I remember, when I was using the garmin unlocker 1.5 software, I had to create an UNL file in word and I had to save it as All files and name it as an .unl file. This file contained a code generated by the garmin unlocker software, after inserting the unit's ID(Kenwood's) and the used map code(each map has a specific code).
I have picked up a broken 9990HD and I'm trying to repair it.
I have repaired the electrical board, but it still has some issues that prevent it to boot up.
The electrical board(power supply, power amp, tuner), had some traces blown off the board, a trace fuse(fuse made out of the copper layer). repaired these, but it still wouldn't boot up.
Power IC it was overheating, just in case I have replaced it, ut is still a no go.
I have replaced another board in this receiver, which is called the Video Controller Board, from a 6990HD which has a very similar board, with less components on it(lower end unit).
The receiver worked with it. Unfortunately a replacement board is almost $300, so now I'm looking to find a broken unit for parts.
It also has the rebooting issue, which needs a memory chip replacement on the daughter board, to fix that issue. On Ebay there is a seller, that fixes this issue for $129.