Morris Minor Owners Club

just come back from the MOT station when I was told the car had failed on one item, the brake lights did not work, they were checked when I took it down as I was pulling out of the garge forecourt my wife flashed me to and said they worked as I stopped, I walked back to the tester and told him but his comment was they did not work on the rolling road so it was a failure he said the brake light switch needed adjusting I showed him they were working and after a heated disscussion I got a new MOT ticket. by the time we got home my wife said they came on occasionally depending how hard I braked ,so obviously the switch needs adjusting.

but I cannot find any reference to it any of my workshop manuals anyone give me a clue?

The switch is not adjustable, it works on the brake fluid pressure(on the
engine compartment floor to the left of the radiator). to test it I would short
the two wires on it together (Green and green/purple) with the ignition on this
should operate the stop lights reliably. if this is so then the switch is suspect.
If not then, assuming that you still have the early relay unit fitted in the engine bay you could have a problem in this area. Do not leave the ignition
on without the engine running for long.

Willie wrote:The switch is not adjustable, it works on the brake fluid pressure(on the
engine compartment floor to the left of the radiator)..

The RIGHT (off side) as seen from the driver's seat, to clarify.

CORRECTION, since your model had/has semaphore indicators you obviously
do not have the Relay in the engine compartment so test the switch and,if
you need to replace it remove it carefully as the whole assembly can twist
out of the floor if it is not in good condition.

Certainly sounds like a switch fault, only closing under higher pressure.

It's screwed into the tee piece right at the front of the engine bay, where the pipe from the master cylinder splits to go to the left and right wheels. I think on your age Mog, it will be the same as mine, and have screw terminals. The later ones had lucar (spade) terminals. You can use the later ones but you'll have to crimp terminals on your wiring harness.

The screw terminal ones fit too, and I've found them a lot more electrically reliable. ESM (and everywhere else, I expect) do them.

thanks for the replies , if this proves unsuccesful then I might change to a ford brake light switch, fitted onto the brake pedal behind the dash on a spring and this is adjustable , will mean altering the wiring though