The brake warning light in my 1990 Pajero LWB auto stays on in the morning after I start up and drive off. It's not the handbrake because if I leave the handbrake off overnight, the light is still on when starting up in the morning. I took the sensor wire off the brake booster, and earthed it but that makes no difference. When I take the low level sensor connection off the master cylinder the light goes out, and comes on again when I connect it up again. The master cylinder is full of fluid.
During stop start driving during the day the warning light goes off, but sometimes comes on again if I brake.

Any Ideas anyone? I've checked the booster in the normal way and it seems fine. Braking seems normal as well. <img src="/forums/images/graemlins/confused.gif" alt="" />