Hey guys,
Alright, my bosses son has a 92 honda accord, it had disc all around. he came in with a low pedal, the brake fluid is not low, and the pedal was hard and at the right location when the car is off, but when you start the car, the pedal drops to the floor. I bleed the system and that did not help. so of course this sounds like text book bad master cylinder, so i replaced it,bench bleed it, and bleed the system. same problem. all the brake pads and rotors are new, we replaced the front calipers because the left front was returning poorly. and still the pedal drops to the floor.
So now like every tech out there i was thinking, it is possible that the master i got was bad, i mean it happens. so i got another one and bleed it, the works. but still the pedal drops to the floor.
Now the only thing i can think of is the abs modulator, it has an abs light on, but my boss said it has been on for year (goes with the old joke that the mechanics car is allway broken lol) i dont have the tools to bleed the abs, so i am kind of stuck now.
oh and just to say, i am a tech, but i specialize in GM cars and trucks, so i am in new territories now, not use to the honda systems.
What do you guys think? 
idk the code my boss said that he looked up the code a long time ago, but never fixed it. idk why if it was me i would fix anything wrong with the car i drive.
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