How to remove dash vents in 124 models (1986 to 1992)
by George Murphy, Technical Committee Chairman, Director at Large
LEFT & RIGHT VENTS: There are four spring clips that secure the vent to the dash. They are located inside the vent louver assembly. Using a flashlight, look inside the vent at the lower and upper surfaces - you'll see spring clips with a small hole just protruding above the surface of the vent - 2 on the bottom and 2 on the top. The trick is to use a small pointed tool inserted into the hole in the clip. Lift the clip upward (or downward for the upper ones) while applying an outward pulling force on the assembly - I use needle nose pliers padded with a cloth on the jaws so as not to mar the vent vanes. Don't pry against the dash - it's soft and can be torn or dented. Just maintain an outward pull on the assembly while you lift each spring clip in turn - the vent assembly will ease on out. It is then a simple matter to unplug the illumination bulb and replace it. DO NOT USE MORE THAN 0.4 WATT BULBS - the excess heat will distort the plastic bulb holder and make it impossible to ever get the bulb and socket out again. The correct bulb is part no. 000 825 00 99 - a tiny push-in type bulb with gray plastic sleeve and straight contacts. The bulb wattage is marked on the gray sleeve.
CENTER OUTLET: In this case, first release the operating lever inside the vent using a metric Allen wrench (about 2 or 3 mm) to unscrew the flap link from the wheel. Shine a light inside the vent along the right side of the wheel - the Allen screw is visible inside - unscrew (turn counter-clockwise) the screw to release the link. On the right side, there is a Phillips-head screw accessible when the glove box door is open. As above, look inside for spring clips to retract that will allow the assembly to move outward. Use same size bulb as above. When re-assembling, after the unit is seated, re-attach the wheel link to the flap lever by engaging the Allen screw and rotating it clockwise. Tighten the screw only enough so that the wheel closes the vent with slight resistance. (If you overtighten it, you get to buy a new assembly...)
All technical advice is presented as a courtesy and service of the Mercedes-Benz Club of America, which does not guarantee the suitability of use of the advice, which is at your discretion.
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