ReadyNAS Duo RND2000 V2 - LEDs Blinking don't know what to do

Greetings,

I have an issue with my ReadyNAS DUO RND2000v2

When I turn it on the fan startsup full rev and will not turn down.
The appliance will start blinking the following code.
power and ACT will flash 3 times followed by the disk LED blink 5 times.

I've had this problem for quite a while and I'm unable to find documentation on the blinking lights, that corrosponds with this particular type of ready NAS.

I suspect that the firmware is corrupt so I tried to do an USB restore.
I followed the instructions on the support page,

1. I downloaded, extracted and wrote the latest raidiator firmware to an USB thumbdrive using rawwrite.
2. I powered down the nas
3. inserted the the thumbdrive in the front USB port.
4. powered up the NAS holding the powerbutton until the the disk led blinked for the fourth time. (not sure if I did that properly as it didnt take +- 20 seconds)

I'm at a loss, so that's the reason for my post here in the forum.

Looking forward to the replies.

Kind regards.