Hi,

My 2011 Volvo C30's (85k miles) dual clutch transmission is back at it - It began to shift hard and slow again and this time there's yet another weird diagnostic trouble code. (last time it was broken springs and clips in the clutch assembly)

The code that I'm getting using a dealer level scanner is "TCM-047E" with the description being "Transmission input speed, Plausible Signal". Which is odd, as there are 3 input speed sensors on these gearboxes ("ISS 1", "ISS 2" and "Damper")

After a test drive (Live data recorded and posted as a link to YT), I suspect my damper input speed sensor has gone bad as it doesn't seem to change it's value at all, As far as I remember it should - from what I know it should display the RPM of the engine... does anyone know what it should look like?

The damper speed reading is 0 meaning the sensor is outputting lower than 1.6V /over 4.9V with no square waves (at least it's registered on the TCM) this is odd, usually you'd get readings all over the place that'd get the transmission to go insane... or if the sensor fails it'd usually trigger a check engine light with a clear message (and not some internal module code claiming a "plausible signal")

ANY INFORMATION ON THIS ISSUE WILL BE APPRECIATED

I can get the sensor replaced for $1.5k, BUT at this point I doubt if that's the actual issue - should I shoot the parts cannon and replace more components like the TCM or maybe just spend more and replace the whole transmission? What do you think may be causing all of this? Other sensors seem to be working ok and last tine I had to tear apart the transmission I cleaned the magnet - so I do not think it's metalic dust.

A test drive - accelerating from a standstill.

https://youtube.com/shorts/alXAFL5pIy0

My transmission is the GETRAG 6DCT450 / 6DCT470 - also was installed on the Volvo C30/ S40/ V50/ S60/ V60/ C70/ V70/ S80, Ford C-Max/ S-Max/ Galaxy/ Mondeo/ Kuga, Dodge Journey/ Avenger, Mitsubishi EVO X/ Outlander, Peugoet 4007 and Citroen C-Crosser.

It's often called the "Wet PowerShift" but it has nothing to do with the transmission installed on the petrol Ford Focus ("Dry Powershift" released in 2011/2012), It's closer mechanically to the BMW StepTronic, BMW M-series DCT and the Mercedes 7G-DCT.