Service Brake Warning Light On!

[cajunjohn]

Help, please, guys!! Driving through the Smokies, the yellow "service brake" light came on on the dash board of our '99 36 FDS. After an overnight it was off, but just a few miles and it is on again. Not sure if it requires immediate attention or can wait one to two weeks for us to get home. I called my home RV mechanic and he said probably not serious because it is illuminated yellow not red. Braking seems unaffected. Any opinions?

[ga traveler]

The first thing to do is check your brake fluid level. Some chassis are wired to come on with low brake fluid.

[bigfish]

May be just a anti-lock sensor on one of the wheels, if so, not serious, may only need a slight adjustment.
BTF
05 40FDQS

[Algoma]

I am assuming that the light comes on when you turn the ignition switch on and goes off once the engine starts. Then at some point on the trip it comes back on. Did it come on by itself or when you applied the brakes? The Alpine does not have a fluid level sensor and if it was an ABS detector issue the ABS light would come on, not the "service brake" light. There is a pressure switch in the master cylinder which turns that light on if there is a difference in pressure between the 2 sides of the braking system, i.e. you have a leak. If the fluid levels are OK and the brakes are working it may be that the switch is playing up.

[EngineerMike]

If its been years since brake fluid service, then its time for that anyway. I'd do a full brake fluid change if it was my rig.