The ABS and Traction Control Warning Lights on Your Prius

ABS and traction control warning lights appear when your car’s computer detects an
issue, typically signaling a faulty wheel sensor or ABS module failure. Although you
can still drive safely with these warning lights on, hard braking should be avoided in
order to avoid locking up of wheels that could result in an accidental collision.

Brake pads

If your traction control warning light illuminates while driving, seek a safe spot and
stop your engine. This should reset the system and hopefully turn off its warning
light; otherwise it may require professional diagnosis of your issue.

Every wheel on a vehicle contains a speed sensor that monitors how quickly the
wheel is rotating and sends this data directly to the ABS computer. Depending on
the model, certain of these sensors also detect the direction of rotation for each
wheel – this data is essential for various functions on board such as traction control
and antilock braking.

Sensors are constantly exposed to harsh road conditions, and may become
damaged over time. This often results in the traction control warning light coming
on. Sometimes the computer that controls traction control system may become
damaged – in these instances a scan tool will reveal it and the computer should be
replaced accordingly.

Brake fluid

Heavy braking under marginal conditions may lead to wheel lock-up; once this has
happened, logic within the ABS computer detects this and triggers its warning light.

The ABS system utilizes sensors that monitor each wheel’s speed. They resemble
small bicycle sprockets with teeth; each sensor reads its speed individually and
relays that information back to the computer; any damage or contamination of these
sensors could provide inaccurate data and trigger ABS or traction control lights.

Faulty wheels and speed sensors are common on rough road conditions due to dust
and debris exposure, or mechanical wear and tear. An ABS module may also become
defective over time; more often seen on newer cars. With so many moving parts, its
circuitry can wear out over time; using an OBDII scanner that reads ABS codes may
help identify the source of any such failure and provide a solution.

The ABS and Traction Control Warning Lights on Your Prius

Brake rotors

ABS module uses wheel speed sensors to identify whether any wheel is about to lock
up and reduces brake pressure on it, should this happen. If these sensors stop
functioning properly, a warning light will appear and your traction control system
won’t function as expected.

If the ABS light is illuminated, try turning off and restarting your car to refresh its
computer, clearing away whatever transient problem had previously confused its
ABS controller. If that fails, unplug the main harness from its ABS controller before
trying to access wheel speed sensor wires by bridging two pins together with
unprotected wire or paperclip.

Be careful when trying to work around low-voltage signals traveling down these
wires as any resistance could cause them to fail. If this does not help, enlist the
services of a local technician to check the wiring and tone rings for signs of damage;
top mechanics also often have code scanners capable of “talking” directly with ABS
modules in order to figure out what the problem may be.

ABS

ABS systems use a central computer, wheel speed sensors and hydraulic valves in
brakes to monitor each wheel’s speed. A wheel-speed sensor resembles a small
bicycle sprocket with “teeth,” and as the car rotates a magnetic pickup detects when
any of these teeth pass by – giving us insight into its rotational speed as well as
identifying any wheels which might be spinning out or locking up; should this happen
it can reduce some pressure (thus clamping force) on that particular wheel to help it
regain traction and help achieve stability.

Sometimes one or both of your ABS and traction control lights may illuminate for no
obvious reason. If this occurs, find a safe spot to pull over and restart your car; if the
light remains illuminated, seek out a shop with an OBD II scanner capable of reading
ABS codes; this way a technician can inspect for faults in the controller before
replacing any necessary sensors or modules as soon as they’ve been identified.

Leave a Comment

We use cookies in order to give you the best possible experience on our website. By continuing to use this site, you agree to our use of cookies.
Accept
Reject