Urgent help please :)

[SteveX]

Sometimes I amaze myself, all working. I decided to strip the old sealed unit apart and see what made it tick.

So I carefully took apart my old sealed unit, and upon striping it down realised that the sensor which was missing from the replacement unit was removable (as was the shaft that has the keyless go power and signal feed). I decided to take the other one back out of the car, and I ended up retrofitting the keyless go shaft and the keyless go sensor to the unit I bought from the Merc brakers that was fully working and guaranteed

I have a table of carnage but I now fully understand how they are put together. Essentially when I called Mercedes today they wanted £512, when all I needed was to replace a small plastic box with a gear and sensor in on mine. It's literally a generic part, the one I got from the C class is the same, even has keyless go power output and signal.

The base unit had the fitting point to mount the keyless go sensor to that detects when it is in P and can activate, and the case had the pre molded gap for the external plug to go into for the sensor fitment.

Quite chuffed, normal service has resumed

So I split an A209 267 03 24 and retrofitted it's working parts to an A203 267 60 24


Thanks.

 

[alexanderfoti]

Excellent work! I did notice those parts had MB parts numbers on them, but where not order able separately (when doing the 211 one).

 

[SteveX]

Excellent work! I did notice those parts had MB parts numbers on them, but where not order able separately (when doing the 211 one).

Yup well the odd thing is the one I bought had the innards printed with A203 or A209 part numbers on them, so clearly they used to be serviceable units, but the new ones are sealed and when I took it apart by splitting the adhesive from the base and top unit they no longer have part numbers printed on them.

I didn't know for sure what it would look like inside when I started, but I thought it was worth a try, I didn't expect the other one to be able to have the other parts retro-fitted but to my surprise they could be.

Here is the left over bits from the original box.

 

[SteveX]

This shows the sensor for keyless go, this was the plug I had no where to put when I fitted the new one in.

 

[SteveX]

It affixes with a pin going through the mounting, but the whole thing has to be taken apart to get the parts out to get the pin in.

It seems it's only function is as a fail safe to ensure that the keyless go system is certain the car is in park. The white rod is constantly pushed in when in all other places other than park, when in park it is allowed to spring out.

I had wondered if this was my issue, however, when trying the car with the other unit, this module did not even exist in the car. Whilst the entire keyless go system was rendered in-opperable as it did not have this sensor confirming the car was in park, the other sensor was working fully and transmitting the gear position to the car and able to go through all modes without fault. The keyless go module wouldn't jam the car in D, it can't it's just there to perform a function when it is in P, and seeing as D was always displayed on the cluster it couldn't work with the other unit (I hope all that makes sense).

As a backup, if for any reason it did interfere I could just unplug it like it was not there, but I was sure it was the gear position module at fault.

 

[SteveX]

Here are the two selector shafts, the keyless go one seems to be rare, it is hollow with a small circuit under the button and two small pins to connect.

 

[SteveX]

This is where the pin needs to go to affix the keyless go park sensor. It is only possible to remove or replace this by dismantling the entire unit to get the gear selector shaft out.

 

[SteveX]

Here is the A203 unit with the keyless go shaft and sensor retrofitted to it's gear shift selector.

 

[SteveX]

Fully assembled, cleaned and re-greased, ready to go in the car for a try. I drove all over town trying all the driving modes, shifting gears, starting and stopping, tested the keyless go and everything works. The other day I couldn't even get out of my road without it failing and getting stuck in D!

 

[SteveX]

So all in all a happy bunny, I'm not too keen on fitting SH parts, but it was guaranteed for three months, and I bought it as it was only £47 inc postage just to try to see if it would fix the gear selector fault, basically as a cheap diagnosis (Chris was not available for two weeks and I figured I could try this in the meantime).

When it worked but the keyless go function was broken (you couldn't even use the doors) I decided to strip the old one to see how it functioned. After the tear down, I decided to strip the replacement one, it was a gamble but what was I going to lose if I broke it? £47? lol. I wasn't too fussed as I knew I needed to get a new one with the proper functions anyway, but now it's all good so no need.

 

[SteveX]

I don't want this page to disappear into oblivion yet. Although my problem is solved, I would still like to find I formation on the keyless go override feature.

I read an article that suggest the original key should over-ride the keyless go should it malfunction, an obvious assumption, perhaps the primary key is different to the spare key?

I notice that this relates to the DAS 3 system however that comes with a key card.

Does anyone know the differences between the systems? I am surprised no one has been stuck with this issue before, but it is quite a serious issue if keyless go malfunctions for w203, W209 or other Mercedes of a similar age and they find it impossible to turn the engine and ignition system off. It was lucky I have a bit of knowledge when it comes to cars and opted for what I considered to be a safe option (cut the fuel at idle) but still had to let the battery run flat.

I can't believe that I am the only person this will happen to, especially as these models age so it would be good collect information on it for future members to find

I understand the EIS fuse can be pulled, although I am not sure if there will be other consequences to doing this when everything is live.


Cheers.

 

[television]

You can only have one source of priority, if you start with keyless, then it cannot be over ridden by the key, just like once started with the key, you cannot change to keyless. This is all clearly stated in WIS.

To disconnect the battery would do a lot of damage, as the voltage would rise to 18 volts and it could blow many control units., so that's out.

The airbox just unclips and its off, by placing the palm of your hand over the MAF the engine would stop dead. At this stage once stopped the battery could be disconnected and the EIS would return to normal, so no point at all to let the battery run down.

 

[SteveX]

You can only have one source of priority, if you start with keyless, then it cannot be over ridden by the key, just like once started with the key, you cannot change to keyless. This is all clearly stated in WIS.

To disconnect the battery would do a lot of damage, as the voltage would rise to 18 volts and it could blow many control units., so that's out.

The airbox just unclips and its off, by placing the palm of your hand over the MAF the engine would stop dead. At this stage once stopped the battery could be disconnected and the EIS would return to normal, so no point at all to let the battery run down.

But when you stop the engine the ignition is still at position 2 effectively with keyless, so there is still a lot active in the car at that point in time, surely it's not a good idea to disconnect the battery even when it is at this point.

 

[television]

Not much different to just turning off in many ways. you can turn every thing off in the car, The only other way is to pull the EIS fuse if it is totally dead when the fuse is pulled.

 

[SteveX]

I ended up fitting another, although the other one worked it came out of an older vehicle and looked a bit more tatty, so I ended up buying one for £100 from a 2008 CLK and fitting it (with retrofitting keyless go). The interior parts have much newer part numbers, and it came from a Merc Indi who did a star check on the car it came from so it also has a guarantee. Looked like new inside.

All working and nicely done Happier now it has newer parts fitted. Total cost to repair and diagnose myself £150, although I am going to flog the two shifter covers on ebay to offset the cost of the first so £100 all in I call a good job