Mercedes Key Fob Not Working – MB Medic Mercedes-Benz key fob not working? The first thing you need to do is change the keyless remote battery. We assume you have already done that part by now. Is your Mercedes key fob not working after a battery change? This article will help you troubleshoot problems where the Mercedes key fob doesn’t work or no longer unlock/locks doors or trunk. Open Mercedes Key FOB (Old type) - YouTube Click to view on Bing2:39This video shows how to open old Mercedes Key FOB and take out its circuit. Suitable for battery change or entire outer shell replacement. Very detailed vide..Author: Flip KeysViews: 99K Symptoms of a Faulty Ignition Key in a Mercedes While there could be simply an issue with the key or key fob itself, there are other reasons why your ignition key might not work properly. One of the most common reasons why your Mercedes’ ignition key might not be working correctly is due to a faulty ignition switch. Faulty ignition switch KEY FOB replacement and programming | Mercedes-Benz Forum The blade of my key FOB broke off from the FOB and you can buy a replacement blade for ~$50 and they will repair it for free seems like a common tactic for the telling you that you need a new set of FOBs once your blades broken, it's not true. Mercedes-Benz C-Class: Fuse Diagrams and Commonly Blown Fuses Mercedes-Benz C-Class: Fuse Diagrams and Commonly Blown Fuses. Locate your fuse boxes, and become current with fuse sizes as well as color codes. Conduct fuse testing to find blown fuses. Gain the capacity to replace your fuses, and the potential to insulate yourself from shocking repair bills. Keyfob circuit schematic | Mercedes-Benz Forum Ok, so I know very well that Mercedes has stopped producing keyfobs for our cars... So instead my question is about repairing an existing keyfob? Various youtube videos shows people doing circuit repair and getting their keyfobs to work again. I was wondering if anyone has a circuit schematic..