1998 Olds 88, Replaced all the brake lines (because of corosion) I took care to get lines back on anti-lock unit in same position as origonal. Brake light on dash did go out but the ABS and Traction control light stayed on. Is there a reset? I disconnected battery and ABS fuses to try to reset lights to no effect. Why are my lights on? I havn't had a chance to down load computer.

Have you checked the connectors in the wiring harnesses for the ABS unit and associated components for water intrusion or corrosion?

The codes that you've posted (details below) all point to a poor electrical connection in the circuit(s) or an open or short in the circuit(s). That could be either due to corrosion, liquid intrusion, a wiring harness rubbing against something hot or something that vibrates and has damaged the wiring.

If the wiring and connections are all intact and there are no opens, shorts to power or shorts to ground, the next think to look at would be the modules and/or sensors to make sure they're operating within spec.

U1003 Possible Causes:
*Faulty Anti-lock Brake System (ABS)
*Module Anti-lock Brake System (ABS)
*Module harness is open or shorted Anti-lock Brake System (ABS)
*Module circuit poor electrical connection

The Diagnostic Trouble Code (DTC) sets if the Anti-lock Brake System (ABS) Module fails to receive bus messages from the Dynamic Sensor for approximately 150 ms.

-----

C0020-1c Possible Causes:
*Faulty Anti-Lock Brake System (ABS) *Control Module Faulty Hydraulic Control Unit (HCU)
*Hydraulic Control Unit (HCU) harness is open or shorted Hydraulic Control Unit
*(HCU) circuit poor electrical connection

The Hydraulic Control Unit (HCU) consists of a valve body, pump motor, and inlet/outlets for the brake lines. The combined HCU and Antilock Brake System (ABS) module is located forward of the master cylinder.

The Anti-Lock Brake System (ABS) Module monitors the ABS Pump Motor. The ABS Module sets the OBDII code when the ABS Pump Motor is not to factory specifications.

------

U0125 Possible Causes:
*Faulty Dynamics Sensor Dynamics Sensor
*Harness is open or shorted Dynamics
*Sensor circuit poor electrical connection

The Diagnostic Trouble Code (DTC) sets if the Anti-Lock Brakes System (ABS) Module fails to receive bus messages from the Dynamics Sensor.

Tire, Caliper and bracket, tie rod to spindle, lower strut bolts, remove brake caliper hose from bracket on strut, remove axle nut, Pull spindle away from strut, push axle out of hub, use pry bar and pop axle from Tranny. Make sure when you reinstall axle into tranny your careful not to rip tranny axle seal.Make sure it is fully seated also.

You need a special tool to bleed the brakes because of the anti lock hydraulic control unit trapping air. Any good brake shop and most tire shops have this tool.

on the frame rail under the rear driver side door
be care when change the fuel line broke when I changed mine also the rear brake lines are right there

your power brake booster is blown out
the seal has a leak in it
run the truck for 3 minutes and shut it off. with the windows up listen carefully while you gently apply the brakes
listen for a hissing sound of air leaking.
the sound of these leaking is a very soft sound

no reset button.have the car anti-lock brake system scanned.to check code.because when anti - lock brake light come on.it can be many things.like faulty wheel sensor.faulty relay or the anti - brake unit low on brake fluid or the abs unit faulty.

are you talking about the brake master cylinder, leaking fluid down the fire wall in front of the drivers position? if so ,it is probably running down the inside under the carpet as well.. no matter where its from brake leaks need fixing straight away. it is probably the brake master cyl. that is leaking and it is not a big job to replace it "YOUDOIT"

put the bar on the shoes before you attach the clips and springs.

check your vaccum booster diaphram

I had a similar problem with my anti-lock brake.
One of the will wear down. I took it to the dealer, could not tell why.
Until one day the a brake light came on. It was a bad sensor. Replace the bad sensor and the problem went away.
The mechanic plug a portable instrument and drive the car around until he find out. (The brake light came on, then off.)
This anti-lock brake system is control by sensors and it one is not functioning properly then you have a problem.
I do hope this help you.