Daniel Melusky

i have this 2001 e430 and its trunk won't open. the physical key and button won't open it. i did a vacuum test and its leaking so i bypassed the head rest and that solved that but it won't open. i tried a new vacuum pump nothing changed. the only code in the car is in the lower control panel it says "control module does not match vehicle model. i tired another switch pack but it was from a 98. both work perfect except the trunk won't open. I can't get the code to go away. I plug the vacuum line into the door lock hole and hit unlock the trunk opens right up. I'm at a loss. Is there something i missed? no fuses are blown i checked all of them is there a relay i should replace? I don't have access to a newer switch pack i thought they were all the same except for wagons. any advice?

Plutoe

Happens all the time on older MB when the metal key won't open the trunk----your only recourse now is to have the lock drilled out, purchase a new set.

nikono

Don't drill out the lock!!!
When using door vacuum line, trunk can be opened, that means the electrical power is lost to open the trunk when pushing trunk button on remote control or trunk switch at center console.
There's a switch as shown in picture at the bottom of trunk lid. Remove the lining, you will see that the wire plugged to the switch dropped out. The reason was each time the trunk is slammed closed, the impact shook loose the contact a little bit then one day, the wire completely fell off. The system thinks the trunk is already open.
It's tight space, long nose pliers to grip the wire to plug it back to the switch will fix the problem.
To make sure it won't happen again, squeeze the plug a little to make it tight.

raymond g-

hmm, all along, I thought that white plastic plunger only served to toggle off/on
the trunk light...no more and no less. I didn't realize that it is part of the trunk
locking mechanism system. you sure about that?

shadenfroh

Drilling out the lock won't solve a vacuum/electrical problem

Do you know the correct way to open the trunk with the metal key? Put key in, rotate key, keep key in rotated position and push button in.
When the trunk is closed does the light on the button on the console go out?
When the trunk is closed and you try to open it do you hear the pump working?
You found a vacuum leak - what's leaking?
You bypassed the head rests which solved "that" - what is "that" if the trunk still won't open? What do you mean by bypass?

The vacuum system is pretty simple so you should be able to get help, but only if you provide enough info


Raymond, the information is correct - when that switch is not pushed in (trunk is open/plastic trunk liner is removed), the vacuum pump doesn't activate since the car thinks the trunk is already open. By the way, an interesting feature is the ability to pull the switch out until it clicks - that turns off the light for any event when you want to leave the trunk open for an extended period of time.

raymond g-

shadenfroh - well, I must have some alien model then because my 1999 E320
doesn't function that way. the trunk release operates regardless of the position
of the pin switch (in, out, outtest)...which only serves to activate the trunk light.
I tried it several times just now, using various permutations of the pin switch

nikono

I had the problem, fixed it a few years back, took some pictures but they're too hard to be found in my 50,000-photo archive. LOL.
The OP can remove the push pins on the left of the trunk lid to partly lift the lining to peek to see the loose wire with a flashlight. Don't try removing the switch. As I recall, it'd be very hard to put the switch back in.
To really push the loose wire back in with a pair of long nose pliers, he also needs to loosen the lock screws to get the lining out to have more room to work because the lock sits right on the lining. Make sure to mark the lock, screws with permanent marker to ensure proper lock seating when putting everything back.

GreggT

I'd try this before giving up or drilling out locks........disconnected fuses & battery….reconnect. It is always possible that the trunk lock actuator is actually stuck or pushing in the unlock position but the latch not releasing. Disconnecting power allowed the actuator to relax & reset.