Your Toyota Corolla’s anti-lock braking system is an integral safety measure, helping
prevent your tires from locking up during heavy braking and risking loss of control
over the vehicle.
If both ABS and brake lights illuminate simultaneously, there may be an
issue with your ABS system and it should not be driven until it has been resolved.
Low Tire Pressure
Whenever the ABS light illuminates, you should immediately pull over to a safe
location and inspect your tires. A tire pressure monitoring system is designed to
detect low air pressure levels and alert drivers of potential danger. If any one or
multiple of your tires appear low on air pressure, increase them up to the
recommended values set forth on the driver’s door panel of your car.
Extremely low tire pressure can reduce the diameter of your tires, leading them to
spin faster than other wheels and potentially setting off an ABS fault code on that
wheel. Additionally, this could set off warning lights for both traction control and
stability control systems.
Resetting the sensor by disconnecting and reconnecting the battery may help if this
is indeed the problem, however if it still persists you will need to conduct further
investigation including checking for blown fuses or relays, among other possibilities.
Many OBD scanners will display codes related to what caused this light, which may
help narrow down what may be causing this light to illuminate.
Damaged Wheel Speed Sensor
If one of your wheel speed sensors breaks, it could prevent your ABS system from
operating correctly and disable both traction control and stability controls in your
Corolla, forcing you to use only standard brakes during driving; antilock brakes won’t
be available anymore.
Damaged sensors will cause the computer in your car to send inaccurate information
to its ABS controller, so you should periodically use a multimeter to test them and
observe their resistance values; an ideal sensor should have between 800 and 2000
ohms as resistance reading.
Replace a wheel speed sensor if you have access to a garage and possess basic
mechanical knowledge. Gather necessary materials such as jacks and stands to
safely raise your vehicle, a wrench set, ratchet/socket set and safety glasses before
disconnecting the battery cable and draining all remaining power from the system
by repeatedly pressing the horn button or switching on headlights for 15 minutes to
drain power out of system.
Low Brake Fluid Level
If the BRAKE or ABS light illuminates, this indicates a problem with your anti-lock
brake system. This safety feature prevents your wheels from locking under heavy
braking, making it easier to keep control of the vehicle and avoid collision.
The ABS system works using both electronic and mechanical parts. The electronic
part monitors wheel speed sensors for signs of lock-up. If one fails, this signals the
hydraulic control unit to pulse the brakes at that particular wheel to reduce pressure
levels on that specific one.
It can also happen when the master cylinder reservoir’s fluid levels drop too low,
prompting you to check whether either of your fuse for ABS module or relay is blown
or defective – then, replace or repair as appropriate and resetting the ABS light
accordingly.
Blown Fuse or Relay
If both ABS and Brake lights illuminate, that indicates an issue with your braking
system that requires in-garage diagnostics or a visit to your dealer for repair.
Fuse boxes work much like circuit breakers; they use wire rated for specific amps
(Amps) to protect the circuit and in the event that its load exceeds this capacity,
they will cut off, necessitating replacement with another fuse to reinstate your
circuit’s power supply. If overload occurs, however, then its fuse will blow and you
must replace it in order to reactivate your circuit again.
Your Corolla features sensors on each wheel that monitor how fast they’re spinning,
sending this information directly to the ABS controller. Should one of these sensors
malfunction and deliver inaccurate speed readings, the ABS light in your dashboard
may illuminate in response.
If the problem cannot be remedied by lowering tire pressure, checking fuse/relay
voltage levels, or changing brake fluid, your only recourse may be to reset the ABS
system with an OBDII scanner. Doing this will also clear error codes from your ABS
controller which may help identify what the source of your issue might be.