I know the text should be in colour as I have gone through the set up before, however all the text is not shown, but the test mode is working as all the tests do work (according to what the LEDs are showing and what is happening on the screen).
As stated the colour RAM test is showing the 8 colours for 2 seconds each when it gets to that test and it is showing the right colours (3 Reds, 3 Greens and 2 Blues) with no bands of colour like the manual says a colour RAM failure would be.
Because of this I know the monitor isn't at fault, and all three colours are shown within the game.
In game, the background is always purple, the aliens are mainly black, the ship is flashing between yellow and blue as is the border around the scanner and scores.
The odd thing is the Defender logo which always has the text in Yellow but the shadow border (which should be red) is always a different colour, I have seen cyan, black, orange, white and yellow.
The game itself works perfectly, with the high score text being white and the high scored being saved fine.