How to Solve Braking System ABS Fault in Audi A4
Motor racing pundits and racecar drivers will tell you that accelerating a car is the easy part. You simply press the throttle and the vehicle goes fast. On the other hand, the hard part is pressing the brakes at the right time with the right pressure. If you miss by even a little, the wheels lock up and you slide straight or you don’t stop in time and crash.
In simple words, the better you stop the car the faster your lap times. But the same is true for road cars as well. Powerful brakes can save you from an accident and if you are precise, and have the skill of an expert, you may not need any of the technology now found on cars to help you out.
That being said, most of us don’t possess the skills of Lewis Hamilton and we would prefer all the help we can get – particularly when it comes to something as critical as braking. Afterall, your safety depends upon it.
The Anti-lock Braking System (ABS) is a driver-assist feature that allows you to brake without worrying about locking up and sliding, especially in rainy and snowy weather.
Nowadays, the ABS and its relationship with the braking system have improved to such an extent that you won’t find any modern vehicle without this technology. Modern drivers are also so tuned to the ABS that they haven’t developed the skill to achieve maximum braking without locking up. If you turn off the ABS, the unskilled drivers would easily lock up and get into an accident. That’s why the ABS should always be in working condition.
Unfortunately, one of our clients experienced this issue first-hand in their 2017 Audi A4 when they saw a warning light on the dash signaling an issue in the ABS. The brakes were compromised and the driver was exposed to dangers which were not to be ignored. The client had to be extra careful while driving to avoid pressing the brakes too hard.
Luckily, they came to Links Automotive at the right time and trusted our team to help them out. Our Audi specialist, Dan Hague, listened to the client’s complaints and worked up a test plan to tackle the repair.
Dan knew that there was something strange going on – a five-year-old car doesn’t usually develop such problems. Especially, and Audi!
Our Audi technician had to make sure and so he started with the verification phase, followed by the fault-finding procedure.
Faults Found
Our lead Audi technician had to make sure there was no gap in communication with the client. Sometimes, clients describe the fault differently which can result in our technicians taking a different route in their investigation, ultimately lengthening the lead time. So, Dan double-checked the issues with the customer and inspected the dashboard for relevant error messages.
Luckily, the ABS light was on in the dash and that corroborated everything the client had described. But to understand the problem even better, our Audi technician took the car on a short test drive.
The brakes were underperforming and the ABS was not engaging on a full brake press. The fault was definitely there and Dan confirmed it with his initial inspection.
He then moved on to scan the whole vehicle for fault codes. If the ABS light was on, there must be a fault code present, helping guide Dan to the problem area.
The scan turned up the following fault code:
- C11EC04 – Brake pressure sensor 1
This meant that there was something wrong with the brake pressure sensor. It was perhaps unable to judge the hydraulic pressure in the system, leading to erratic brake performance and ABS disengagement.
The brake pressure has to be perfect at all times, and if that is even slightly off-centre the brakes lose performance.
You can often cause this problem by not regularly checking brake fluid levels. But the problem with this Audi A4 was a bit different. Usually, a sensor-related fault code indicates a dirty or faulty sensor and that was Dan’s initial thought.
However, our Audi technician didn’t speculate and instead initiated the 15-step diagnostic procedure to cover all his bases.
Diagnostic Procedure
The in-depth diagnostic process is used by all the technicians at Links Automotive garage. We trust the procedure because the 15-steps never allow us to miss any faults. Even if there is a hidden issue in the car, it comes forward.
Dan used the same 15-step diagnostic procedure to make sense of the repair and verify that there were no other faults in the Audi.
First, he tested the wiring coming in and out of the sensor. The power line and the ground were all fine. Everything was in order, which allowed Dan to move forward with the diagnosis. He tested the sensor next and found that it had malfunctioned.
But why did the brake pressure sensor fail so soon in a vehicle that is only half a decade old? Our Audi specialist, intrigued by the situation, looked at the Audi Manufacturer information by using the ERWIN software.
He learned that this is a common issue with A4s of this generation. The information further said that if the problem is left to nurture for too long, then the ABS module also fails, leading to a module replacement.
Something like that isn’t cheap! So, it is better to take care of it early, rather than suffer later.
Luckily, Dan had caught the issue red-handed and concluded in no time at all! He only had to make a small repair and hand over the car back to the client.
Solving The Problem
Our Audi expert removed the faulty brake pressure sensor and installed a new one in its place. But he didn’t stop there. Since the pressure issue could lead to an expensive repair, Dan ensured the brake pressure is always optimal.
He installed a new ABS pump to the A4 and started programming the new pump to the system. It wasn’t long before the vehicle accepted the new replacement.
Dan took a sigh of relief and started to wrap up the repair.
Our Audi technician rechecked the car for fault codes and found no new codes stored on the system. Dan cleared the old codes and tested the vehicle for a working ABS. Fortunately, everything was working fine, the ABS was engaging on heavy braking, and the brakes weren’t locking the wheels.
Once Dan satisfied himself, he called the client and asked them to pick up the vehicle from Links Automotive.
Summary
A client drove into our garage, complaining about a warning light in the dash of their 2017 Audi A4. The ABS wasn’t working properly, resulting in the brake system losing performance. Our Audi specialist listened to the client’s complaints and initiated the 15-step diagnostic procedure to find out the root cause of the problem.
Our technician Dan, not only diagnosed the issue in record time, but he was lightning-fast in employing the solution. As a result, the client could return home with a fixed car in no time at all.
The whole repair took Dan two days, but the end result was first class – great service, great know-how and great value.
The motivation, commitment, and hard work that our technicians put into every repair are admirable. It is because of them that Link Automotive has made a name for itself in the local community.
If you want to experience great service that is great value, don’t look further than Links Automotive. We guarantee that, at our garage, you will get the correct diagnosis every time!
If you are looking for an Audi garage to service and maintain your vehicle, contact us at 01625 402262.
