2015 Tranny Limp Mode - No Codes

[RHalle]

The last two times I've towed my travel trailer I've had tranny issues without any kind of check engine light or trouble codes. This has happened three times now and only when towing. It generally occurs while steadily climbing a hill at 65-75 MPH and when the tranny downshifts from 4th to 3rd it will immediately bounce back into 4th and stay that way (limp mode) until stopping and re-starting. No check engine lights or stored codes (using Autoenginuity scan tool). The most recent time this happened I pulled over and it shifted to 1st (without having to re-start). I thought maybe it had self cleared and so I started moving and it immediately jumped to 4th so I stopped, re-started and it cleared it from limp mode.

Most of Limp mode conditions I've read online seem to be from tranny solenoids but all of the threads I've read have an associated trouble code.

Any thoughts?

Also anyone know if the 2015 has a separate Transmission Control Module or if it is combined with the Enhanced Powertrain? Using the AE Scan tool I do see some tranny sensors in the enhanced powertrain section but I was expecting a TCM also.

2015 PW
70K miles

Thanks,
Ryan

[KevinABQ]

I assume no issues with trans temp?

[RHalle]

Temp was normal. In all three cases temp was between 172-174 degrees.

I’m wondering if others have had the check engine light come on after limp mode or just stored codes indicating solenoid issues?

Thanks,
Ryan

[RHalle]

I’m also noticing that downshift from 6->5 is generally pretty rough/abrupt (general highway driving conditions without towing). Whether I roll onto the gas at freeway speed or force a downshift using column buttons. Not sure if this could be related to the limp mode issue.

I’m still surprised there have not been any codes thrown.

-Ryan