Doing their part to help the environment and meet European regulations, Mercedes have developed a new type of wiring that has wreaked havoc on successive generations of Mercedes owners. Like so many pervasive car problems, the real problems emerged long after any warranties existed. And in the 1990s, Mercedes developed a new type of wiring that was supposed to be degradable after the car’s lifespan expired. Mercedes had good intentions, but good intentions often have undesirable results.
While it’s hard to find credible reports on this problem, there are plenty of forums filled with mid-1990s Mercedes wiring stories with nightmare scenario wiring problems. It seems that as cars age, the wiring harness insulation breaks down prematurely, leaving what could be a cherry Mercedes sports car unusable due to electrical issues.
In a used Mercedes buying guide, Piston Heads warns of several issues with the Mercedes W202 model, particularly electrical issues due to biodegradable wiring, which they call its “Achilles heel”. YouTuber The Car Wizard displays a glaring example of a bad wiring harness in one of his videos that results in the need to replace the harness at a cost of over $10,000. The car in question is a well-maintained example of a luxurious V12 sports car that basically comes down to the extreme cost of repairs. It’s a shame that Mercedes created this problem, preventing some nice to drive Mercedes-Benz cars from continuing on the road.