Mercedes V Klasse Ignition Problem

Okay, that sounds like a frustrating problem. Terminal 15 refers to the switched positive power supply that comes on with the ignition. The error suggests a break in that circuit. Since you mentioned the fuse box, definitely check the fuse specifically for the ignition system or Terminal 15. Consult your owner's manual for the correct fuse location and rating. A blown fuse is the easiest fix. If the fuse is good, the problem could be with the ignition switch itself, the relay switch that controls power to Terminal 15, or a break in the wiring between these components. Do you have a multimeter to check for voltage at different points in the circuit?

A multimeter, huh? Never used one of those. Where exactly should I start poking around with it? Is there any specific relay switch I should be looking for? I'm not that familiar where the ignition switch is exactly.

I understand. Using a multimeter can be tricky if you haven't done it before, and without specific knowledge of your V Klasse's wiring diagram, it's hard to pinpoint the exact location. It's also possible that the error's 'likely cause' is what's happening with the cable or plug connection of the component. Given the symptoms and the potential complexity, it might be more efficient and safer to take it to a workshop. They can diagnose the issue properly and avoid any further electrical damage. It's frustrating, but sometimes professional help saves time and money in the long run.

You're right, I took it to the shop. Turns out it was a corroded connector on the ignition switch. They cleaned it up, and everything's working fine now. Cost me 95€, but at least it's fixed. Thanks for the advice!