1988 model XJ40, with heater control set for heat we get heat from dash vents but cold air from under dash outlets. Both fans are functioning. We also have heat when set for defrost. I have a replacement electronic control unit to install but this seems to be vent control issue?

 

The distribution flap servos are on the right side of the climate control heat exchanger box. They both need to operate and it sounds like the lower one is 'stuck'.

Sometimes you can tap on it with a dowel to get it moving again.
Sometimes it just needs to be replaced.

You need to do a forum search for 'climate control servo motor' or something like that.

bob gauff

 

Yeah, I got the flaps unstuck on my former '94 a couple of times by rapping on the blower housing with a wrench. You have to take off the passenger knee bolster to do it. Probably not a 'forever fix'…

Scott

 

Hi Buegs,

Below are links to photo-tutorials that will tell you more than you ever wanted to know about the vent gearmotors Bob and Scott mention. The photos are of our '93, but I believe yours will be similar. The photos at the first link show how to remove the knee bolster in case you've never done it before. Yours may be slightly different but the principle will be the same:

http://www.jag-lovers.org/snaps/snap...?id=1390243091

Welcome to Jag-lovers - Members Photo Viewing Page
Welcome to Jag-lovers - Members Photo Viewing Page
Welcome to Jag-lovers - Members Photo Viewing Page
Welcome to Jag-lovers - Members Photo Viewing Page
Welcome to Jag-lovers - Members Photo Viewing Page


Cheers,

Don