most difficult decision. We wanted another new one but the prices were insane. And new Wranglers were unfriendly for DIY repairs and had a bad reputation for CAN bus problems (like locking you inside or outside of your "dead" Jeep when an error refused to cycle out). A number of owners had this happen when they stopped at a red traffic light and found themselves trapped inside a "dead" Jeep. Crazy! So we tried to determine what was the latest model we could purchase that included the recent improvements, yet was early enough to avoid the electronic problems and still be user-repairable. 2010 seemed like the best year. It still had the 3.8L EGH engine which is easy to repair and fairly cheap to replace. It included the most important JK upgrades (especially the Rubicon) without the new electronics that began in 2011. We live in Michigan (hence the rust problem) but purchased our Rubi from Nevada so it came virtually rust free. We made sure that it did not have power windows, electric door locks or pushbutton start (so a CAN bus problem could not lock us in or out or disable the ignition switch). And we have the undercarriage treated anually at Krown in Holland, Michigan, for rust protection. So far, the frame and undecarriage still look like new. We love our 2010 JK Rubi. It is, by far, the best Jeep for us. We are already planning our next purchase: we want to add a 2010 JKU to our stable.

Kind regards, FirstLight
 
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For what it’s worth, the 3.6 engine JKs aren’t hard to work on at all. JScan makes it even easier. Personally, I’d avoid the 2012 and 2013 models but 2014-2018 I’d buy without issue.
 
FirstLight said:
Don't you have to remove a manifold on the 3.6L Pentastar to change three of the spark plugs?
Click to expand...

Yes….the upper intake manifold….but it’s easy. Probably takes 15-20 mins once you are familiar with it. Maybe 30-45 mins your first time.

Removing an intake manifold to replace one side of spark plugs isn’t unique to Jeep. You’ll find that in many other makes and models too.
 
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I'd say the 3.6 is more tedious to work on, not necessarily harder. I've helped my friend with his plenty.
 
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