How are Anti-lock Brake System issues diagnosed?
ABS systems will show the average consumer a code when scanned with a generic code reader, but professional diagnostic software is much more in depth, and is able to access enhanced on-board diagnostic (OBD) trouble codes. With e-OBD codes, the ABS system will generally describe its own failures, but the system has to be tested hands on to determine if the error is due to component failure, circuit failure, or control module failure. In many instances, replacing the part that says it is having trouble will result in a vehicle with a new part and the old fault.
How are Anti-lock Brake System Inspections done?
During the inspection and scan testing, the system may return that it is working properly, as will normally be the case. However, if the ABS light is on, or pending trouble codes are stored, the technician will conduct diagnostics as described, and the faulty component will be replaced. In most cases a wheel speed sensor will be replaced by removing it from the hub assembly and installing the new sensor. However, if the control module or modulator valve has failed, the repair will require removal of at least six brake lines from the modulator valve, disconnecting the battery and control unit, and installing a replacement in reverse order. Finally, the entire brake system will be flushed, filled, and bled to complete the repair. These are just examples, and several other faults can be found when inspecting the ABS system. Repair of the specified fault will vary by make, model, and fault type.
RepairPal Recommendations for Anti-lock Brake System Inspections
In order to maintain the ABS system and prevent untimely failure, we recommend following the manufacturer's specifications for brake system maintenance. Remember that the service brakes are tied into the ABS system, and, for maintenance purposes, these two systems should be considered synonymous. Proper maintenance of the brake system can reduce the risk of contamination of the modulator valve, which is a very costly replacement in most cases.
What to look out for when dealing with Anti-lock Brake System issues
Mixing brake fluid can lead to brake system failure due to congealing of the fluid within the brake lines. The different types of brake fluid, i.e. DOT3, DOT4, or DOT5 are meant for higher and higher braking demand, and will not always result in better braking performance. In fact, except for the most strenuous braking conditions, upgrading brake fluid will likely have no benefit.
Can I inspect my own Anti-Lock Brake System?
Diagnosing the anti lock brake system is not difficult if the proper tools are on hand. Generic code readers inspire confidence for the average user, and may allow the user to diagnose the system properly. However, this is not normally the case, and the codes that will be displayed are general and nearly worthless as there are many duplicate components on the ABS system. A computerized scan tool is usually the best choice, and will allow for much more in-depth analysis and accuracy in diagnosis. If the solution is not obvious, trusting a certified technician can save time, frustration, and cost.
