Q5 Warning Lights Point to Dangerous Tire Issue

Having some experience with Audi vehicles, I encountered a similar issue with my A5 2013. Started with the same symptoms, ABS warning, heavy steering, and the tire pressure monitoring system showing warnings. Initially used a tire gauge to check pressures and found significant pressure loss in one tire. Even after inflating, the tire would lose pressure within days. The root cause turned out to be a defective tire valve, which was allowing air to leak slowly. The workshop diagnosed it quickly, low tire pressure was indeed causing all those warning lights and steering issues. The repair involved replacing the faulty valve and recalibrating the tire pressure monitoring system. Total cost was 280 Euro. Before jumping to conclusions about your Q5, could you share: Which tire shows low pressure? How quickly does the pressure drop? Are there any unusual noises when turning? Have you recently hit any curbs or potholes? These details would help determine if your issue matches what I experienced. While checking and adjusting tire pressure is a good first step, the multiple warning lights suggest getting it professionally checked might be wise.

Last service at 120899KM. Thanks for the detailed response. I checked all tires with a reliable tire gauge this morning. The front right tire shows significant pressure loss, dropping from recommended 2.4 to 1.8 bar in about 4 days. The tire monitoring system keeps triggering alerts. When turning left, there is a slight humming noise, but nothing too concerning. No recent impacts or curb hits that I can recall. Going to inflate all tires to proper pressure first to see if it resolves the ABS and steering issues temporarily. Getting the vehicle to a workshop soon seems like the smart move, especially since multiple systems are showing warnings. The tire pressure issue seems too persistent to be just a routine pressure loss.

Thanks for the update. Those readings from your tire gauge definitely point to a significant pressure loss, dropping 0.6 bar in 4 days is not normal wear and tear. On my A5, I noticed similar pressure loss patterns before discovering the faulty valve. The humming noise during left turns could indicate uneven tire wear caused by running on underinflated tires. The tire pressure monitoring system kept alerting even after refills, just like yours. While inflating the tires is a good temporary fix, the rapid pressure loss rate suggests either: A slow puncture in the tire, A damaged valve stem, A compromised tire pressure sensor The multiple warning lights (ABS, steering) are typical safety responses when the tire pressure monitoring system detects significant pressure differences between tires. My repair involved: Tire inspection and leak testing, Valve stem replacement, Sensor recalibration, System reset Cost breakdown for reference: Diagnostic fee: 80 Euro, Valve replacement: 120 Euro, System recalibration: 80 Euro Would strongly recommend getting it checked soon, as driving with consistently underinflated tires can lead to more serious issues with handling and tire wear.

I really appreciate your thorough analysis. After inflating the tires, I drove around for a bit and the ABS light temporarily went off, but came back after about 20 minutes. The tire pressure monitoring system is still showing warnings, and the front right tire already feels softer than the others. Based on your similar experience and repair details, this does sound like more than just normal air loss. The fact that my symptoms match yours so closely, especially with the quick pressure drop and multiple warning lights, makes me think I might be dealing with the same valve or tire pressure sensor issue. Going to book a workshop appointment tomorrow. The repair costs you shared give me a good baseline for what to expect. At least now I know what to mention to the mechanic about the pressure loss rate and warning light patterns. Better to get it fixed properly than risk damaging the tire or dealing with unsafe handling due to constantly underinflated tires. Since the tire gauge shows it losing pressure this quickly, I will keep monitoring and adding air until the appointment if needed. Thanks for helping me understand what might be causing all these connected issues.