ABS Module Help

[CrustyJunker]

On that old of a truck I'd be replacing the brake hoses anyway if they haven't been replaced recently. They'll collapse internally and lock your brakes up, ask me how I know this!

How do you know this?

Good point. I'd heard about this many times...Took me years to actually witness it. Diagnosed as a locked up caliper on a C3500. New caliper, same results! Brake pressure would push the fluid in, then when you let up on the pedal it would collapse the inside of the hose and hold pressure inside the caliper. Not visible just looking at the brake hoses either.

 

[HotWheelsBurban]

How do you know this?

Good point. I'd heard about this many times...Took me years to actually witness it. Diagnosed as a locked up caliper on a C3500. New caliper, same results! Brake pressure would push the fluid in, then when you let up on the pedal it would collapse the inside of the hose and hold pressure inside the caliper. Not visible just looking at the brake hoses either.

2 years ago in September, stopped at an intersection, smells like smoke and I see smoke coming out from under the hood on the right side. Pull over in a parking lot, see actual flames in the wheel well. Left the truck overnight at a shop that was going to "look at it in the morning". Picked it up the next day, $200 later it's allegedly fixed. Heater hose and heater control valve are replaced, had leaked coolant onto exhaust manifold and caused the fire.
Later that day, in bad traffic, starts smoking from the right front wheel well again. Have it towed home. Got it apart, find the melted ABS sensor package. Talked to my mechanic friends and they suggested replacing the calipers, hoses and pads. Luckily the caliper hadn't stuck enough to eat the rotor up.
Long story a little shorter, did all that, replaced that sensor package, replaced the upper ball joints (when apart discovered they were toast)and no more issues. Replaced the pads last month, and the ABS warning light is on now. The main parts house chain here can't scan the computer for codes, so until I can take it to somewhere else to get scanned.....I'm hoping it's the other side sensor since it's original.
Note: allegedly fixed....they put the wrong heater hose on it(a piece of standard hose where it's supposed to be a molded curved 90 degree angle one),the wrong tee fitting, and I am not entirely convinced that the heater control valve was changed either. Was very busy with work and family issues then and didn't have time to argue with them about it. While doing the brakes and ball joints I discovered the hose problem, then found out the tee was wrong when I bought the correct hose. Replaced the hose with one for a Ford because it has the right size on both ends.

 

[Pinger]

Yeah, the brakes should work even if the ABS module doesn't.I think the ABS is like a valve that pulses the brake pressure to prevent wheel lockup in a panic brake application or wet weather.
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There's a pump as well to quickly reapply pressure - if it locks again, pressure dropped, reapplied - rinse repeat.....

How do you know this?

Good point. I'd heard about this many times...Took me years to actually witness it. Diagnosed as a locked up caliper on a C3500. New caliper, same results! Brake pressure would push the fluid in, then when you let up on the pedal it would collapse the inside of the hose and hold pressure inside the caliper. Not visible just looking at the brake hoses either.

My theory is that this is caused by pinching the hose to prevent fluid leak when a caliper or cylinder is removed. Even if I'm wrong, no one will convince me that squashing a steel braided hose is good practice.