I'm still looking for your exact model number, I found some DE models but can't find the DE27C, it's very strange to replacing the control that has the readout incorporated into the control that you can't see it, I have been looking at the service technical sheets on the dryer and there is a diagnostic mode in these, I fear however the control board that was installed is faulty, but try this,
5.3 Diagnostic Mode
5.3.1 Entering the Diagnostic Mode
(a) Turn the power supply to the dryer on.
(b) Press and hold the Auto Dry down button, then press the Power button.
The dryer is now in level 0 of the diagnostic mode. After initial entry into the diagnostic mode, the
Start/Pause button operates the dryer as normal. Press the Auto Dry up or down buttons to scroll
through the fault levels.
There are several levels of diagnostics, most of which are used in development and production. These
levels may bring on various LEDs, but the level of use for the service technician is that of the last fault.
18.104.22.168 Last Fault
To enter the last fault diagnostics, enter the diagnostic mode as described above, then press the Auto
Dry up button three times. The last fault will be displayed on the drying progress LEDs as described in
See if this even goes into the diagnostic mode, let me know thanks, Bryan