I noticed yesterday that the brake lights weren't working on my MGB (oops). Here's the thing though, both bulbs are ok; when I bypass the switch (by connecting the plugs on either side of the switch together) both brake lights come on so all wiring is ok too. So, it's the switch isn't it... but the thing is, when I connect a test meter up to the switch I get 11.8volts out of it when the brake pedal is pressed. Now this admittedly is a bit less than the 12.1volts I get from the live feed going into the switch but surely this is enough to make the bulbs light up?
What could be going on here?
Before someone says replace the switch anyway?can this be done without bleeding the brakes and the suchlike afterwards as it screws straight into a four-way junction of brake pipes?
Thanks in advance.