How to Solve Multiple Warning Lights Issue in Audi Q8
Modern vehicles are built to satisfy insanely high standards. As a result of which, they hardly ever break down or develop faults. Even if there is an issue in the vehicle, it is rare and highly unlikely if the car is relatively new.
So, if a problem arises in a vehicle, which is less than five years old, there is a cause for concern. Unfortunately, that is exactly what happened with one of our clients.
Mr. M recently bought a 2019 Audi Q8 after hearing positive reviews about the SUV’s reliability and performance. However, within a few months of purchase, the vehicle started to show multiple warning lights on the dash.
Our client was shocked and confused at the same time. After all, how could a relatively new SUV develop a fault so early? Was the fault already there when he bought the vehicle? Are Audis unreliable?
A plethora of questions filled Mr. M’s head and he couldn’t find answers to any of them.
In that case, there was only one thing left to do and that was to consult a certified professional. Instinctively, Mr. M visited an Audi dealership in search of a solution. But to his dismay, the brand’s dealership was unable to provide him with a satisfying answer. In fact, they led him to believe that it was his fault since he installed aftermarket tyres on his Q8.
The larger-sized rims were disrupting the sensors, leading to incorrect readings and warning lights on the dash.
Mr. M suspected foul play and left the dealership to look for more viable solutions. That is when he came to RM Motors, where our team of Audi experts started inspecting his SUV.
The team immediately developed a few theories and began working on them to provide a speedy solution.
What We Found
The initial diagnosis from our technician turned up a few error codes. Only some of them were relevant to the problem while the rest were there as a result of the core issue. The error codes were as follows:
- 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
Our Audi expert observed something interesting, that proved to be the defining factor in solving this case.
The two relevant error codes C0508 00 and C1035 15 were logged in separate modules. One of them pointed toward the ABS module, while the other concerned the Chassis Control Module.
The several other unrelated codes were ignored since our technician saw them be the result of the problem and not the cause. This, of course, helped our technician to focus on diagnosing the actual issue.
Diagnosing the Problem
At RM Motors, we adopted a highly effective 15-step diagnostic procedure that allows quick and accurate diagnoses of complex problems. The Audi expert technicians working at our garage, use it as the primary tool to search for the root cause of any issue. It helps them pinpoint every problem area, resulting in full coverage.
The technician working on Mr. M’s Q8 adhered to the same principles and started with the initial inspection. He had to ensure there were no electronic malfunctions in the dash that would trigger the warning lights to illuminate. Fortunately, that wasn’t the case and the technician decided to move further in the process.
Next up was a full scan of the ECU. Sure enough, several fault codes popped up, out of which only a few of them initially seemed relevant to the issue. Regardless, we had to be sure and so our Audi expert weeded out the unnecessary codes and found all the ones that were pointing to the problem.
The two main fault codes pointed to the suspension and the ABS on the right front end of the vehicle. Something was troubling the sensors in that area, enough to illuminate the warning lights in the dash.
Finding the Solution
The error codes mentioned that the warning lights came on only as a result of a problem in the right front end of the SUV. In other words, whatever the guys at the dealership were saying earlier was wrong. That’s because, if the aftermarket tyres triggered the sensors, the fault codes should have pointed to all four wheels and not just one specific area.
The previous diagnosis would be acceptable if Mr. M had fitted his Q8 with a larger wheel only on one end and not the others. That sounds outrageous, to say the least, so our technician moved on to test other possible theories.
He checked to see if the sensors were transmitting live data to the ECU. Interestingly, both sensors were unresponsive. In other words, the sensors either weren’t working at all, or the wiring was faulty.
To find the truth, our Audi expert began a physical inspection of the right front end of the vehicle. The sensors were not working. Perhaps, due to faulty wiring? Our technician dove in deeper and pulled out the wiring harness that connects both the troublesome sensors to the ECU.
He consulted the ELSA Pro workshop manual (Audi’s official documentation) to locate the harness and separate the live wires from the rest of the bundle. The wire coming from the power supply and the earth wire were both different for the two sensors. That is not something uncommon, since the two sensors report to their respective modules.
Our technician determined that the wire that goes through the plenum chamber had disintegrated in several places. There were visible gnawing marks on the wires. Perhaps, a rodent had a nice meal a few days ago, which led to Mr. M’s headache.
The bite marks and the damaged housing also proved all the other signals in the dash. Therefore, our technician moved on to the repair.
The Repair
After the 15-step diagnosis was complete, the technician started to make the repairs. He replaced the wires where needed and repaired the rest so that no wire was left uncovered. Once all of that was done, we rescanned the ECU for the relevant codes, and sure enough, nothing turned up this time.
Satisfied with the repair job, our technician handed over the keys to Mr. M, who couldn’t believe his luck. If he hadn’t come to our garage, he might have had to buy brand-new rims for his Q8. Thankfully, none of that came to pass. We salvaged the day for Mr. M, all thanks to the commitment shown by our professional staff.
Our Commitment to Clients
RM Motors is a garage that takes pride in imparting the best service to our clients. We want your satisfaction, which is only achievable if we work hard and train our staff to the maximum.
At RM Motors, you get a friendly atmosphere, where you can discuss your vehicle’s issues without any judgment. If that is what you desire and you are not getting it anywhere else, it is time to pick up your phone and call RM Motors at 01924 456666. Book your appointment now and talk to our team of Audi experts about your ailing vehicle.
