Identifying the symptoms of brake valve failure is critical to maintaining your vehicle’s braking performance. Combination proportional valves play a crucial role in regulating brake pressure between front and rear brakes. If they fail, they can lead to rear wheel locking, uneven braking and excessive forward dives when braking. Before you can identify a fault, you need to understand how it works.

How the brake proportioning valve works

A brake proportional valve is a valve that manages how the braking force gets to all four wheels by changing the pressure of the brake fluid. In simple terms, combination brake proportioning valves automatically change the pressure of the brake fluid depending on the load and resistance to motion of a vehicle so as to balance more efficiently between front and rear pad brakes hence better braking performance plus reduced stopping distance. The danger about getting rear wheels locking up before the front ones is that it creates very precarious situations such as tailspin and U-turns, hence necessitating the use of braking match valves.

What are the symptoms of a faulty brake proportioning valve?

The valve is a major part of regulating pressure and keeping the right balance between front and rear brakes at all times. It helps in avoiding wheel lock or loss of control while using the brake pedal. When the valve goes bad, certain problems are most likely going to be experienced.

Accurate identification of these symptoms is important as failure to do so can lead to unnecessary component changes and ignore issues that need attention in brake system.

Rear wheel locks during heavy braking

You͏ are driving down a wet highway when all of a sudden the car in front of you stops short. Naturally, you slam on the brakes. Instead of your vehicle slowly coming to a stop, it gets stuck in rear-wheel lock and begins to skid out of control. Most times, if this resultant condition is felt then there is something wrong with the proportioning valve and it means that both rear wheels will get an opportunity to lock during emergency braking because of improper distribution of brake fluid pressure.

Should this valve get stuck, it may cause the rear brakes to engage and stay locked even when the brake pedal is not applied. Apart from being a very serious road safety hazard, it increases the risk of a loss of control accident through vehicle skidding. A vehicle that has tendencies of locking up its rear wheels is amongst the major signs that will indicate a faulty proportioning valve and thus needs an urgent inspection together with repair.

Uneven braking performance and vehicle pull

If you experience uneven braking, such as the vehicle pulling to one side when stopping, this may indicate that the combination proportioning valve in the brake system is not functioning properly. This can make vehicle control difficult and increase the danger of emergency braking.

Problems with the brake proportioning valve may manifest as:
Longer distance required to stop
The vehicle tends to drift in one direction when braking
Premature wear of the rear brakes compared to the front brakes
The presence of contaminants in various components of the brake system

These obvious symptoms indicate that frequent problems due to erratic braking performance may indicate that there is a problem with your vehicle’s proportioning valve, which requires prompt evaluation and repair if necessary.

PV6070MOP

Excessive front end dive

Nose dive occurs when the front of the vehicle leans significantly toward the ground during braking, indicating uneven pressure distribution in the brake system, often associated with a faulty proportional valve. This problem indicates uneven pressure distribution in the brake system between the front and rear brakes, which is often a sign of a malfunctioning proportional valve.

If braking power is uneven due to excessively reduced or clogged proportional valve pressure affecting the rear brake pressure, it can cause the vehicle to rely excessively on the front brakes. This imbalance can affect handling and safety, so you should immediately be alert to these symptoms when braking.

Summary

If you experience problems with the proportional valve, have it inspected and replaced immediately by a qualified technician. Proportional valves directly affect the effectiveness and safety of your vehicle’s braking system. As a trusted automotive brake parts supplier, Hipsen is committed to being the guardian of vehicle safety and providing you with personalized solutions for various types of oem brake parts. Our partners include Cardone, Electra Meccanica, Ford Otosan, Hayes, Knott, Polaris-Vector, and are trusted by major automotive brake parts repair retailers around the world.