Symptoms of a Bad or Failing ABS Fluid Level Sensor

The ABS system is an additional safety feature that is now mandatory on all late model vehicles. The ABS system uses electronic sensors to detect wheel speed conditions and rapidly pulse the brakes to prevent the tires from skidding, and can rapidly stop the vehicle. The ABS system uses an electrical control module, and a series of sensors, one of which is the ABS fluid level sensor.

The ABS fluid level sensor is responsible for detecting the amount of brake fluid present in the vehicle’s brake master cylinder reservoir. This is important for the module to know because the entire braking system, as well as the ABS system operates using hydraulic brake fluid, and will not function correctly if the level falls below a certain minimum. When the ABS sensor fails, it will usually display a few symptoms that can alert the driver that there may be a problem that should be serviced.

1. The ABS Light is on

One of the first things that may happen when the ABS sensor fails is the ABS Light will come on. The ABS Light will usually come on when it is detected by the computer that the sensor has failed or is sending an incorrect signal, which may cause the ABS system to have problems. The ABS Light can also come on for a variety of other reasons so if it does become illuminated, scan the vehicle for trouble codes to reveal clues as to what the possible problem may be.

2. Unexpected wheel lock

Another symptom of a problem with the ABS fluid level sensor is a malfunctioning ABS system. Usually, the ABS system will activate automatically during heavy braking situations where wheel lock occurs. However, if the ABS fluid level sensor fails, and the level falls below a certain point, then the ABS system may not do this. This may leave the vehicle prone to unexpected wheel lock and tire skidding if the system is not functioning correctly.

3. Low fluid in reservoir

Another symptom of a failed ABS fluid level sensor is a low fluid level. This is usually indicative of two problems. One, that the fluid has somehow escaped from the system, perhaps through a leak or evaporation; and two, that the fluid level dropped and it was not picked up by the sensor. Usually, if the fluid level is low and the light has not come on, then the sensor is defective and should be replaced.

Because the ABS fluid level sensor is important to the overall functionality of the ABS system, if it fails, the problem can quickly transfer over to the rest of the system. If you suspect that your ABS fluid level sensor has failed, or your ABS Light has come on, have the vehicle diagnosed by a professional technician, such as one from YourMechanic, to determine if the vehicle needs an ABS fluid level sensor replacement, or perhaps another issue that needs to be addressed.


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Jesse

17 years of experience
127 reviews
Jesse
17 years of experience
Jaguar S-Type V8-4.2L - Brake System Inspection - Palm Coast, Florida
Jesse showed up for the appointment timely and ready to work. He was polite and professional and competent. He took sufficient time to inspect the vehicle and explained in layman's terms any problems and whatever corrective work that might be required. I highly recommend Jesse and hope to have him service my vehicles again in the future if needed.
Ford Escape - Brake System Inspection - Daytona Beach, Florida
Jesse arrived on time after sending notice 15 mins prior. A true professional Jesse got right down to business. He started his inspection work right away and did a thorough professional job and determined the solution to his findings. I am very pleased. He is a true expert mechanic.

Johnny

34 years of experience
392 reviews
Johnny
34 years of experience
Toyota RAV4 L4-2.4L - Brake System Inspection - Sacramento, California
Johnny arrived early which was great, he performed the inspection in less than half an hour, and gave us a complete quote for all items needing attention, including the brakes as our main concern. Johnny is fast and efficient so I scheduled the work done by him.
Ford Escape - Brake System Inspection - Sacramento, California
The convenience is worth the cost. I was also tired of the dealership not really caring about my old car. Last couple of times I had to wait well over an hour to get my car after the dealership said "It's ready!". They also wouldn't fix the things I asked saying they didn't have time and I need to come back.

Luis

30 years of experience
119 reviews
Luis
30 years of experience
Honda Accord V6-3.0L - Brake System Inspection - Northbrook, Illinois
He's excellent. On Time, honest and all repairs done quickly and correctly. Book him if he's available!

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16 years of experience
246 reviews
Christopher
16 years of experience
Nissan Sentra L4-2.0L - Brake System Inspection - Charlotte, North Carolina
Very informative and made sure to clarify on what he spoke on so that I understood what was happening with my car

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