Mercedes E Klasse hybrid electronic parking brake problem

That does sound frustrating. Modern electronic parking brakes can be quite complex. It's good you've already scanned for codes; that's a crucial first step. While a faulty motor in the caliper is a common culprit, it's not always that straightforward. Think of it like a circuit: the motor is just one component. Have you checked the wiring and connections to the caliper? A corroded connector or damaged wire could also cause the same symptoms. Also, is the brake sensor itself functioning correctly? Sometimes a faulty sensor can send incorrect signals to the control unit, preventing the parking brake from engaging or disengaging.

Thanks for the input I appreciate the 'circuit' analogy; it makes perfect sense. I haven't yet inspected the wiring and connectors directly at the caliper. I focused primarily on the error code itself. Regarding the brake sensor, is there a reliable way to test its functionality independently, or would that typically require specialized diagnostic equipment

Testing the sensor independently can be tricky without the right tools. A multimeter can sometimes give you a basic reading, but it won't tell you if the sensor is sending the correct signals under load. Given the symptoms and error code, and the fact you haven't checked the wiring yet, I would carefully inspect the wiring and connectors first. If those check out okay, then, yes, it's probably time to visit a workshop. They have the diagnostic tools to pinpoint whether it's truly the motor or a sensor issue.

Thanks again for the advice As you suggested, I took it to a local mechanic. Turns out, it was indeed the electric motor in the brake caliper that had failed. The wiring and sensor were fine. The total repair cost was around 505€, including the new caliper and labor. At least it's resolved, and the vehicle safety is restored.