assman300

Hello everyone,, Im new to mercedes, and therefor the forum,,

I just picked up my car today and have a couple issues. I was wondering if anyone here had any info they could send my way...

1) the light behind the 2 right vent controls is out. whats involved in changing that bulb?

2) the warning for an exterior bulb out comes on every now and then,, but i didnt notice any bulbs out.. if i shut the car off and restart it,, it will be gone,, but after a while it might come back.. ??

3) when i push the trunk release on the remote or on the dash, it doesent pop open, only way to do it is to push the key hole in the back

4) apparantly theres a way to make the windows and roof open with the remote... mine doesent seem to do that??


thank a lot,, any infor is greatly appreciated..

Mike

S-Clusiv

Welcome...well about the trunk release, you're hitting the unlock button twice and still nothing?

And on my 1995 S600, you had to align the remote with one of the recievers on the door handle and press and hold the button down.

(assuming the '95 and '99 had the same key design, lock and unlock share the same button, correct?)

assman300

Hello, Thank you very much for you reply...

No the lock and unlock are 2 different buttons,,, and yes, i can push it as many times as i like,, it seems like the actuator to release the trunk isnt engaging,,

Now someone told me that they just need to be adjusted,, because my first thought was the actuator stopped working.... im wondering what needs to be adjusted.. or if there even is anything to adjust

jjay911

the irony is I have all the same issues with my car....

I~LUV~W140s

First of all, the light behind my two right vent controls is out also. What's involved with replacing that? And I don't think the keyfob will open the windows and roof, but I know that if I hold down the lock button, with the fob pointed directly at the reciever, it'll put them up automatically.

wbrian63

First - please post your year and model of 140 when asking a question. There are subtle differences between the years in these cars - makes the q&a process easier and more accurate.

Vent control bulb no big deal. Open the glove box and there's a small piece of trim on the end of the wood strip that covers the wheels. I'm pretty sure that just pops off. You'll see a screw behind the trim, remove it. Then gently pry the wood trim away from the dash. It has a couple of bullet-catches in the middle, and I think a clip on the left-hand side - but the screw is the only hard attachment point.

That should reveal the bulbs - get one as a sample to show the MB dealer - not available at your local parts store.

The CF (convenience feature) module is supposed to allow opening the windows (not the roof) by holding down the arm/disarm button (if a single-button remote) or disarm (if a multi-button remote). On cars with the RF/Infrared system (95+), this feature only works with the Infrared side of the system - i.e. line-of-site to the car - supposedly max 10meters.

My system has worked sporadically, most recently not at all. I don't have much need for this feature, so I don't wallow in its failure. But it is supposed to work - but remember - only in line of site for the Infrared receiver (either on the doors or beneath the rearview mirror, depending on model year)

Trunk release issues:
First - trunk release will only work if the latch on the trunk hasn't been locked with a key. If you can unlock the car and open the trunk without the key (just by pressing the trunk lock cylinder), then the latch is in the right position. If it still takes the key, the remote release isn't going to open the trunk. Insert the key and turn it to the left (I think) - then turn it back to vertical and remove the key.
If the trunk release works with just a push of the lock cylinder, then we need to see if the actuator is working.
The trunk release is pneumatic - when you push the button on the dash, do you hear a pump running under the passenger rear seat? The button on the dash will most likely only work when the car is in park. Turn the key to position 2 (all dash lights on), but don't start the car. Turn the radio off and close all the doors. Press the button - you should hear the pump run briefly. If you don't, find the fuses for that system (it's in the trunk fuse box) - I think fuses 11 and 3 are the ones you want. Pull them for 60 seconds and replace - retest. I'm pretty sure the system is smart enough to "timeout" a circuit that has repeated failures. If the release actuator is defective, it will require too much air pressure, and the system will time it out after a while.
If you hear the pump run, then next step is to listen for hissing inside the trunk when you try the same test. Open the trunk and do the following:
On the inside of the trunk threshold, you should see a lever - lift that up until it clicks - the grab handle should retract at this point. Now, with a screwdriver or some other device, trip the trunk latch bail in the threshold - it looks like an upward pointing "U" - it pivots and should click into position. Now have someone push the button on the dash and listen for a hissing noise - that will indicate the pump is trying to activate the latch.

I'm not sure that tripping the bail is required, but we need to be for sure that the car thinks the trunk is really closed.

BE SURE TO PRESS THE TRUNK LOCK BUTTON TO RELEASE THE BAIL BEFORE ATTEMPTING TO CLOSE THE TRUNK.

If you don't hear a hiss, possibly the switching valve is the culprit. On earlier 140's there's a valve mounted behind the valance on the passenger side of the trunk. (This might be true of later models, but I don't know for sure) The circuit that opens the trunk is "teed" off of the circuit that unlocks the gas cap door. Without this valve, every time you unlock the car, you'd also unlock the trunk. When the trunk is to be opened, the same circuit is activated, but this time, the valve between the trunk lock actuator and the circuit is opened to allow the pressure to flow. If it's not opening, then the pressure can't get to the actuator. You can test the valve by attempting the test again, probing the non-brown wire (all MB ground wires are brown, don't know what the actual trigger wire color will be, but there should only be 2 wires) with a test lamp - you should get 12v+ to the valve when it's supposed to open.

If you've got voltage to the valve, possibly the valve is defective. With a 7 mm wrench, you can disengage the pressure lines. You can try to bypass the valve with a short section of small vacuum hose to see if the latch will release.

Hope this helps.

Warning for bulb out - isolate it to when it comes on:
When you turn the parking lamps on - one of the bulbs in that circuit. This includes the license plate lamps.
When you step on the brake - add the high-mount stoplight to the list.
Turn signals usually are obvious, as the flasher "flashes fast".
This system is really picky about the bulbs that are installed. I had constant problems with false reports on my system until I broke down and purchased new bulbs for every circuit from MB. If any of your lamps has a brass-colored base, it's not an MB bulb.
The high-mount stoplight is also a halogen bulb - mine had been replaced with a non-halogen unit - this caused sporadic reports from the system as well.

Welcome to the wonderful world of 140's.