Intermittent Brake Trouble with Mr A’s Q7
The Audi Q7 is one of the largest, most luxury German SUV’s that money can buy. It has been around for some time now, with recent models even sharing the same platform as the Porsche Cayenne and Bentley Bentayga. The Q7 needs to be smooth and refined to live up to its more expensive cousins.
Despite being 300kg lighter than the previous generation, the 2017 Q7 still weighs over two tonnes and needs the best in braking power for it to stop in a timely manner. Unfortunately, due to the complexity of modern braking systems, they sometimes become faulty.
With precision sensors, vacuum systems, and electronic pedal boxes, any number of issues can arise with the Q7 braking system. Here at Links Automotive, your Audi group specialist, our latest customer, Mr A, came in with intermittent braking issues.
Braking is not only a safety feature for vehicle occupants, but also a vital function to prevent accidents. Ensuring safety of other road users, infrastructure, and pedestrians. Without a functioning braking system, a car cannot stop in time, potentially causing serious harm to others. Plus, it is a failure on an MOT test.
Mr A came into our workshop at Links Automotive complaining about strange feedback when he pressed the brake pedal. This, combined with audible noise from pressing the brakes, and the message on the dashboard, caused Mr A concern.
Luckily, as we will find out, Mr A brought it to us at Links Automotive as soon as the faults appeared. Being an independent VW-Audi Group specialist garage, we are well equipped in being able to diagnose and fix any Audi braking issue.
At Links Automotive, we have the best-in-class knowledge and experience in repairing VW-Audi Group vehicles. Our technicians know how to fix braking, or any other type of issues with these brands.
Getting to the Source of Mr A’s Braking Issue
Duncan Conway was our Audi Q7 specialist technician working on this troublesome case. We knew Duncan could get to the root cause of the braking problem for Mr A and fix it with his vast knowledge in all Audi vehicle repairs.
Firstly, Duncan noticed the error code on the dashboard. Using his knowledge combined with our strict repair process we perform for all vehicles; he hooked up the ODIS specialist diagnostic tool and cross referenced the error code that displayed. Digging deeper, Duncan knew how to go into the ABS electronics module to see if anything out of the ordinary was displaying in the vehicle’s data.
As a result of Duncan’s deep dive, the C11EC 04 – pressure sensor for brake booster, internal system fault code was being flagged on Mr A’s Q7. Duncan also knew, from being an experienced Audi specialist, that this could lead to further problems with Mr A’s Audi braking system. The likes of “C054A 00: Vacuum sensor “A” Range/Performance” or “P050F 00: Brake Assist Vacuum Too Low” error codes could be manifested. Both of which can be an expensive repair, let’s explain why:
If the initial “C11EC 04 – pressure sensor for brake booster, internal system fault” was left too long without being looked at, the ABS unit can be damaged further. This is because the ABS unit cannot see the vacuum data from the sensor. As a result, a ‘hydraulic boost compensation’ is carried out within the ABS unit every time the brake pedal is pressed.
This was what Mr A had reported he was feeling/hearing. There is a limit as to how many compensations can be processed within the unit too. If the unit reaches this limit, the previous fault codes will be followed up by fault code “C123E F0 hydraulic brake servo limit reached” and the complete ABS unit must be replaced alongside repairing the original issue.
Duncan knew there was no way that Mr A could tell how close it was to the limit, as the dashboard does not give any indication. It was therefore very important that Mr A called us as soon as he saw the “Brake Servo restricted” warning on the dashboard, to allow us to do our best to minimise repair costs. Duncan, our Audi group specialist technician could then diagnose this issue and fix it straight away.
After the diagnostic scan, Duncan visually inspected the ABS unit and servo which turned out to be ok. Duncan investigated the fault code that was coming from the sensor. No data could be read from the sensor. Duncan took the sensor off the vehicle and tested the wiring and terminals – both of which were ok. He dug even deeper, this time using an oscilloscope. Confirming Live, Earth and Signal voltages, Duncan concluded that the sensor itself was at fault.
Replacing the Faulty Sensor and Resetting ABS Unit
At Links Automotive, we have only the highest qualified technicians who really care about the industry and customers’ vehicles. They have the best knowledge on VW-Audi Group vehicles, being a specialist garage that handles all sorts of issues – Mr A’s Q7 was no exception.
After the issue was found by Duncan, our Audi specialist technician, he went ahead and ordered the new replacement brake servo vacuum sensor. As it was already removed from the vehicle, the replacement was installed in no time, to enable Mr A to carry on with his day in his fully working Audi Q7.
The live data was checked by Duncan to make sure all functions on the braking system were working correctly. The fault codes needed to be cleared before a test could be performed.
Using the ODIS Audi dealership tool, Duncan was able to read live data from the brake servo vacuum sensor to confirm, using his expertise, that the unit was working again. To further gain confidence in Duncan’s fix, he took it out for a test drive to test the feel, noise, and braking performance of the entire system. The warning had disappeared from the dashboard, and never came back after the fix. The feedback on the brake pedal had returned to normal, and there was no noise coming from the braking system that would indicate any faults.
Our close relationships with local VW Audi dealerships and parts suppliers meant we were able to source Mr A a new brake servo vacuum sensor almost straight away. Meaning the problem could be identified and fixed in one day.
At Links Automotive we know as Audi specialists that communication is important. Therefore, Duncan and our team took Mr A through the entire process. After explaining to him that the servo sensor had been faulty, he was given an estimated time of completion with a breakdown of parts and labour costs.
As a result of us fixing it the same day, Mr A did not need one of our courtesy cars or to arrange his own transport. With our knowledge and expertise, Duncan fixed the issue by replacing the sensor.
Mr A was incredibly fortunate to have contacted us when he did – any delay would have resulted in a whole new ABS unit being required due to the nature of the fault with this Q7’s braking system.
You’re in Safe Hands at Links Automotive
As the brake system is one of the most crucial in vehicle and occupant safety, it was vital that Mr A got it fixed as soon as possible. At Links Automotive, we are the complete VW and Audi specialists. As a result, we can save our customers time and money by preventing bigger issues in the long run. With Duncan at the driving seat of trying to fix the problem with this Audi Q7, Mr A was back underway in no time.
Duncan was also able to tap into our network of Audi bulletins, parts suppliers, and his own experience to test and diagnose the problem. Quickly getting the replacement brake sensor to our workshop and replacing it all in a matter of hours.
Without the VW Audi garage manufacturer tool, ODIS, the car could not be reset either. Which is why at Links Automotive, we see hundreds of Audi customers each month and have the knowledge to fix a host of vehicle faults. Our Audi and VW Group knowledge sets us apart from other garages.
If you need your Audi Q7 looked at by an Audi specialist workshop because of intermittent braking issues, contact us today on 01625 402262 to book an appointment. We have the best customer service staff here to help at Links Automotive – your Audi Specialist garage.
