mb'dak

I am having problems with the 4matic in my 1991 300TE. I have been able (in the past) to clear 4matic light by jumping 1 and 5 in the diagnostic port. No longer works--I do get 6 flashes but the light stays on. Hydraulic tank is full. What should I do next??

brakel8

Take it to someone who knows the system well, 4-matics can become expensive to fix very quickly. First have them try and pull codes, if code 1 is retrieved then it indicates a hydraulic problem at that point don't waste time and have a hydraulic pressure test done ( it should be around 180 bar). If there is no pressure then the pump is most likley bad (usually pumps go bad due to lack of fluid from a leaking transfer case). The most common issue is the transfere case, the seals go bad and the hydraulic fluid fills the transfere case. This can be checked by removing the fill plug (if fluid comes out, the seals are bad). Make sure the tires are the same brand, model and size all the way around and that they have about the same amount of tread otherwise it will turn on a malfunction light. Also have the charging system check, low voltage can cause an issue too. Good luck, hope this helps.

mb'dak

Thanks Brakel8. Did notice that without studs on last summer I was able to clear trouble lite. Went all winter with studs and no 4-matic--although wagon handles very well without 4-matic would still like to have it if its there.