2020 Jeep Grand Cherokee Trailhawk, ProCharged 5.7L Hemi
Yes, exactly the same dash lights up, limp home mode, transmission alerts, transfer case alerts... pull over, turn it off, and restart the engine and all is well.When it happens to me I have went above 5,500 RPM's with manual shifting. It is between the 1-2 shift. The engine light comes on, a bell starts to ring and it goes into limp mode. The center of the dash shows something like check 4 wheel drive system or all wheel drive system. Next time it happens I need to take a picture of what the dash says. Happens at the most opportune time and I need to pull to the side of the road, shut it down and restart to disable limp mode in it and keep going. Engine light comes back on until x number of starts or I clear the code with the tuner.
Does yours go into limp mode?
Like you said it is like the transmission has a Rev limit.
The Diabo PMC tune really makes the transmission shift much better with almost instant drop in RPM's.
When uploading an ECU tune it asks if you want to overwrite the factory PMC for the Diabo tune and I do so. It doesn't jump up in rev's between gear changes.
Thanks again for sharing any of your experiences!
In HP Tuners there is a log for 'Throttle Torque Source'. it should read; Pedal, meaning the gas pedal is controlling the engines power. If you reach the Rev-Limiter set by the ECM, it will read 'Rev-Limit', indicating the you reached the engine's rev-limit (and will cut spark and fuel), if you go over that (usually because of momentum, and because the transmissions rev-limiter is set really close to the engines rev-limiter) it will read 'Transmission', indicating that you hit the transmissions rev-limiter. at which time, as in my case, limp home mode, Check Engine Light, dash indicators, etc.
Taking a picture of the dash after is happens won't help, you will have to be data logging to see the cause.
My tune is set up so that I have really good power, throttle and shift response in ECO Mode ON, ECO Mode OFF I have an improved throttle and shift response (Kind of compared to when it was stock, over ECO Mode ON), and Sport mode has even more throttle and shift characteristics (compared to when it was stock, with Sport Mode ON).
From a standing start, in automatic mode, I bounced off of the transmission limiter hard in ECO Mode OFF, I didn't even try it in Sport Mode.
If I didn't want this to happen, mainly because I wanted to use the "Transmission's Tune" (calibration) to shift for me, from a standing start, in manual mode, I would 1>2 shift at 5000, it would complete the shift at 6100-ish, 2>3 at 5500 and it would complete the shift at 6100-ish, and then I would flit the transmission selector in to automatic mode to complete the shift 4, 5, and 6... I am assuming that because in the higher gears, there was less momentum between the gears.
To cure this, as bad as it sounds, we raised the Transmission's rev-limit to 6800 to keep the Jeep off of the transmissions rev-limiter. I haven't had it happen since, in any drive mode.
... sorry, I get a little long winded at times.