1997 Ford windstar blower was stuck in defrost mode unhooked the rear vacum switch and it would come out the vents but I left it unhooked now I have no ac in the front do I need to fix the Problem in the back before the ac will work or what should I do thanks.

are you trying to get heater working or A/C or just heater + defrost mode ( no whether there told)
well the HVAC is failing
it needs service.
the service manual covers this chapter HVAC.
The vent actuators can fail all these way.
fuses all good.
motor blower does spin fast, does it hear and felt on one of many vents. in recirc mode is best.
if blower is dead , or silent the blower on HIGH (is it)
on high the resistor block is BYPASSed.
the blower resistor block is bad or blower dead.
next mode motors (actuators)
causes aplenty
1: fuses blown. easy 20cent fix. fuse 17?
2: damper shaft jammed. (we hand turn it ,proved)
3: motor on shaft dead bad. (mode dead?)
4: controls to motor dampers bad.


1997
Mode control motor
Recirculation control motor
and blend motor, all; air mixture motor

the control panel as 5 switches for mode.
and 5 wires and 1 ground
we'd test all 5 modes to be sure the motor went to all 5 modes (eyes on motor)
if not, we'd turn pull mode motor make sure the modes an all be tuned by hand.
then if yes a news motor is needed.
the logic for the controller only shows each 5 grounds the line for proper mode.
the LED there can lie due to each mode switch has 2 switches for each mode. 10 total.
if some modes work , the ground is good.g402

This is caused by a low engine vacuum, the engine vacuum is low when you accelerate, the HVAC system loses vacuum to the mode control vacuum switch and defaults to the defrost ducts for safety. You likely have a leaking mode control vacuum switch in the control panel of the heater AC system (HVAC).

this is usually controlled by vacum look for a broken or leeking vacum line

The air direction is vacum controlled. If you have 4X4 and ESOF ( switch in the cab) then you need to inspect the vacum lines that go to the hubs and possibly the hub seals. "default" position for air flow is the defrost position. If you DON'T have 4X4, and it's a diesel engine, inspect the vacum pump, If it's a gas engine then look at all the vacum lines from the intake manifold for a leak.

POSSIBLE VACUME LEAK,UNDER THE HOOD,BROKEN VACUME CANISTER ,STUCK BLEM DOOR

What is the solution for window not working?

THIS SYSTEM HAS NO VACUUM CONTROL IT IS DONE WITH ELECTRIC MOTORS I KNOW FOR THE BLEND FOR HEAT/COLD SETTING IF YOU REMOVE THE RADIO AND BEZEL IN CENTER OF DASH YOU CAN LOOK IN AND SEE THE ELECTIC MOTOR WHEN THESE GO BAD YOU WILL GENERALLY HEAR A CLICKING SOUND WHENEVER A CHANGE IS MADE ON DASH UNIT LIKE TURNING IT FROM HOT TO COLD NEVER HAD ISSUE WITH VENT CONTROL MAY USE SAME STYLE MOTOR HOWEVER IF IT USES VACUUM IT IS SUPPLIED FROM PORT ON REAR OF UPPER INTAKE PLENUM TOWARDS PASSENGER SIDE SEVERAL VACUUM LINES CONNECT THERE ON A 3.8 V6 WHICH I ASSUME YOU HAVE HOPE THIS HELPS IF NOT CONTACT ME @ FIXYA

Hello.Yes,it is a vacume problem.What happens is that the vacume controled a/c control head looses engine vacume because the one-way vacume valve fails.This valve is located near the firewall.Follow the vacume tube coming out of the evaporator housing in the engine compartment.

vacum leak in supply line

both of you all prob have problems with the flappers or baffles in the rear that controls the air flow they may just need to be moved manualy becase somthing is stuck in there or the could be broken.