Main dipped headlights not working

GJUK said
It appears so, even at the battery, in the boot. with a ground earth and on the 12v + on the battery I get only 5v reading. Take the battery off of the car and it is showing 12v. There must be a ground out live somewhere?

Oh, HELL

If something was drawing enough current to pull the (a good) battery down to 5v, you would have a smoking mess with the fire dept over there

What you have is either a major bad connection at the battery, or a discharged or a defective battery