Virtually all automotive systems that are electrical in nature run their power through some sort of system of fuses or relays and the ABS is no exception. Because fuses are essentially a bridge for power in electrical circuits, when they fail they can cause all sorts of problems for their respective systems and should be replaced. Fuses are usually installed into smaller individual circuits with low current draw, while relays are more commonly used for higher amperage circuits.
When they fail, they can cause all sorts of problems for the system that they were providing power for. Specifically, when the fuses and relays of the ABS system fail, usually the vehicle will display a few symptoms that can alert the driver that there may be a problem with an ABS fuse or relay.
1. Illuminated ABS Light
One of the first symptoms of a blown fuse or relay is an illuminated ABS Light. The ABS Light will become illuminated once the computer has detected that there is a problem with the system. If a fuse blows, or a relay fails, the computer will pick up the signal and activate the Check Engine Light to alert the driver that a problem has occurred. An ABS Light can occur for a wide variety of reasons, so if it does come on, have the vehicle scanned for codes to help shed some light on what the problem may be.
2. Tires are locking up regularly
Another symptom of a possible problem with a fuse or relay is a malfunctioning ABS system. More specifically, a failed relay may cause the ABS symptom to act up. If the relay is unable to adequately supply the ABS system’s electrical needs, it may cause the system to malfunction. In some cases, the ABS system may even activate at random times, sometimes even while the vehicle is in motion.
3. Blown fuse
One of the most obvious symptoms of a fuse or relay problem is a blown fuse. Fuses are designed to handle a specified amount of amperage, and are designed in a way that if the set amount is exceeded, the fuse will literally blow to protect the circuit. Close inspection of a blown fuse should reveal a dark and perhaps cloudy appearance on the inside of the fuse. The wire inside of the fuse should also be visibly split when the fuse is blown. A blown fuse will usually deactivate the entire system, or at the very least the circuit that it was responsible for powering.
Because the anti-Lock fuse and relays are what power the entire ABS system, they are very important electrical components to any vehicle. For this reason, if you suspect that your ABS fuse or relay may have failed, have a professional technician, such as one from YourMechanic, diagnose the electrical system to determine if the car needs the anti-lock fuse or relay replaced.
This article originally appeared on YourMechanic.com as Symptoms of a Bad or Failing Anti-Lock Fuse Or Relay and was authored by Ed Ruelas.