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JScan 850re quick learn

croppz

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Are we supposed to do the long or short quick learn on this? When I select short it says “may not be supported on this module” but will let you continue until you get to the gear shift movement and then once you press proceed it says “negative response from ECU”. Are we supposed to do a long quick learn instead?

Using an OBDlink MX+ and a security dongle.

Jeep Wrangler JL JScan 850re quick learn IMG_6150
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bmpcamry09

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Transmission learn function is technically only supposed to be used after a transmission repair to reset adaptives like you’re doing a valve body repair or the like. Otherwise, there’s really no need to do it.
 
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croppz

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Transmission learn function is technically only supposed to be used after a transmission repair to reset adaptives like you’re doing a valve body repair or the like. Otherwise, there’s really no need to do it.
Understood. Just trying to reset the previous owners driving habits that it learned over 50k miles. I’m weird like that I guess lol.
 

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Understood. Just trying to reset the previous owners driving habits that it learned over 50k miles. I’m weird like that I guess lol.
The whole “habits” thing is a complete myth and blown out of proportion on forums. The only thing the transmission “learns” and saves for true long term measurement is what pressures/times/apply rates that are required in order for the transmission to complete the shift process in the time/rate that the TCM is expecting to manage heat, slip, and proper shifting. Shift schedules remain unchanged.

By resetting adaptives, your transmission has to learn its condition essentially. Has nothing to do with driving habits, just bad info that has been thrown around forums for years.
 
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croppz

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Well tha
The whole “habits” thing is a complete myth and blown out of proportion on forums. The only thing the transmission “learns” is what pressures/times/apply rates that are required in order for the transmission to complete the shift process in the time/rate that the TCM is expecting to manage heat, slip, and proper shifting. Shift schedules remain unchanged.

by resetting adaptive, your transmission has to learn its condition essentially. Has nothing to do with driving habits, just bad info that has been thrown around forums for years.
Okay cool that’s great to know, especially coming from someone that messes with these regularly. Appreciate the help and insight my friend!
 

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No problem! Yeah this whole “learn” thing has been talked about for years by people who’ve never been inside one.

These DO “learn” your aggression behavior when driving. There is a timer within the transmission that can change what shift schedule tables are used based on your driving behavior. BUT, the timer for that resets to 0 as you drive, and it defaults to base shift scheduling every restart and doesn’t have a long term learn factor.

Hopefully more people read this thread and see this, because thats how it truly works. This topic has always been a pet peeve of mine 🤣
 
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croppz

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No problem! Yeah this whole “learn” thing has been talked about for years by people who’ve never been inside one.

These DO “learn” your aggression behavior when driving. There is a timer within the transmission that can change what shift schedule tables are used based on your driving behavior. BUT, the timer for that resets to 0 as you drive, and it defaults to base shift scheduling every restart and doesn’t have a long term learn factor.

Hopefully more people read this thread and see this, because thats how it truly works. This topic has always been a pet peeve of mine 🤣
It’s exactly why I posted it. Could hardly find any information on the subject except “it learns your behavior just reset it!” Lmao! The more proper info out there, the better.
 

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There is alot more going on in there than i realized, Bmpcamry whats your opinion on fluid change interval, or never changing like Jeep claims.
 

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There is alot more going on in there than i realized, Bmpcamry whats your opinion on fluid change interval, or never changing like Jeep claims.
I am a 30,000 mile kind of guy. I do transmission, transfer case, and diffs all at the same 30,000 mile interval. Replace original fluid and filter/pan at 30,000. Then do just fluid every 30,000 from that point maybe doing the filter every other time after that.

Over the years I’ve grown to really like Valvoline Maxlife in these units too versus the factory fluid. But that’s a whole other discussion lol under warranty I’d stick with the factory fluid.
 

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I have been considering getting new pan and having drain plug welded on before first fluid change. Anyone tried that, those that have changed fluid before do you think its worth it.
 

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bmpcamry09

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I have been considering getting new pan and having drain plug welded on before first fluid change. Anyone tried that, those that have changed fluid before do you think its worth it.
I don’t think it’s worth the hassle. The pan comes off in a few seconds. I can do a complete pan off service on these in under 30 minutes. No exhaust to fight with like on Ram trucks. Everything is wide open.
 

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No problem! Yeah this whole “learn” thing has been talked about for years by people who’ve never been inside one.

These DO “learn” your aggression behavior when driving. There is a timer within the transmission that can change what shift schedule tables are used based on your driving behavior. BUT, the timer for that resets to 0 as you drive, and it defaults to base shift scheduling every restart and doesn’t have a long term learn factor.

Hopefully more people read this thread and see this, because thats how it truly works. This topic has always been a pet peeve of mine 🤣
Genuinely asking here, not trying to be argumentative. When i bumped up to 35's and changed the tire size in JScan, my trans would almost never shift out of 6th gear, even steady state throttle, downhill, at 70 mph. I drove it like that for about a week to see if it would correct itself and it never did. I reset the adaptations with JScan and now it behaves like I would expect it to on 35's and stock gears. Steady state, flat ground, 70 mph I'm in 7th. Downhill in 8th. What would cause that to work?
 

bmpcamry09

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Genuinely asking here, not trying to be argumentative. When i bumped up to 35's and changed the tire size in JScan, my trans would almost never shift out of 6th gear, even steady state throttle, downhill, at 70 mph. I drove it like that for about a week to see if it would correct itself and it never did. I reset the adaptations with JScan and now it behaves like I would expect it to on 35's and stock gears. Steady state, flat ground, 70 mph I'm in 7th. Downhill in 8th. What would cause that to work?
It makes sense because resetting adaptives probably forced a module alignment between the PCM and other modules, in your case I do recommend adaptive reset because the heavier load with bigger tires could change the way the transmission slip timers and everything behave.
 

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It makes sense because resetting adaptives probably forced a module alignment between the PCM and other modules, in your case I do recommend adaptive reset because the heavier load with bigger tires could change the way the transmission slip timers and everything behave.
Ok, so basically the extra load is making the TCM think there's different wear in the trans than there actually is?
 

bmpcamry09

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Ok, so basically the extra load is making the TCM think there's different wear in the trans than there actually is?
That is definitely a possibility, the TCM on these itself on these as far as actual shift scheduling does not care what your tire size is, shifting is completely reliant on drive shaft/output shaft speed. However, the extra load generated by the heavier tire and the extra throttle input needed to make them do the same work can make your aggression counter go up and hold the gears like you experienced before.
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