Any ideas on this one?
Just got into my 124 Chassis 4Matic and shortly after start-up the triangle in the dash indicating activation of the 4Matic system stayed illuminated. The actual 4Matic dash idiot light is not illuminated. The car seems to run rich as well. I think its the overload protection relay but was looking for additional ideas. Incidentally the ABS idiot light is staying on as well!!
Any experts out there?!
Yeah your right about being overly complicated. The system is a complete nightmare. Multiple sensors and computers for all the different functional stages of engagement. What a mess!! I think I'll try the Overload Relay first since it's readily accessible.
Problem was the overload protection relay after all. Got lucky on this one I think. Hopefully this system will behave at least through this winter. I would recommend anyone with a 4matic to carry one as a spare since they seem to go bad often enough! Another symptom that I forgot to mention in my initial thread was that I had noticed the check engine light on with the car off!! Very strange that somehow there was a back feed in the circuit to trigger that gauge. Now that's fixed as well!!
Last edited by johneurostar : 11-10-2006 at 02:38 PM.
This is a perfect example of why overvoltage protection "relay" is a misnomer. You ever take a look inside one of those things? Or the fuel pump "relay?" Please... Those things are just loaded with components: resistors, diodes, capacitors, relay contacts and coil (of course) and even an integrated circuit chip. And they do so many things it's surprising. It continues to baffle me whay they are called relays. Full control module is more like it. Calling the fuel pump relay a fuel pump module makes it easier to pay $120 for one :-)
4 Matic Wagon Malfunction!! 
Linear Mode
