danC250

A while back my 2014 C250 went into Limp Mode because of low transmission fluid levels. After a while it would not start at all. I had it flushed and battery renewed, but now it will not crank.

1. Turn key to 2nd position
2. Dash lights up
3. Everything seems normal
4. Turn key to start
5. No sound

The mechanic told me the TCU does not respond when he connects to it directly

He tells me everything else is fine and that hey cannot find any other problem. He says that there are no "shavings" in the transmission plate or something.

He is charging me $350 for diagnostics + $1400+tax for TCU replacement

He charged me extra to know for 100% that it is the TCU that is the issue, but tells me that he cannot get to the TCU because it is welded. I asked him how can he replace the TCU if it welded shut? He shut me down by saying something like "Hey you brought it into me. I tell you what it is. You can come and tow it out." Forcing me into a situation to make a decision when I want to know more.

I feel like it is something simple and they are just charging me for bull**** at this point. I have had it inspected by two mechanics already. The way they play mind games make me not trust them. And they have my car and I worry that they will deliberately do something to my car if I upset them. I hate being in this vulnerable position.

Can somebody help me, please?

Andy74

Dats the reason why I only use my MB dealer.

irondad

It's a 722.9 transmission and the TCU is inside the transmission. It is not welded in, but a massive pain to get out. Those transmissions are also notorious for contact plate issues. If you have Mercedes repair it you're looking at around $3,500. I've been there and done that. I'd get a Mercedes-specific code scanner and see what codes are displayed and post them here.

chassis

@danC250 Why do you think the low fluid situation happened in the first place?