Clutch Recall (FCA W12 | 20V-124) on 2018-2020 JL Manuals [overheating clutch pressure plate]

cnapierala

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This solution did sound a little “fishy” until someone figured out the manual transmission has a gear indicator. Since that’s available it should be a simple calculation to detect clutch slippage as described above.

I’m not worried about this fix (now) and will get it done. I’d rather not have the gear indicator on the dash, but I’ll learn to live with it.
Maybe JScan can develop a way to turn it off? I'm not sure I'm excited about it either but plan to get the fix done either way.
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Toycrusher

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This solution did sound a little “fishy” until someone figured out the manual transmission has a gear indicator. Since that’s available it should be a simple calculation to detect clutch slippage as described above.

I’m not worried about this fix (now) and will get it done. I’d rather not have the gear indicator on the dash, but I’ll learn to live with it.
It DOES NOT have a gear indicator. It does have a clutch on/off switch on the master cylinder and a clutch position sensor on the pedal inside. Transmission itself has no sensors whatsoever.
 

COBill

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It’s not fishy, it’s physics. And they aren’t calculating temp, they’re calculating unexpected slipping (which results in heat). Think about it. If you’re in 4th gear going 45 mph and RPM spikes to 4500, you have a problem.
It would have to be done in conjunction with the traction control system as wheel spin could also account for the situation you describe.
 

Toycrusher

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It would have to be done in conjunction with the traction control system as wheel spin could also account for the situation you describe.
There are individual wheel speed sensors in each wheel and an output speed sensor in the transfer case. What it could calculate is a change in engine rpm with no change in clutch pedal position and no change in wheel speed. That would indicate something wrong and be used to trigger power reduction.
 

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AlamedaJeep

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AnnDee4444

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FWIW: I've used software to tune another manual vehicle, which also knew the transmission's gear ratios and differential ratios. It was able to tell what gear I was in in real-time using nothing but the speed of the vehicle vs RPM... no extra gear selector sensor in the transmission was used.
 

COBill

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I guess the obvious way to check would be to idle, push in the clutch and see if the dash display changes as you move the gearshift to different positions.
 

SargeRubicon14

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I guess the obvious way to check would be to idle, push in the clutch and see if the dash display changes as you move the gearshift to different positions.
While sitting at idle with the clutch depressed, the dash display does correctly display all the gears as you shift through them. It also display N if you leave it in the middle.
 

Jebiruph

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Very interesting. Well, my 2018 definitely does not have anything electrical in it, just had it down this past weekend. Curious what year that diagram is from.
The post with the wiring diagrams is dated 11/30/2018. Maybe they're reading the shifter position.
 

kgrencer

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Curious how well this flash would play with those of us that have gear swaps changing from factory ratio, and relationship of driveline speed to wheel speed..... Not the first time a vehicle of mine would be bricked in an FCA service bay
 

EMS

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Curious how well this flash would play with those of us that have gear swaps changing from factory ratio, and relationship of driveline speed to wheel speed..... Not the first time a vehicle of mine would be bricked in an FCA service bay
It will be interesting to see how the new FW acts when users re-marry their Tazers. I'll never know, my JL will never darken the door of an FCA service bay again.
 
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