climate control
 

Hi guys,
i recently change my blower control module.
Now the problem with the fan Always on is fixed.


I have a new little (i hope) problem with the climate control.
if i push on the botton for change air flow the light on the botton came on, but the flow don't change, it's seems that is block in defrost position.


Did anyone have the same problem?
What can i check?
Thanks in advance
Max

Re: climate control
 

I had a similar problem. In my 1994, the problem was a restriction of the vacuum tubing that operates the air flow dampers. What year is your car? Are you familiar with removing the passenger side hush panel (above the passenger,s knees? Do you have a way to test vacuum in the HVAC system?

I am on the road. I will try to keep up with your posts.

Jim

Re: climate control
 

Hi Jim,
I have a 1990 zr1, but this problem is on a 1990 l98, i think the climate control is the same.
Sure, i have done a lot of work on my car, but i havent a vacuum tester, and i dont know what is HVAC system...
Thanks for the helps!

Re: climate control
 

HVAC = Heating, Ventilation, & Air Conditioning. The dampers that control the air flow in the ventilation system are operated by vacuum with the engine as the vacuum source. The exception to this is the flapper that controls air temperature by adjusting the heated and cooled air supplies.
That damper is controlled by a motor.


The damper that controls the air flow to the windshield defroster is directly under the defroster grill in the center of the dash. If you remove the defroster grill piece, you can look through the windshield and see the damper. With the engine running, and the temperature control set to lower than the air temperature in the car, the damper should move to direct the air flow to the AC outlets in the dash. Then switch the Climate Control to Defroster. You should see the damper move.


Do you have a Service Manual for the 1990 Corvette?


Jim

Re: climate control
 

Hi Jim,
Thanks for all the information, I think I'm just a little stupid!!!when I change the blower control module I try the climate control with the engine off and the car was sitting for about 5/6 days...in this weekend I try to turn.on.the engine and control the air flow....
I'll let you know!!!
Yes I have a service manual for 1990

Re: climate control
 

Don't feel too bad.
I have seen many a tech after putting it all back together get fooled for a moment, forget, and do the same thing.
The defrost air flow is the default in the event of vacuum loss, I suspect for safety to keep the windshield clear to see rather than keep the occupants comfy.
As the above post stated, airflow diversion is vacuum controlled upon instruction from the control head and programmer. Most common problem is a deteriorated or rodent chewed vacuum hose. The above post on how to observe the operation from above is a real time-saver!!!
Hopefully all will be fine once you start it up!
Marty

Re: climate control
 

Hi guys...today I check the air condition with engine run.
It work perfectly!!!
Thanks for helps!!!
Max