No brakes on my 2001 Yukon Denali

[melaniec1225]

My husband has replaced all the brake lines on our 2001 yukon Denali and bled the brakes numerous times. When the car us off it feels like we have brakes but when we turn the engine on the pedal still goes to the floor. Help

 

[pwtr02ss]

I would guess that you have air in the ABS module. You need to have a scan tool that is capable of actuating the module while bleeding the line

 

[Scottydoggs]

i agree with the air but it might be in the master, if at any point the master ran dry. best way to bleed the master on the truck is to pump the brakes like a you would to bleed a caliper, pump hold, then crack the hard line nut off the master, if theres air you'll hear it spitting out, repeat till just fluid comes out on both lines.

i like to break the line nuts free first, then snug em back up, now put your wrench back on and wrap a rag around the nut and wrench to keep from making a mess.

after you bleed the master you'll need to re bleed all 4 calipers. making sure the master does not run dry doing this, or we're back at step one again.