Defrost lever (red) does not engage

[jgurnari]

The defrost lever cable must have come off. When I slide it does not engage the defrost vent... I can see in the trunk on the passenger side it does not move. But if I pull in the cable in the trunk and the driver side the vent move is the passenger side... again, it does not engage using the red lever on dash. How can I get to the cable under the dash? Or am I looking in the wrong place?
Thanks
85 911

[Hi_Fi_Guy]

Typically the way the cables are attached to the dash levers it would be nearly impossible for the cable to come detached from the lever. So definitely check the connections in the front trunk first and check the big rubber grommet where they pass through to the underside of the dashboard.

From under the dash you can check the grommet again where it enters the interior. The cables run along the under dash area to the ventilation controls.

The controls are connected to a support under the dash by 1 bolt if memory serves. You can loosen the controls enough to slide them out of the dash 3-5 inches and see if all the levers and cables are connected and working.

IF you need to remove the entire unit it is possible but gets more complicated. Easier to fix with cables and controls in-car if possible.

[jgurnari]

noticed that the cable Arc’s When I move the lever, which shows that it is obviously connected at the controller, therefore the cable is not sliding within the outer housing (cover), it does slide if I hold the cable in place and move the lever ... how can I lubricant it so as to have it slide easily? Or should I tie the cable down so it won’t arc?

[Hi_Fi_Guy]

Sounds like the flapper may be sticking or stuck. Try this test.

- Disconnect the clip and screw that holds the cable onto the plenum in the front trunk.
- Try moving the red slider control on the dash. Does the cable move in/out as it should?

- With the cable still disconnected used your fingers to move the flapper by pushing and pulling the pin where the cable normally connects. Does it move easily or does it feel stuck?

The test above will definitely tell you if the problem is the cable or the flapper (unless neither work).

If the flapper is the issue there are threads here describing how to disassemble, clean, lube, and reinstall the ventilation system.

If the cable is the issue it should be possible to lubricate it using one of those clamp on cable lube tools made for motorcycles. There are versions that can work with the cable in place and some that are only made to work with the cable removed.

Cable Luber
https://www.motionpro.com/product/08-0182

[creaturecat]

if the cable is broken at the controller end, you gotta go deep.
they didn't make it easy ..........

[jgurnari]

HI_fi_guy

Without having to disconnect the clip and screw, I can easily move the flapper... the defrost lever will not move the cable unless I hold down the cable at the driver side in the trunk. If I move the lever the cable just arc’s due to cable not sliding through it’s housing.(outer covering). It’s definitely not the flapper. When I move the cable manually at the flapper I can see the cable arc at the driver side in trunk and the red lever does not move. I will
Post a video of what’s happening

[Mike Andrew]

Had a similar issue with my fan control. I did what HiFi Guy suggested above - removed frunk end of cable, used a cable lube device and then used my compressor and blew air into the cable. Repeated twice and it now works flawlessly, smooth and no cable arcing from binding in the sheath.

Good luck.

[jgurnari]

Thanks everyone. I’ll try pushing through with lube and high pressure