A 170 semi-auto ECU failure

[gumbo]

Hi All,

A newbie hear with a major headache. The wifes A-170 semi auto refuses to go into gear. Mercedes main dealer have identified that it requires a new ECU, clutch? and possibly slave cylinder.

They have priced at £3,500. Best alternative found so far £3,100 from an independent gearbox outfit(not Merc specialist).

Any ideas best way to proceed, other than sell for spares or repair? Registered in 2000, paid around £4,000.

Any ideas appreciated.

Thanks

 

[television]

Wait till BlackC55 comes on,he is a MB engineer and runs one

 

[mattkh]

Hi All,Any ideas best way to proceed, other than sell for spares or repair? Registered in 2000, paid around £4,000.Any ideas appreciated.
Thanks

Hi
ECU can be repaired. What is the mileage? How much will you get for it if you decide to sell it for spares?

 

[jibcl500]

Will go out tomorrow and check it out, would it be possible for the headlamp switch to cause this.

jib

 

[gumbo]

mileage is roughly 70,000 (can't confirm as in the garage!). distress sale for spare / repairs you probably have a better idea than me. not in a position to strip and sell individually so ebay or similar - maybe £500 - 1000?

 

[Koi]

The semi-auto clutch is renowned for failing. I used to own one (from new) & it was on it's way out just before I sold it (approx. 38,000 miles).
So, if you get it repaired my advice would be to sell the car before it gets anywhere near the next 38k miles.

I believe MB stopped producing the semi-auto box because they didn't want the expense of fixing the problem.

 

[jibcl500]

I wouldnt think its worth repairing, might best to ebay it with a full description and go from there.

Is it poss to put a 5.0 V8 in an A Class?


jib

 

[BlackC55]

By ECU do you mean Engine control unit????

Ask the dealer why. As I see no connection between going into gear and engine control.

 

[jberks]

Doesnt the gearbox have its own electronic control box?
Anyway, what I find odd, is that all 3 items have gone. Ok, the clutch goes, ok the slave and ok the ECU but unless one causes another to fail, this is one hell of a co-incidence.
What is the parts breakdown? I can accept the clutch burns out but presumably they aren't that crazy. The ECU can be fixed for a couple of hundred, IF its failed and why would the slave cylinder go? and if it did, surely a recon of used one would do?
The whole thing makes no sense to me.
Worst case, I'd be looking into converting it into a manual with used parts but I can't see why it would be as bad as described and I'd be looking for one or two more opinions.

 

[gumbo]

looking back on my notes, have got ATE unit? My terminology probably at fault calling it ECU, from their desciption it was the unit that controls the gearbox. Sorry if sending people off in wrong direction!

 

[BlackC55]

Why would all three things go wrong?

Seems a bit suspect to me.

 

[jonathanjhann]

If the gearbox fails to go into gear, the faulty part is almost sure to be the semi auto control unit, located up under the left front wheel arch liner.
Remove the liner, check the electrical connector, try disconnecting, checking contacts and see if the clutch now operates.

This is the unit that receives the various signals from various sensors then converts it into hydraulic actuation pressur to operate the clutch.

To replace unit parts = approx 1700

 

[gumbo]

Thanks. That ties in with a local indi MB specialist who have suggested a price around £2,000. Current plan is to let them have a look so they can firm up on price and then take a view.