Nissan Repair: nissian quest brake, internal seals, haynes manual

Question
QUESTION: I changed the front brake pads and had the rotors turned, then added brake fluid and now the brake light is on and I don't know what to do?  going on vacation is 2 days and wife is concerned.  Thanks for the help  Mickey

ANSWER: Mickey,

THe brake pressure switch is used to show if there is a difference in the pressure from the front to the rear.  If there is the light will trip.  When you did the front brakes you had to compress the pistons and when you were done the pistons had to come back out when you pressed it a couple of times.  So, this is what turned the light on.  Bleed the brakes and the light should turn off.  That means you need to bleed the rear first and then the front.  Get a Haynes Manual and follow the directions within and you should be fine.

---------- FOLLOW-UP ----------

QUESTION: Thanks for your fast response.  I bled the rear brakes then the front.  Made sure fluid was full but light is still on.  Also when the engine is off I have good firm pedal but once I turn the engine on, pedal goes to the floor.  Any suggestion.  Thanks again   Mickey   P.S.  Nissian service man told me there was a censor on the master cellanor and that could be stuck.  What do you think?

Answer
Mickey,

If the pedal is going to the floor when the vehicle is running you have either air in the system that still needs to be bled or the master cylinder itself has blown internal seals and that is causing the light to come on.  If your quest has something like 100K miles on it I would replace the master cylinder.