"ABS" and "Brake" lights come on same time

My S10 is doing an "odd" thing, and has for some time. The "Brake" and "ABS" lights come on simultaneously after driving a short distance. I'm beginning to think this is a fairly common problem with GM. When the truck is stopped and restarted, the lights go off, but after a little while they come back on. My wife's Regal does the same thing, only the "service engine soon" light comes on in addition to the "ABS" and "Trac On" lights. Any help would be appreciated.

The S-10 (depending upon what model year it is) may be simply the brake fluid level sensor reporting low fluid level. This can happen from inertial forces and brake usage once the vehicle is moving. Make sure the brake fluid level is maintained at the "MAX" fill line to avoid this. If the level appears correct, there may be a problem with the level sensor, level sensor wiring, or some other ABS problem.

The Delco ABS-VI system is fairly sophisticated, yet elegantly simple in terms of it's need for input sensors. Wheel sensor problems are usually detected on startup or as soon as the vehicle is rolling at about 5-7 MPH. Pressure modulator motor and solenoid problems are usually detected on startup. As long as the speedometer is working, we can presume (for now) that the vehicle speed sensor is reporting correctly, so that would leave that possibility out. About the only things left are the ABS power supply relay, brake pedal switches (both service brake and PARK brake), brake lights (some of which are monitored by the system), and brake fluid level switch.

The Regal may use a different ABS system, and would therefore have different characteristics and diagnostics. I'd suggest you post a thread in the J-Body or Regal forums, and include the model year. By your brief description of the warning indicators, I'd suspect a problem with a wheel speed sensor or its circuit.

My S10 is doing an "odd" thing, and has for some time. The "Brake" and "ABS" lights come on simultaneously after driving a short distance. I'm beginning to think this is a fairly common problem with GM. When the truck is stopped and restarted, the lights go off, but after a little while they come back on. My wife's Regal does the same thing, only the "service engine soon" light comes on in addition to the "ABS" and "Trac On" lights. Any help would be appreciated.

Wheel speed sensor probably have a bad reluctor. When vehicle begins to move the reluctor rotates there is a little mpu in the case that counts the notches on the reluctor to tell the abs computer how fast the wheels are turning the light pops on when the vehicle begins to move. It usually takes about 30 feet that sucks when you are pulling the customers car out that you thought you fixed and the light comes on.:runaround: