Stuck in limp mode need help.
 

So for my 22nd birthday I decided to ditch my ls400 and buy a big daddy pimpin 2002 S500 , it only has 131k and yet it's in limp mode (2nd gear) , I recently had my fuel pump go out and let the car sit for 9 days until I replaced the fuel pump. Next after all that she now doesn't display any gears on the dash and she's now giving me a p0600 Serial link code as well as the previous mass airflow code I negated to fix. So I've spoken to my dad and we replaced the 13 pin connector which did nothing by the way and I'm still confused on where to go next with the car please help.

Check the tcu in the engine compartment and look for signs of fluid entry

ok so I pulled it out and it's dripping I'm guessing oldddd transmission fluid , can I dry it and use it if it's automatically time for a new one?

Clean it with electronic circuit board/contact cleaner. Multiple posts on this. Search. You're not the first to experience this.

Here's one example:
http://www.benzworld.org/forums/w210...ml#post4582348

You can pull the circuit board out of the casing by using a flat head screw driver. Make sure it is circuit board cleaner because certain contact cleaners eat away at plastics.

You also need to change the electrical connector plug that's responsible for the fluid leak otherwise you'll have the problem again

Attachment 360903

They replaced that already, that is the "13 pin connector" that was mentioned in the first post.

Ok so I've been looking to buy another TCM , will a C class TCM with matching numbers work for my S class?

Cleaning usually works, is cheap and easy to do...

limp mode
 

my 2004 s600 got water in same area by dealer...went into limp mode...they blew it out with air and all workee good!

You need to find what transmission you have. Most likely a 5 speed 722.6xxx one. So you will need a TCU for that transmission. Theres no 7 speeds in 2002 right?

Okay so I bought a new TCM and put it in , My dashboard now finally shows the Gear indicator, yet it now shifts into reverse after 10 seconds , and and it's stuck in 3 or 4th gear now with a P0730 "incorrect gear ratio" , is it time for a new tranny or is it something I can just yank out the bottom of the tranny and fix?

Oh the dash doesn't show gear indicator? Your shifter module must be bad. Because there is no position sensor in the transmission that reports to the instru cluster. Only the shifter module does. Mines went bad a few months ago, limp mode, sometimes it works and shifts to 5th, then stays in 5th.

Dash is fine and the shifter module works for about 10 seconds until the car is supposed to shift

There's nothing wrong with your tranny , it is an electrical problem . You probably still have damaged parts besides the fluid filled tcm . Did you clean the wiring thoroughly and Completely ? If not there is still fluid in the wiring now damaging your new tcm

did your car ever run correctly when you bought it , or did you buy it with problems ?

Didn't clean the connectors to the TCM because they looked dry and it had no problems at all until I the fuel pump went out and the car Sat for 9 days

The way fluid gets into the tcm is that it wicks its way up the wiring so if you had fluid make its way to the tcm then there was still lots of fluid still contaminating it

please answer my question whether this car ever ran correctly prior to sitting for 9 days or did you buy it with problems ? Lots of people buy a Mercedes cheap with problems only to find out the problems costs thousands to fix

You have the wrong Tcu it's set up for a different gear ratio.

Car ran perfect when I got it , now it's just stuck in third and I've cleaned wiring now I'm just wondering do I just send it too Mercedes or I can fix it myself

Do I need to send it to get re programmed ?