GLS Tire Pressure Warning Light Issue

A faulty tire pressure sensor can trigger such errors. Considering your GLS's age, the sensor batteries could be reaching the end of their lifespan. Like any battery, they eventually lose their charge. Does the error message specify which tire is supposedly low, or is it a general warning?

The error message doesn't specify a particular tire, which is frustrating. Can I pinpoint which sensor is acting up without replacing all four? I'd rather not do unnecessary repairs.

Without a specific tire indicated, it complicates things. Some advanced diagnostic tools can individually read each sensor's signal strength and battery level. If your tool doesn't offer that functionality, visit a workshop. They can use professional equipment to precisely identify the faulty sensor. If it's the sensor battery, a complete sensor replacement including installation and programming will be around 280€.

I had a hunch it was going to involve a workshop visit. Your advice about pinpointing the exact sensor saved me potential headache and expense. The workshop confirmed it was a sensor battery. I replaced the faulty sensor, including the air valve, and recalibrated the system. The error's gone, and the car's happy again. I appreciate the help!