25989531 | Genuine GM® AntiLock Brake Module For Silverado 1500 - 2009-2014

An Anti-Lock Brake Module (ABS module) 25989531 is the electronic control unit that manages the anti-lock braking system in a vehicle. It works together with wheel speed sensors and hydraulic valves to prevent the wheels from locking up during hard braking.

General Specifications

Fitment

Fitment can vary by engine build and options. Match the part number on the part you are replacing, or contact us with your vehicle details before ordering.

Purpose & Function

1. Monitors wheel speed

Wheel speed sensors send signals to the module many times per second.

2. Detects wheel lock-up

If one or more wheels slow down too quickly (about to skid), the module identifies that as lock-up.

3. Controls brake pressure

The module rapidly pulses the brake pressure through hydraulic valves:

• Reduces pressure to a wheel starting to lock

• Reapplies pressure when traction returns

This action happens many times per second—much faster and more precisely than a human could pump the brakes.

4. Helps maintain vehicle control

By preventing wheel skid, the ABS module allows:

• Straighter stopping

• Steering control during hard braking

• Better stability on wet or slippery surfaces

Signs of a Bad AntiLock Brake Module

1. ABS Warning Light On

• The ABS light on the dashboard is the most common sign.
• Sometimes the Traction Control or Stability Control light also turns on because those systems rely on the ABS module.

2. Brakes Lock Up Under Hard Braking

• If the module fails, the ABS system may not activate.
• The wheels can lock up, causing skidding or loss of steering during emergency stops.

3. Unresponsive or Weak ABS Operation

On slippery surfaces, you may notice:

• No ABS pulsation in the brake pedal

• The ABS doesn’t “kick in” like it should

4. Increased Stopping Distance

Without proper ABS control, the vehicle can take longer to stop, especially on wet or icy roads.

5. Brake Pedal Feels Abnormal

A failing module or its hydraulic control unit can cause:

• Pulsating even when not braking hard

• A soft/spongy pedal

• A hard, unresponsive pedal (less common)

6. Speedometer Problems (in some cars)

Some vehicles rely on the ABS module for speed data. If the module fails, the speedometer may stop working or behave erratically.

7. Traction Control or Stability Control Failure

Systems like ESC, TCS, and VSC use the ABS module.
If the module goes bad, you may see:

• “TRAC OFF”

• “ESC OFF”

• “Stability Control Disabled”

8. Wheel Speed Sensor Codes (Even If Sensors Are Good)

A failing ABS module may misread wheel sensor signals, causing false sensor trouble codes.

About GM

General Motors (GM) is one of the largest and most iconic automotive manufacturers in the world. Founded in 1908 and headquartered in Detroit, Michigan, GM designs, builds, and sells vehicles under several well-known brands, including Chevrolet, GMC, Cadillac, and Buick.
GM is known for its long history of innovation in the automotive industry, from developing early electric vehicles to advancing autonomous driving and connected car technologies. The company has a strong global presence and is committed to a future of zero crashes, zero emissions, and zero congestion, with significant investments in electric vehicles (EVs) and sustainable mobility.