How to Fix Multiple Warning Lights on the dash of an Audi Q8
Nowadays, modern vehicles are so heavily tested before release that it is rare to see them develop any issues. At least not in the first 2 or 3 years after production. It’s not unless you install unapproved aftermarket parts or make outrageous modifications to the car that something goes wrong.
The only other nemesis for an automobile’s reliability is old age. Relatively new vehicles don’t tend to get issues such as flashing warning lights on the dash. So, when our client experienced the latter in his 2019 Audi Q8, he was puzzled.
Why was he seeing so many lights on the dash when his SUV was only three years old?
To search for answers, Mr. M went to his local Audi dealership in Manchester.
Now normally, that can be a good thing – after all you would expect the main dealer to know how to fix their cars better than anyone else, especially the puzzling type of issues, wouldn’t you? But unfortunately, that was not the case for Mr M.
He was told that the flashing warning lights were a result of the aftermarket wheels he installed on his Q8. The dealership technician claimed that since the wheels were bigger than the manufacturer’s recommended specification, the vehicle was sending mixed signals to the ECU, resulting in a plethora of errors.
Mr M citing his previous experiences with the dealership decided to reject their diagnosis and find an alternate solution. He searched for a while and came upon Links Automotive, where he trusted expert technician Dan to inspect his SUV.
Dan was immediately on the task as he put his vast experience working with Q8s to the test.
What We Found
It didn’t take our technician too long to figure out the issue affecting Mr M’s Q8. Dan used the industry-standard diagnostic tool to look for relevant fault codes and hit the bull’s eye almost immediately. The scan showed the following error codes:
- C0508 00 – Wheel Speed Sensor; front right (short to ground)
- C1035 15 – Front Right Ride Height Sensor (open or short to ground)
- Multiple others irrelevant to the issue at hand
Interestingly, the two fault codes were logged in different modules. The one concerning the wheel speed sensor registered in the ABS Module. The second one, related to the ride height, showed up in the Chassis Control Module.
Dan also noticed several unrelated error codes, but he confirmed that they popped up only because the ABS and Chassis Control Modules were malfunctioning. So, after separating and identifying the important codes from the clutter of several others, Dan moved toward the 15-step diagnostic procedure.
Diagnosing the Problem
At Links Automotive, our technicians adhere to a 15-step diagnostic procedure that allows quick and accurate diagnoses of complex problems. It is a standard practice at our garage to run every issue through the comprehensive procedure, so our technicians miss nothing along the way.
Dan acted in accordance with the same series of steps and began his work by inspecting all the warning lights in the dash. His first job was to ensure there was no electronic fault inside the dash. Sometimes, only the light can malfunction, and a simple reset works wonders. However, that was not the case with Mr M’s Audi Q8.
Unfazed by the result, Dan moved on to the next step. He scanned the complete SUV for fault codes, and quite a few turned up, as a result.
The hard thing now was to filter the unnecessary codes and find the ones that were relevant or close to the issue. Luckily, Dan is an expert at this, and he wasted no time showing his worth. Our technician separated the necessary from the unnecessary in a jiffy, and soon a clear picture emerged.
The two problem codes were related to the suspension and ABS systems on the front right side of the Q8. The commonality of both these error codes helped Dan devise a plan.
Arriving at the Solution
Our expert technician deciphered one key thing from the complete scan. He confirmed that the problem only exists in the front right end, meaning the dealership’s initial diagnosis was wrong.
Why? Well, that’s because changing the wheel size should have activated a warning signal from all four corners of the vehicle. So, why was it only coming from one particular side? Mr M wouldn’t have changed to a bigger wheel on only one corner of the SUV, right?
Thereafter, our technician looked at the live data feedback from the two trouble-inducing sensors. As expected, there was no feedback from either of them. So, keeping all the new information in mind, Dan started with a physical inspection of the SUV.
He determined that both the sensors are located in the same corner of the vehicle, which means their wiring also runs through the same area.
Perhaps the wiring is faulty?
Assuming the same, Dan traced the wiring harness from the sensor back to the main power supply. He consulted the wiring diagrams found in the ELSA Pro (Official Audi) workshop manual and found that the two sensors belonged to the same wiring harness, but they had separate live wires stretching from each sensor head back to the power supply. Not only that, but the sensors in question had separate earth wires as well. That’s because the two sensors reported to different control modules.
Dan’s investigation revealed that the wiring harness was damaged in several places inside the plenum chamber. It was evident that a rat or some other rodent had the wiring harness for dinner. There were gnawing marks everywhere, and some wires were completely exposed to the SUV’s body. The damage explained all the different flashing lights on the dash and the various fault codes.
Once the problem was diagnosed and identified, all Dan had to do was mend the damage. He repaired all the damaged wires in the wiring harness and made sure no wires were left untreated. Once the solution was employed, our technician rescanned the Audi Q8 and cleared all the codes. On further inspection, neither the fault codes nor the warning lights returned.
Our technician used his expertise, knowledge, and problem-solving skills to get the solution in the least possible time. All of that was thanks to our staff’s commitment and the thorough use of the 15-step diagnostic procedure.
Dan completed his end of the bargain, and the vehicle was handed over to a very happy and satisfied Mr M.
Our Commitment to Clients
Links Automotive are able to solve these types of head-scratching automotive puzzles, thanks to the motivation of our technicians and support staff. We want only the best for our clients, but more than that, we want them to leave our garage happier than before. We strive for your satisfaction, and our technicians take the lead in that regard.
At Links Automotive, you get the high quality experience you deserve. It was what Mr M deserved and received. You can get more of the same, so what are you waiting for? Pick up your phone and call our garage at 01625 402262 and book an appointment for your vehicle.