My W221 Mercedes Headache Hell ! HELLLLP

[Shmeefly]

Hi Guys

Right this post is going to be a challenge and probably a lengthly one but I really need all your help.
I saved up to buy a mercedes S class w221 because I've always wanted one and found a 2009 S320 CDI on gumtree which had been in a crash (front drivers side) and been repaired, it was a good price but he said the conductor plate in the gearbox needed replacing because the TCU was faulty. So I researched online on how to replace this part and from the videos I watched it seemed to be quite strait forward, he said it was drivable and so I traveled 200 miles to go and view it and it seemed to be in mint condition and started and drove quite well apart from when you stopped you had to put it in park and then back into drive otherwise it seemed really sluggish to cycle trough the first few gears, so I thought this was ok and would make it back to my house. I drove it all the way back without any problem UNTIL..... I got home and turned the car off but then it wouldn't start again ???? after quite a few tries it started but once turned off has not started again since !. I am quite mechanically minded and have rebuilt a few engines in the past and fixed/service all of my cars for the last 15 years but this has lost me!! at first I thought maybe the battery was the culprit but nope, then replaced the starter motor but nothing (I have another post with a video regarding this starting issue). I ended up deciding to buy a star diagnostic system, it arrived and a few errors were present one of which was a module under the dash drivers side wasn't communicating correctly or wasn't married up to the ecu correctly, and I'm sure I read somewhere if you replace this module it will start the car 40 times but only this many until installed correctly, also the error for the tcu was saying it cannot communicate with the ecu....So before I attended to these problems I decided to pull the dash out and reinstall it because it wasn't fitted correctly at all by the previous mechanic and there was airbag errors and I wanted to also check he had installed and connected all these correctly, all went well until I asked a mate to give me a hand over the weekend to reinstall it all, was going well until I went to get some grub for us and he plugged the white plug with the black and white wires which goes into the bottom of the cd/dvd unit into the INSTRUMENT cluster !! and turned the ingnition on ?!?!?! anyway I got back and he explained what he had done because he couldn't find the correct wire which went into the back of the instument cluster and that was the only one that fitted !?!?! Grrrrrrr I immidiately dissmissed him from helping me and installed the rest myself and now the navigation screen does not light up steering wheel does not respond, gear shifter does not respond or change onscreen like it did before and none of the buttons in the middle of the two screens dont work either ??? :-( I am gutted with all this and desperately need help and advise, I asked a local Mercedes garage to sort it out for me and he refused to touch it or even look at it, said he has been stung by these W221's before and wont go near them again ?!?!?

 

[whitenemesis]

Sorry TLTR, especially without paragraphs

 

[richard]

First you need to check every fuse in the multiple fuse boxes. If you are very lucky your friend just blew some.

Then you need to plug in your Star Diagnosis, do a Quick Test, see what ECU are non-communicative, and work out what is wrong. Then work on fixing all the errors that are 'F' (i.e current) unless you know they are not important or the reason for them

W221 is complicated and there's not going to be many people who will touch it after dash has been out and back in and mis-connected as you are now in the realms of someone who understands the electrics well - Another real issue is the cost of parts though. It was a very expensive car new and parts don't really get cheaper as car gets older (except for service parts as others start making clones, (air filters, brake pads).

If you can get it to Lightwater, we can work on it, but its probably going to cost significant money unless you are very lucky - and there is no way to estimate the cost in advance given no idea what is broken or disconnected, and it may be the dash out again ... And we don't do mechanical stuff only electrical so wouldn't touch the gearbox solenoid plate.

If this is the car that has an extra airbag in the dash that shouldn't be there - given the extra info above it seems to me that it has had a replacement dashboard - probably because the passenger airbag went off ...

There are a number of other professionals on here that also may be happy to look, such as Ollie at Prestige, but many may give you same reaction as your local Mercedes garage.

Cheers

Richard

 

[Shmeefly]

Sorry TLTR, especially without paragraphs

Sorry was on a rant

 

[Shmeefly]

First you need to check every fuse in the multiple fuse boxes. If you are very lucky your friend just blew some.

Then you need to plug in your Star Diagnosis, do a Quick Test, see what ECU are non-communicative, and work out what is wrong. Then work on fixing all the errors that are 'F' (i.e current) unless you know they are not important or the reason for them

W221 is complicated and there's not going to be many people who will touch it after dash has been out and back in and mis-connected as you are now in the realms of someone who understands the electrics well - Another real issue is the cost of parts though. It was a very expensive car new and parts don't really get cheaper as car gets older (except for service parts as others start making clones, (air filters, brake pads).

If you can get it to Lightwater, we can work on it, but its probably going to cost significant money unless you are very lucky - and there is no way to estimate the cost in advance given no idea what is broken or disconnected, and it may be the dash out again ... And we don't do mechanical stuff only electrical so wouldn't touch the gearbox solenoid plate.

If this is the car that has an extra airbag in the dash that shouldn't be there - given the extra info above it seems to me that it has had a replacement dashboard - probably because the passenger airbag went off ...

There are a number of other professionals on here that also may be happy to look, such as Ollie at Prestige, but many may give you same reaction as your local Mercedes garage.

Cheers

Richard

Thankyou sooo much for taking the time to read my rant, I have checked both fuse sections in the dash, both under the bonnet and the one in the rear of the car and nothing has been popped and I can also hear the cd drive rev down when in the car so it seems there is power ? and yes it was the one with the extra bag in the dash oh and to top it all off now I stepped out of the car catching the RJ45 cable went flying and ripped the bloody network port out of the C5 so going to have to send that back now before I continue attempting to diagnose my car ! I can honestly say I've never had so much bad luck in my life :-(

 

[Shmeefly]

I have a feeling the mistake my mate made may have fried the instrument cluster so my question to you clever lot is if I buy a second hand one from ebay will it just plug and play or will I have to marry it up with the ecu ?

Thanks

 

[whitenemesis]

Pretty sure it will need some coding to set the mileage etc..

 

[rls]

I changed the cluster in my old Viano to upgrade to the facelift version, you need to get the replacement cluster ‘virginised’ so the car sees it as a new cluster, then program it to the new car, I used a guy in Birmingham, just google mileage correction service.....


Sent from my iPhone using Tapatalk

 

[rls]

You could do the second part with your star if you have offline programming enabled, might be best to go to someone that’s done it before though


Sent from my iPhone using Tapatalk

 

[Shmeefly]

I changed the cluster in my old Viano to upgrade to the facelift version, you need to get the replacement cluster ‘virginised’ so the car sees it as a new cluster, then program it to the new car, I used a guy in Birmingham, just google mileage correction service.....


Sent from my iPhone using Tapatalk

I figured this might be the case and thanks for your imput will google that now

 

[Shmeefly]

You could do the second part with your star if you have offline programming enabled, might be best to go to someone that’s done it before though


Sent from my iPhone using Tapatalk

So should I assume I cannot virginise it ?

 

[rls]

I believe you need to program the chip directly on the cluster, so that bit needs specialist hardware, unless anyone else knows different....
When the guy did mine he took the cluster into his van, did some stuff then plugged it into the car and Star did the rest...I waited in the van so not sure what he did !


Sent from my iPhone using Tapatalk

 

[Shmeefly]

So as an update guys I purchased a second hand speedometer and installed it with one of those can filters and it worked great but didnt fix the problem I have with a dead nav screen, dead center console controls :-( any ideas guys ??? and has anyone got a wiring diagram which can tell me where the wires go from the main command/cd changer unit please as this main lead with the red/black wires seem to be the cause of these probs

Thanks

 

[richard]

It goes to the rear fuse box behind the rear armrest cubbyhole

If you look at the fuse box in the middle are a few relays. It’s the 7.5 amp fuse to the left of the relays.

R