2006 Sierra ABS issue - Locking up no codes

[double a ron]

Hello all, first post, searched but haven't found anything online or in this forum for my particular issue.

 

Truck is new to me, 2006 Sierra Denali AWD.  I had it out yesterday in some snow and ice for the first time, all 4 brakes are locking up and rear end wants to come around, ABS not even attempting to work, no sound, pedal feel, or modulation on any surface.  However I have no ABS lights, no codes, and fuse is good.  Fluid level is good, no obvious issues noted.

 

Any thoughts?  Attached a pic to show her off.....

[davester]

I would suggest cleaning the grounds bolted to the wing on the frame under the driver's side door, then use a code reader that can get abs codes to read them.

 

And perhaps also look at the brake lines running along the frame rail from the front wheel to the abs controller (as well as the brake line going to the rear, along the frame rail above the fuel tank if you have an inspection camera), as they are known to rust through, and then you are in for a very interesting time...

 

Edit: reread your post saying it has no codes.  did you use a code reader that could get them from the abs system?

Edited October 19, 2020 by davester

[redvett]

A code reader will only read powertrain codes a scanner (Tech 2) or equivalent will read all the vehicle modules, body, ABS, SDM etc. I suggest you get a scanner to integrate your vehicle.

[double a ron]

I will clean that ground, lines are all good, and get a better scanner.  Thanks guys.