dash "grill" leaking cold air- how to fix?

[Russell]

I just noticed that cold air is “leaking” through the grill on top of the dash although all outside air vents are closed. The grill rotary knob is in the off position. The middle slider control for outside fresh air is positioned to left in the off position. The center dash vents and door fresh air vents are closed. The temperature control between the center dash vents is on full warm.

Cold should not be leaking into the car in this situation. After reviewing the TIS and ETK, It seems there may be an issue with one or more of the stepper motors that control the fresh air flaps.

Any thoughts? This looks like a tedious job to get into this area to adjust, replace or in general repair.

TIA

[shogun]

I only find pics from the E32, but it should be similar. Check the stepper motors first. Sometimes they brake off.
http://shrubbery.student.utwente.nl/johan/center_vents/broken_bits.jpg
cold air from center vents (http://shrubbery.student.utwente.nl/johan/center_vents/center_vents_v1.1-1.html)

[Russell]

I get warm/cool air out the center vents depending on the temperature and thumb wheel settings. It is just the cold air leakage through the dash top grill that I do not want. I am going to remove the grill and see what is down there. Perhaps I can just cover the opening(s) in the cold air duct under the griill??? I never use the grill for air distribution.

Thanks for the links and advice. I also going to read up on how the system works.




I only find pics from the E32, but it should be similar. Check the stepper motors first. Sometimes they brake off.
http://shrubbery.student.utwente.nl/johan/center_vents/broken_bits.jpg
cold air from center vents (http://shrubbery.student.utwente.nl/johan/center_vents/center_vents_v1.1-1.html)

[Russell]

Anyone know how the "grill" and thumbwheel that controls opening and closing the grill works?. It appears to be a mechanical connection without stepper motors. If I can make it close completely, there would be no air leak,

As aways, TIA




I just noticed that cold air is “leaking” through the grill on top of the dash although all outside air vents are closed. The grill rotary knob is in the off position. The middle slider control for outside fresh air is positioned to left in the off position. The center dash vents and door fresh air vents are closed. The temperature control between the center dash vents is on full warm.

Cold should not be leaking into the car in this situation. After reviewing the TIS and ETK, It seems there may be an issue with one or more of the stepper motors that control the fresh air flaps.

Any thoughts? This looks like a tedious job to get into this area to adjust, replace or in general repair.

TIA

[Russell]

I removed the dash top grill. Two small screws and it pops out. The problem was apparent as the foam gaskets around the grill duct that fits into fresh air ductwork had deteriorated and began to crumble. I plan to replace them with the adhesive backed weather-stripping and/or some other sealing material. This should take care of this issue.

Through the TIS and ETK and learned a bit about how complicated the climate system is on these cars. IMO, it does not needed to be. Climate control on both side of the car has little appeal to me. Can you imagine the 4 zone systems available on some Mercedes models. :(


I just noticed that cold air is “leaking” through the grill on top of the dash although all outside air vents are closed. The grill rotary knob is in the off position. The middle slider control for outside fresh air is positioned to left in the off position. The center dash vents and door fresh air vents are closed. The temperature control between the center dash vents is on full warm.

Cold should not be leaking into the car in this situation. After reviewing the TIS and ETK, It seems there may be an issue with one or more of the stepper motors that control the fresh air flaps.

Any thoughts? This looks like a tedious job to get into this area to adjust, replace or in general repair.

TIA