TRying to understand the system- abs/brake lights on

[we287gn]

Hey all...I have been poking around in the search ..Tons of posts on bleeding procedures and abs problems and I am still confused as to what exactly my problem is.... I am guessing before I replace anything else I need to understand what my Rear only abs system consists of.. I am also guessing the unit itself consists of the solenoid and a system pressure sensor??? Here are the symptoms.. 1.brake and ABS lights on... 2. could be wrong here, but I pissed through a set of rotors(rear drums on my truck) in less than a year..I had been pulling some heavy trailers and assumed I needed a rear brake job and that possibly I was overworking the fronts... 3. In the meantime, I had replaced a locking driver caliper and went through the front lines after I found some leaks... The first job(caliper) after we blead the brakes the lights were out, but as soon as I stepped on the pedal, the ABS and brake light would come on.. TIme had passed and I discovered a leaky front brake hose.. I thought for sure this is why we previously seemed to have lights coming on.. After the brake hose change the lights have stayed on.. I have had a $100 actron scanner on the truck a couple of times reading ignitions problems, never popped up any brake codes(not sure that it would) so all of this mess has happened over a years time, I have such a short comute, I can get away with nursing the truck back and forth to work.. But its time to nip this thing in the bud .. Pushing 200K I decided to change a coupl emore suspect lines and throw in a rebiult master cylinder.. I thought I had it for sure, even though the previous pedal was decent , this felt better ..But no change in the light situation... I have come to an opinion that its possible my problem lies in the rear system.. It seems to me that it feels like my back brakesks are hardly working at all..this adds to my train of thought on the previously mentioned year old rotors... Now being that I have read the ABS solenoid is normally open, I am thinking bleeding should be no differrent.. But now the only things that havnt been replaced are the rear axle hose, the pressure valve(guessing this is in place of a prop valve ) and the ABS sol itself I have read about bleeding the at the solenoid, but this rear only unit doesnt have a bleeder? I appollogise for the jumbled up post...I hope it makes sense..I am a bit urked and its late, just trying to get all the info out there in case anyone would like to try and help me understand the system and possibly finally troubleshoot the actual problem.. I am used to the older set up, dual piston mc, prop valve(with pressure switch in it), then off to rotors and drums. On my truck I am assuming the proportioning valve setup is kinda replaced by th e"pressure valve" and the kind of prssure at the valve is dictated by weather or not you have all wheel disc or just fronts..And I assume the pressure switch is in the abs sol... Witch leaves me one last question ....The thing-ama-bob in the resevoir must be a low level sensor???? Thanks to anyone who had the patience to read through this !!! Chris Pacheco

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[we287gn]

Still reading up and searching..
Came across a post about checking the ABS codes..

Went to take a peak at the truck to check on my E brake switch..Then it hit me..
I never hooked the E brake cable onto the frame..Now I do not have enough slack to hook it back on..
Is it possible I need to let out the brake adjustment to get the cable back on..?
If that is true I am also wondering that if by not having the cable tension in place , did that throw off the position of all my break hardware possibly letting my wheel cylinders come out way to far?
In other words even with the tension on the drums set to have some drag, that maybe the cylinder pistons are on max travel...???? I then tried to bleed the system with the wheel cylinders almost on max..Nothing left to move???
HAve to wait till later to jack it up and get the cable back on and test this theory..

EDIT: while I am sitting here thinking about this, before I get that far...That theory needs to get tossed out the window..If that were true(brake adjustment dependant on E brake cable tension), the brakes would fail if the e brake cable failed...oh well, trying here...
All this making me think back to when I swapped the new cables and wheel cylinders on(back when I did a rear end swap)...I am starting to wonder if I got the wrong wheel cylinders now????The housings looked the same and they bolted right in...hmmmm????
I need to confirm this , maybe I can snap a pic of the wheel cylinders...I sorta remember questioning the posistion of the wheel cylinder "extension " in referance to the completely closed set of shoes..
I thought to my self that the cylinder looked close to being on full stroke..

I will feel silly if its something stupid like this, but happy if I can finally get a good brake system going here...

Thanks

[we287gn]

Not sure if t was the bleed between the valve and rear cylinders, or the fact that i dropped a used vlave/abs sol in the truck.
BAsicly went as far as changing all rear lines and hose..Still bad pressure.

So last resort was to swap in the $15 dollar used boneyard vlave..Without even re-bleeding the rear cylinders,(just bleed the line coming out of the valve) the lights went out and back breaks were working again..

Pulled drums let out adjusters, hooked up parking break cable, re-adjusted rear breaks....Everything is back to normal , lights out , breaks and E -break working as they should.....