Yesterday our MK1 Octy developed a strange fault with the indicators everytime you use them the brake lights flash with the indicators also we have noticed that this fault only happens when you press the brake pedal so if we used the indicators they are fine until you touch the brakes then they go off and then the brake lights flash.

Its the same with the hazzard lights when we put them on the brake lights including the high level one flash on and off, its bizzare.

I was looking for some pointers on what to check as its a bit dangerous, thanks everyone.

Check the connections in the rear light unit, especially the earths, and the earting points (brown wire) that will probably be in the boot somehere. Look at the light units first, that's most likely. What is happening is there's a dodgy earth, and it's finding a path back via another lamp, so they all start to interfere with one another.

Just confirming what cjb says above - this fault is invariably a bad earth.

Thanks guys it was the brown earth wire the spade connector in the boot had snapped and was green so i have cleaned the area and soldered another conector on to the wire and its fine.

Thanks again.