Return tv from test mode?

Hi

I have a DMTECH LW19XTM LCD TV which appears to be in TEST MODE...

When switched on the whole screen Starts Black.
After 1 second the whole screen is filled with 4 horizontal stripes of solid Red, Blue, Green and White (in descending order).
After another second the whole screen is grey.
After the next second the whole screen is White.
The screen then goes black for 1 second and the cycle repeats.

It is no longer under warranty and DMTECH Service Centre will not help.

Can you help?

Regards
Will