Powerflex Mk4 - Non
Join Date: Jul 2011
Location: United Kingdom
I think this question was asked and answered in another thread....
The most likely problem is that after removing the OE head-unit the Instrument cluster still thinks its there so is holding the LCD open to receive data from it via the CANBUS.
Try a "Proxy Alignment" procedure with MultiECUScan and see if it comes back. That procedure will tell all the computers connected via the CANBUS to re-detect each other and adjust their settings accordingly.
If that does not fix it then you are going to have to start replacing things.....