Service Transmission and Limp Mode with 6MT

[J Sunsurf]

So, I’ve been struggling with this issue all summer. Intermittent service transmission light, vehicle in limp mode whenever I drive on the beach (isn’t there a Desert Rated badge on the side?)

Put in an ACT clutch at the dealer when I found one who would do it (some dealers refuse to install aftermarket clutches). That gave me the confidence that the clutch won’t catch fire.

Back at the beach last week. Every 1/4 mile or so, it goes into limp mode. This time I ran some video showing that I was specifically not touching the clutch at all. Definitely a software problem.

I’m giving up. I’m going to take it in the requisite amount of times and ask for a buyback. @Birds83, didn’t you find an aftermarket guy that will reflash your PCM to pre-recall programming? That would be my other option, but I think I’m just tired of Jeep ignoring this issue. My specific use case is beach driving, and Jeep is unable to address that in a $50,000 truck. I don’t like to constantly hassle Jeep, but their refusal to address this issue is negligent customer service.

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[Birds83]

So, I’ve been struggling with this issue all summer. Intermittent service transmission light, vehicle in limp mode whenever I drive on the beach (isn’t there a Desert Rated badge on the side?)

Put in an ACT clutch at the dealer when I found one who would do it (some dealers refuse to install aftermarket clutches). That gave me the confidence that the clutch won’t catch fire.

Back at the beach last week. Every 1/4 mile or so, it goes into limp mode. This time I ran some video showing that I was specifically not touching the clutch at all. Definitely a software problem.

I’m giving up. I’m going to take it in the requisite amount of times and ask for a buyback. @Birds83, didn’t you find an aftermarket guy that will reflash your PCM to pre-recall programming? That would be my other option, but I think I’m just tired of Jeep ignoring this issue. My specific use case is beach driving, and Jeep is unable to address that in a $50,000 truck. I don’t like to constantly hassle Jeep, but their refusal to address this issue is negligent customer service.

I did it’s called hemifast and was recommended by Zautomotive. I never looked into it but I think 1 person I heard had and was successful. Not sure on year of that Jeep though.

I fixed my transmission isssue permanently.

1997 f250 powerstroke with 5 speed
Sitting on “35’s”

 

[Stan H]

Seems to me , I aint no expert , and I know you have a 6MT , But could ypur problem be related to traction control ?

 

[J Sunsurf]

I did it’s called hemifast and was recommended by Zautomotive. I never looked into it but I think 1 person I heard had and was successful. Not sure on year of that Jeep though.

I fixed my transmission isssue permanently.

1997 f250 powerstroke with 5 speed
Sitting on “35’s”

Well, you’re not getting stuck in that! Nice rig.

 

[J Sunsurf]

Stan, thanks for the reply. Birds and I have been dealing with this for almost a year now. Synopsis is, everyone believes that the algorithm used by the powertrain control module to determine clutch temperature simply doesn’t work in sand. The algorithm was put in place to alleviate the exploding clutch recall.

None of the dealers, nor has STAR been able to solve the problem, nor does the traction control system have any complimentary errors (according to STAR). It simply says the clutch is slipping too many times, thus it’s too hot, thus the system is working to prevent clutch overheat. Not once has Jeep offered to drive it, test it on sand, or frankly do anything other than offer me money after it was in four times. I took some money and put in the ACT clutch, which is awesome and bulletproof. But it still throws the error. I’m assuming Jeep would rather throw money at buying back a few vehicles than do the research to correct their own program. It’s a shame. I’ve been a Jeep guy my whole life and this will probably do it for me. I’m going to see what’s going on in a Bronco MT.

Nobody at Jeep is listening. It’s really no wonder they are having issues. For what they charge for a new vehicle, I would expect them to fix the so called “desert rated” trucks before there’s a class action suit.

 

[Stan H]

Stan, thanks for the reply. Birds and I have been dealing with this for almost a year now. Synopsis is, everyone believes that the algorithm used by the powertrain control module to determine clutch temperature simply doesn’t work in sand. The algorithm was put in place to alleviate the exploding clutch recall.

None of the dealers, nor has STAR been able to solve the problem, nor does the traction control system have any complimentary errors (according to STAR). It simply says the clutch is slipping too many times, thus it’s too hot, thus the system is working to prevent clutch overheat. Not once has Jeep offered to drive it, test it on sand, or frankly do anything other than offer me money after it was in four times. I took some money and put in the ACT clutch, which is awesome and bulletproof. But it still throws the error. I’m assuming Jeep would rather throw money at buying back a few vehicles than do the research to correct their own program. It’s a shame. I’ve been a Jeep guy my whole life and this will probably do it for me. I’m going to see what’s going on in a Bronco MT.

Nobody at Jeep is listening. It’s really no wonder they are having issues. For what they charge for a new vehicle, I would expect them to fix the so called “desert rated” trucks before there’s a class action suit.

Okay , here I go again, can the previous flash be removed back to original. ?
2nd question does it also throw this code in soft mud??
3rd question : Does it do it in low range with the lockers engaged ???
4th question : What type of rear-end do you have ? Limited slip, Full spider ?
I know you said it is a Mojave .. which means at least the rear locker is available.
5th Question does it do it without the rear locker engaged?
6th Question: have you considered installation of a front locker from say Eaton .
Thanks.

 

[Birds83]

Okay , here I go again, can the previous flash be removed back to original. ?
2nd question does it also throw this code in soft mud??
3rd question : Does it do it in low range with the lockers engaged ???
4th question : What type of rear-end do you have ? Limited slip, Full spider ?
I know you said it is a Mojave .. which means at least the rear locker is available.
5th Question does it do it without the rear locker engaged?
6th Question: have you considered installation of a front locker from say Eaton .
Thanks.

Mine (2023 Mojave)did it on road or off road in 4Hi or low and traction control off.
Doesn’t matter if it’s stock or modified….. some times I could go 1,000 miles sometimes 5. Never could nail down anything that would set the light on particular driving style/conditions that would set it…. Delt with the issue for 10,000miles.
Sets no codes and only way to reset the service transmission light is to reset the clutch eeprom to reset the slip counter.
Jeep won’t revert to pre recall software aftermarket is the only option….

 

[Bbannongmu]

This sux. I haven’t seen any issues in my 2020 M/T Rubi at 50k miles with a CF Clutch …in sand numerous times, in mud, in rocks…. I had the first clutch / computer recall done. I’m never going back to a dealer unless I absolutely have to.

 

[Stan H]

Mine (2023 Mojave)did it on road or off road in 4Hi or low and traction control off.
Doesn’t matter if it’s stock or modified….. some times I could go 1,000 miles sometimes 5. Never could nail down anything that would set the light on particular driving style/conditions that would set it…. Delt with the issue for 10,000miles.
Sets no codes and only way to reset the service transmission light is to reset the clutch eeprom to reset the slip counter.
Jeep won’t revert to pre recall software aftermarket is the only option….

I winder if an aftermarket solution could be attained to fool the clutch eeprom .. much like what is done in diesel deletes to the oxygen sensors?? What is the trigger to all this its that sensor eliminates the sensor by trickery and you may have your answer. Does it have a pressure switch it runs off of etc.. possibly run it to different area to where it never senses any changes... just rambling.. on the diesel deletes the oxygen sensors are fooled with a few diodes and wiring harness left in place.

 

[Birds83]

I winder if an aftermarket solution could be attained to fool the clutch eeprom .. much like what is done in diesel deletes to the oxygen sensors?? What is the trigger to all this its that sensor eliminates the sensor by trickery and you may have your answer. Does it have a pressure switch it runs off of etc.. possibly run it to different area to where it never senses any changes... just rambling.. on the diesel deletes the oxygen sensors are fooled with a few diodes and wiring harness left in place.

My understanding is that it uses the input and output speeds sensors and I think if it doesn’t see what it expects then “the clutch is slipping” and after enough occurrences the light comes on.

 

[KQL]

I think I’ve seen some posts of people reducing or eliminating limp mode activation by messing with tire sizes in the computer. It seems that by changing the tire size, you change what the computer is considering acceptable range of wheel speeds before it decides that slippage is occurring. It’d definitely consider making that adjustment in the computer.

 

[J Sunsurf]

KQL, thanks for that reply. I have tried measuring the actual tire sizes when I air down and resetting the tire size. I should probably experiment with larger / smaller than actual. My little brain can't figure out which way is more beneficial lol. The problem is when it happens, I'm on vacation and just want to keep going. But that's a great thought.

Birds, I reached out to the tuners. They're on Long Island, a couple hours away from me. I'll probably wait until after the holidays, but I'm going to talk to them about doing the pre-recall flash. My concern is that one year in and 12,000 miles, I don't want to impact my warranty.

 

[Birds83]

KQL, thanks for that reply. I have tried measuring the actual tire sizes when I air down and resetting the tire size. I should probably experiment with larger / smaller than actual. My little brain can't figure out which way is more beneficial lol. The problem is when it happens, I'm on vacation and just want to keep going. But that's a great thought.

Birds, I reached out to the tuners. They're on Long Island, a couple hours away from me. I'll probably wait until after the holidays, but I'm going to talk to them about doing the pre-recall flash. My concern is that one year in and 12,000 miles, I don't want to impact my warranty.

I wasn’t gonna reflash till after warrenty ran out but well you see how that went…

as far as tire size in computer larger or smaller. I tried this and found if I made the tire size smaller it seemed to prolong the time in between the light setting some bit of course your speedo and odometer are off some.

 

[7BJT]

I am taking my Jeep to the dealership for the second time, so they can reset limp mode again. This time I was towing a 4500lb overlanding trailer up an incline at 5000 feet in the mountains when I lost all power. Safety issue much Chrysler? That same Jeep towed that same trailer across the country last year with zero issues... pre software "fix" (virus) install. Is anyone aware of a software fix for this issue yet? It sure seems that the official discontinuance of manual transmission production was the final break-up letter with our shotty Stellantis relationship. "You're on your own now, good luck, thanks for your purchase!"

I have contacted AJ with Hemifast in New York... that is the only "fix" I am currently aware of...

Fun fact: also had a new engine put in at 25,000 freaking miles.

 

[J Sunsurf]

AJ with Hemifast is your best bet. In the meanwhile, use Jscan or a Tazer. I have jscan because they had the limp mode reset feature before tazer came up with theirs. Either one works, you can pull over and reset.

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