W220 S500 Boot Lid (another one, sorry!)

[SeasidePete]

Hello all, sorry to do this but I have a boot lid issue to add to the list!

My car is a 2003 W220 S500. My issue is the boot lid. The button on drivers door, the key fob and the button on the boot itself will not open the boot (this is not a self opening/closing version BTW) The only way to open the boot is with the key.

• Vacuum system for other door locks works fine
• Fuses not blown
• Hocky Puck type bladder thing is not cracked or split (that I can see) and I can't feel any air escaping anywhere when operated.
• The silver boot Iid grip sticks out perminantly
• With the boot lid closed and my ear to it, I can hear things whirling and hissing when I hold down the boot opening button on the key but boot will not open.
• With the boot lid open, I can manually push the locking hook into the closed position (the thing that hooks around the locking bar bit above the bumper) and then when I press unlock on the key, the locking hook releases so I don't think the issue is the vacuum.
• I also note that with the boot lid open, I cannot see any parts moving on the mechanism the boot lid grip retracts into. It's worth noting that the bood lid grip has always stuck out since I bought the vehicle but the opening issue has only just started.

Could the issue be the piece the boot lid grip retracts into? Anyone had similar to above please?

 

[SeasidePete]

And does anyone know what this bit is for? The part that plugs into the socket has a microswitch on it.

View media item 8267

 

[SeasidePete]

Problem SOLVED! Having read tonnes of posts on many many forums in an effort to resolve my issue I have now fixed it.

My problem required a number of fixes which I will attempt to detail as best I can. You can read above my list of symptoms but basically the boot would not open with any other means but manually with the key and the grab handle would not reset itself when the boot lid was closed.

After dismantling all the opening/closing and locking mechanisms and checking all vacuum lines I found my issue however I won't detail how to dismantle here, there are loads of detailed posts on this else where but if anyone wants instructions let me know.

This first problem I tackled was the grab handle not retracting. Once I had the part out and inspected, I could see that the vacuum pump actuator that pushed and pulled the handle out wasn't actually attached to the handle anymore. A small clip that hooked onto the handle was missing. Looking around in the boot I found it! A bit of glue stuck that part back on to the arm that comes out of the pump and the arm was reattached to the handle:

Grab handle actuator

• SeasidePete
• Apr 21, 2019

With this part repaired I tested by closing the boot (ensuring the key was in my pocket first!) but.... Nothing, just a very loud hiss.

I knew this hiss couldn't be from any of the actuators/pumps because I'd already tested all of them with a hand vacuum pump to ensure they all held vacuum. I listed carefully and traced the hiss to the air line that was trunked down the right hand side of the boot lid down to the vacuum control unit found behind the TV tuner on the left side of the boot.

About half way down the trunking I could feel a kink so removed some of the trunking:

Grab handle air line trunking

• SeasidePete
• Apr 21, 2019

Grab handle air line

• SeasidePete
• Apr 21, 2019

Applying a bit of pressure while pressing the unlock button confirmed there was a small hole in this air line because once the hold was closed off, the hissing stopped.

I repaired with mixture of glue and sealant, then wrapped it in insulation tape as tightly as I could:

Grab handle air line fix

• SeasidePete
• Apr 21, 2019

I closed the lid, pressed the lock button and.... It worked! The handle popped back in after about 20sec. Pressing the boot open button on the key fob, on the handle on the boot and the release button in the driver door all opened the boot, grab handle popping out as it should. SUCCESS!!!

I can only guess that 2 things went wrong.

1) The little black piece that attached the grab handle to the pump broke off due to the thread that held the 2 pieces together weakening over time and
2) The air line became dameged due to the boot lid opening too violently, stressing the air line which over time led to breaking point.

Hopefully my problems are solved, although I will look at how to make the boot open more gently in an effort to limit future damage to the airline.

I hope this helps others, the problem seems to be quite common. If I can help at all then great.