CL55 dead after ECU work (and gearbox probs!)

[Maff]

I took the car into Birds last week to get the ECU re-mapped and the limiter removed; however after half a day they killed the car completely. Wouldn't even start.

Read on if you've 15 minutes to spare!! (This is what I have gathered and been told so far....)

To cut a long story short they uploaded via the OBD2 port the modifications to the ECU, which caused the problems. Loads of errors and the car refusing to start. After some fault finding they decided to restore back to the changes they had for a standard CL55 (i.e. how mine was when I dropped it off to them)

However this *still* caused the same problems with CANbus errors, car refusing to start and more.

Scratching heads and Bird's getting seriously worried that they were going to have to buy a new ECU, they then took the ECU out of the car and dropped it off at a specialists who can program directly onto the ECU without going via the OBD2 port.

They completely re-flashed it with the default software. This restored the car back to normal and all was OK.

Today we found out the cause of the problems......

AMG in their wisdom created TWO versions of ECU software with the same filename for the CL55. An early version (2003), and a more recent re-map version. They only found this out when looking at the code, they found the differences: same filename, but different file sizes, checksums and coding dates etc.

Birds were uploading ECU changes only compatible with the latest AMG code, whilst my car had the earlier code! Hence all the problems as the new changes completely corrupted the ECU.

My car now has the latest AMG ECU code, however the power generated by the engine has an impact on the gearbox.... The 5-speed box's have an onboard ECU which monitors the amount of power being pushed through from the engine, and when this power/torque limit is exceeded, the gearbox throws you straight into neutral. (So I’ve been told) So every now and again when I put my foot down the gear box decides it's had enough and goes into neutral!! Not often, but three times so far.

This can apparently be fixed by new gearbox ECU software that is being uploaded on Thursday, and the new limiter is being programmed on Friday.

Fingers Crossed!!!

 

[KillerHERTZ]

tsk, thats what you get for buying a cheap car

 

[C240Sport97]

what happens to your MB warranty as a result of all this?

 

[Shude]

Hopefully this will be a cheap job after all the messing around!

 

[guydewdney]

it throws the box into Neutral - scary! im surprise that it would do this and not reduce the power like the LIM system or the ESP system..


scary if you are just overtaking a lorry or somthing..

 

[Brian WH]

it throws the box into Neutral - scary! im surprise that it would do this and not reduce the power like the LIM system or the ESP system..


scary if you are just overtaking a lorry or somthing..

It would worry me mate, that is when you need the power, to get out of trouble.

 

[Maff]

what happens to your MB warranty as a result of all this?

The MB Warranty is still in tact, it's upto MB to a) detect the ECU work which is very unlikely (generally if MB suspect an ECU problem they either re-flash it or order a new one!) and b) if they do detect the work prove that it is that which is causing problems with the area they are fixing.

Also, the work being is covered by a three year warrantee too.

 

[Satch]

the power generated by the engine has an impact on the gearbox.... The 5-speed box's have an onboard ECU which monitors the amount of power being pushed through from the engine, and when this power/torque limit is exceeded, the gearbox throws you straight into neutral. (So I’ve been told) So every now and again when I put my foot down the gear box decides it's had enough and goes into neutral!! Not often, but three times so far.

QUOTE]

The prospect of going into the big N at a critical moment is indeed a worry but I would be more concerned as to why AMG engineers felt such a very firm intervention needed be either retained or built in. At a guess there is some danger of exceeding the nominal power & torque rating of the autobox and drive train in general.

Now I am sure that MB use a somewhat cautious rating but all the same I think I would like to know what it was and compare that to the modified output before removing that particular feature!

 

[GrahamC230K]

Scarey stuff, but nice one for going through with it!

 

[GordonTarling]

I used to own a Volvo V70 T5 which had a nasty habit of going into neutral when you least needed it to - VERY dangerous in many situations and I'm glad I got rid of it.

 

[glojo]

what happens to your MB warranty as a result of all this?

I think it is all about freedom of choice. Maff has gone into it with his eyes wide open, I would have thought Mercedes-Benz would have equipment that would be able to give hte complete history of the highs and lows of the engine, plus what cut outand when. The average dealer equipment might not, but I believe the Milton Keynes technicians have different diagnostic equipment.

Good luck with the car Maff

Regards,
John

 

[Robbo]

Stupid question, but isnt the car fast enough as it is in stock form?

 

[mark.t]

mb surf

i wonder if mb surf this site

 

[glojo]

i wonder if mb surf this site

Nah!

Just Greenoaks of Maidenhead

John

 

[mark.t]

and Milton Keynes

 

[Robbo]

and Milton Keynes

I would be amazed if they didn't! An excellent way for them to find out what the average punter thinks about the marque.

 

[Maff]

Stupid question, but isnt the car fast enough as it is in stock form?

After a month of driving it already starts to feel slow

Gone back to the Golf Diesel for some real torquey driving! (just done 200 miles in it today and still amazed by it's pulling power and speed)

 

[saorbust]

Dumb question, but given the ECU for the engine and gearbox are seperate, would it be wise to see if any other ECU's need updating as well ? I wouldn't want to have the chips on potentially incompatible versions...

 

[Maff]

Dumb question, but given the ECU for the engine and gearbox are seperate, would it be wise to see if any other ECU's need updating as well ? I wouldn't want to have the chips on potentially incompatible versions...

It's at Mercedes today having everything double checked software wise, followed by an extended test drive and then diagnostics to see if any errors/faults have been logged in the ECU's.

Should hear back tomorrow...

 

[Flash]

Maff,

R Mercedes charging you for the checks etc. or are you getting it done under warranty?

Have you left it with the local Dealership group in Berkshire that there have been quite a few threads on?

Flash