View Full Version : Wiring Harness Issues - What do I look for when considering a 500E?

08-06-2011, 10:57 PM
Hello All,

I've owned a 500E and 400E, and I am getting the itch to own another 500E.

I remember posts about harness issues. Did the factory ever decide to replace them?

What are the symptoms of a bad harness?

Do I just visually inspect all of the wires under the hood?

If a 500E drives out properly what should I still be sure to check that is a 500E specific issue?

Thank you,


08-07-2011, 11:41 AM
Hi Robert,

The original harnesses all had defective insulation. The replacements available from MB have improved insulation. The harness is only ~$600 or so, and IMO is not a deciding factor when purchasing a car. Of course it's nice if a car already has the new harness, but it's a few hours DIY work to swap it out. Symptoms are generally along the lines of occasional misfiring or rough running, along with random error codes. Search the forum for more info, there is a thread with photos of what to look for - it's a fairly easy visual inspection at the injector wires, also the cam solenoid wires, and temp sensor wires.

There's not much to look for that is 500E-specific, just the usual W124/M119 stuff... fluid leaks, fan clutch, running too warm, AC working or not, center vents working normally, no clunking from the rear SLS shocks, normal power, no shift flaring/harshness, etc, etc. Documentation of chain rail and/or chain replacement is a nice bonus though.

500E's are becoming rare enough that if you want one, I'd just look for the right color combo at the right price for the condition, depending on your budget. You'll be better off spending more up front for a well-maintained car than a cheap fixer-upper; although the former will likely cost roughly double the latter.

BTW - welcome to the forum!


08-07-2011, 02:28 PM
Yes welcome (back) to the 500E world. I think I remember you from Scott's 500Ecstasy forum, no?


08-07-2011, 04:13 PM
Yes welcome (back) to the 500E world. I think I remember you from Scott's 500Ecstasy forum, no?


Yes - that was a few years ago when I had a 500E