W203 boot won't open

[MisterMicawber]

The boot won't open on my w203 2001 C220. Is there anyone who can help me assess what's going on?

Yesterday I went to open the boot, using the handle on the boot in the usual way. The usual whirring sound happened (sounds like an electric motor) but the click that usually follows didn't happen and the boot stayed firmly shut. I think there's some sort of release mechanism from the handle down to the latch at the edge of the boot lid and I suspect that might have failed.

So then I tried to open the boot with the key. This was very stiff - probably hadn't been turned for 10 years - but I managed to turn it 90 degrees anti-clockwise. At that point, there was a kind of click or resistance and it would move no further. However, it would also not move back to its original position. And the boot still didn't open.

With the lock in the new position, the boot lock handle, the key fob and the driver's door switch no longer have any effect - ie there's now no whirring sound coming from the lock.

I've tried lots of WD40 and jiggling of the lock with the key but the lock stays stuck in the new position. Feels as though the levers have engaged, leaving a bit of room to jiggle slightly back and forth but it won't turn back to the original position.

I've tried both keys and both work fine on the driver's door but neither will turn the boot lock, though they both insert ok. I'm fairly certain the key matches the lock because it turned 90 degrees before getting stuck in the new position.

What I'd like to know, if anyone can help, are some details of how the key is supposed to work (apart from opening the boot, of course!)

1. Does it turn off the circuitry to the remote boot unlocking? Is this why I no longer hear the whirring sound.

2. What are the lock's possible positions? On the driver's door the slit for the key is vertical. You can turn it 90 degrees from the vertical position anticlockwise to unlock the door (to 9 o'clock position) and 90 degrees clockwise from vertical to lock (to 3 o'clock position). But its normal position is vertical, though I can't remember whether it springs back to this position.
Is this the same for the boot lock?

3. Do the symptoms suggest that the lock levers have got stuck and are stopping the key from turning back to the "vertical" position?

I've looked for a diagram on the internet but without success. Dec provided some very useful pictures of a w202 boot lock. But I haven't found anything specific to the W203. Hope someone can help.

 

[MisterMicawber]

Anyone with an early W203? Info wanted.

I wonder if there's anyone who's got an early W203 (mine's from 2001) who could spare a couple of minutes to look at the manual boot lock.

What I'd like to know is which direction the key is supposed to turn to unlock the boot. Does it turn anti-clockwise to unlock?

Does it turn clockwise at all from the vertical position?

And when the key is turned 90 degrees anticlockwise, does this disable the electrical circuits so that nothing happens when you press the normal boot unlock handle?

If anyone could spare a couple of minutes to look at this, it would be much appreciated. Many thanks.

 

[umblecumbuz]

Checking with my own W203 instructions (later model - 2004), the boot is unlocked manually by inserting the key and turning anti-clockwise one quarter of a turn.

A tip I read on this forum to get a lock working if it has not been manually used for some time is to liberally oil it (WD40) and then hold the side of an electric grinder or drill against the lock, so that the vibrations from the grinder/drill help to shift the pawls inside the mechanism.

It does sound, though, as if you have a broken internal mechanism, in which case the above info will not help. Worth a try though.
Baz

 

[MisterMicawber]

Many thanks...

Many thanks for checking!

I've tried loads of WD40 but I'm beginning to wonder if I'm wasting my time. My lock turned 90 degrees (a quarter turn) anti-clockwise and then stopped. And it won't turn back. So I'm now wondering if this is the correct behaviour of the lock - it turns but won't turn back until you close the boot again.

But of course my boot hasn't opened so I can't reclose it. Is this guess right? Does the lock stay in the quarter turn anticlockwise position until you close the boot again? Or can you turn it back to its normal position with the key?

I'm beginning to think that if there's only one link from both the manual lock and the electric opening handle down to the latch at the rim of the boot, then if this link is broken, neither the electric opening mechanism nor the manual key-operated lock is going to work. If that's the case, the key only serves as a backup when the electrical system isn't working (flat battery, failed remote keyfob etc.) but the key doesn't serve as a backup if the link to the latch breaks.

Hope you can help just to let me know if you can turn the key back to its normal position or whether it only springs back when you close the boot.

 

[umblecumbuz]

Ah ... there lies a problem. My car is the estate version, which does not have an external key slot, so I can't advise. I got the info on the lock from my manual, but it does not cover whether or not the lock returns to 'upright' when you reclose the boot.

There are plenty of forum members with more experience, and I am sure one will be along with a solution soon.
Baz

 

[Xtractorfan]

On my S class I had a similar problem after a flat battery, but I always have oiled my lock every few months, but it has to be held in the 90 deg position and the button operated to open the boot lid...and it has to be fully turned the full 90 deg,
There is a post on here somewhere about a boot opening procedure, I shall search for it.. maybe some of the other guys will try as well..
Just type 'boot lid opening' in the search box on the top tool bar and see what comes up..

 

[Dec]

If you have a First Aid on the parcle shelf you could try plan B in post #35 here… Edit;see post #10 below


Dec

 

[MisterMicawber]

Dec, Many thanks for the link. On my browser it doesn't seem to go to the right place. It looks as though it has dots in the middle of the address. Could you check? If you select and copy it from the address line you should get the whole address.

I'd also like to thank you for all the pictures you put up on another thread some time ago of the dismantling of a w202 boot lock. That was very helpful, even though there are obviously some important differences in the w203.

 

[MisterMicawber]

Boot lid diagram

Just type 'boot lid opening' in the search box on the top tool bar and see what comes up..

Xtractorfan, thanks for the suggestion. I'd been using different search terms. Using this search I came up with this page http://forums.mercedesclub.org.uk/showthread.php?t=84751

Here there's a detailed diagram of the CLK boot lid and it looks as though it may be similar to the C class W203. In particular, the lock assembly is at the "top" of the lid and the latch is on the rim. They're linked by a cable, labelled part number 10.

(Later edit: this is bizarre. The diagram has now disappeared from the post by Television. The post says, "Here is the diagram," and previously there was a large image of the boot layout just below. Let's hope it comes back. Another later edit: now the diagram is back.)

This seems to suggest that if the cable linkage fails, you won't be able to open the boot either with the remote electrical mechanism or with the manual key.

Does anyone know where diagrams like this are available? If I could find one for the W203 it might confirm whether I'm wasting my time trying to open the boot with the key.

 

[Dec]

Dec, Many thanks for the link. On my browser it doesn't seem to go to the right place. It looks as though it has dots in the middle of the address. Could you check?

/
Sorry about that, should have double checked.
This may or may not be useful, Plan B, post #35 here… http://forums.mercedesclub.org.uk/showthread.php?t=73958&page=4

Dec

 

[MisterMicawber]

/
Sorry about that, should have double checked.
This may or may not be useful, Plan B, post #35 here… http://forums.mercedesclub.org.uk/showthread.php?t=73958&page=4

Dec

Thanks for that. Very useful pictures. What I'm not sure is whether it's going to look the same on a W203. Also wondering if access would be easier with the seat back taken out than via the first aid kit. (Haven't actually tried to look yet, though I've seen a diagram of how you take the seat back out.)

Before I go down this road, I wanted to be clear about whether there's any chance that the key will open the boot if I keep trying. But if it's linked to the latch by a broken cable, that's never going to work. So I'm still hoping someone with an early W203 can confirm whether the key will move back to the normal position after you've turned it a quarter turn or whether reclosing the boot resets the key position. That's to say, has my key worked correctly or is there a problem with the manual lock rather than a broken cable?

 

[Silver_Star]

Had something similar on mine (saloon). Pulled the relese on the boot and nothing happened.

I got round it by pressing down on the boot from above (ie trying to shut it a bit further) then pulling the release and it opened.

When it's open lube the lock up with oil or PTFE.

 

[Dec]

In modern cars the key blade is for emergency entry only as its never used in place of the remote, because of infrequent use, the are prone to seizure, it should be fool proof and be capable of opening in the event of electrical and mechanical failure, that’s the whole point but the reality seems to be different.

All you can do is try with the key, or as Dan suggests above, if you can access the boot by removing the back of the seat, if that’s possible? and you have those 2 bolts then that will make life much easier.

Dec

 

[MisterMicawber]

Had something similar on mine (saloon). Pulled the relese on the boot and nothing happened.

I got round it by pressing down on the boot from above (ie trying to shut it a bit further) then pulling the release and it opened.

When it's open lube the lock up with oil or PTFE.

My problem is that after I turned the key a quarter turn, the key stayed in that position and the electric mechanism no longer worked.

I'm suspecting that this may be correct behaviour of the lock (apart from the boot staying shut!) But if you have the same model, I wonder if you might find five minutes some time to test it. When you turn the key a quarter turn, does the handle release no longer work? (ie electric circuit turned off.)

And does the manual lock stay in the quarter turned position? Perhaps until you close the boot again?

Hope you might find a couple of minutes to check this for me.

 

[Silver_Star]

No problem, leave it with me and I will report back when I have finished work.

 

[MisterMicawber]

No problem, leave it with me and I will report back when I have finished work.

Many thanks. Much appreciated.

 

[anyweb]

i've a W203 from 2000 so i went outside and checked the boot key,

looking down at the boot lid with the key in place turning it to the anticlockwise LEFT seems to leave the key in that position and i believe this is the LOCKED position

turning the key RIGHT 180 degrees from the position above (or 90 degrees from normal) in a clockwise direction produces a click and you can then use the lever to open the boot,

just tried it ! and my boot opened and then my car alarm went off ;-)

hope that helps you with your boot

 

[adie596]

Boot lock

I have a 2001 w203 and confirm that turning 90 degs to the left locks the boot. Turning a furthur 180 degrees from the locked position opens the boot but you have to apply pressure to the opening handle at the same time. The key position moves 90 degs to the left or right irrespective of wether or not you open the boot lid. It sounds like yours has stuck in the locked position.

 

[MisterMicawber]

turning the key RIGHT 180 degrees from the position above (or 90 degrees from normal) in a clockwise direction produces a click and you can then use the lever to open the boot,

Many thanks for checking.

Are you saying that turning the key by itself does not open the boot? You have to use the release handle, too?

And when you then use the release handle, does it use the electrical mechanism to open the boot? Or is there some mechanical link which takes over and allows you to use the release handle in this way, too?

 

[MisterMicawber]

I have a 2001 w203 and confirm that turning 90 degs to the left locks the boot. Turning a furthur 180 degrees from the locked position opens the boot but you have to apply pressure to the opening handle at the same time. The key position moves 90 degs to the left or right irrespective of wether or not you open the boot lid. It sounds like yours has stuck in the locked position.

That's a great help. Didn't see your message while I was doing my last post.

That being the case, it sounds as though more WD40 and jiggling the lock may be worth the effort.

Can I just clarify one more point? You say you have to apply pressure to the opening handle, too. Do you have any impression of whether you have to turn the key first and then operate the handle, or do you operate the handle first and then turn the key? Is it possible my key is not turning because I haven't used the handle at the same time?