Defrost not clearing window
Jetsitter
10-10-2006, 04:23 PM
It was raining and about 39 degrees outside when I went to put on the defrost to clear the windshield. The blower seem to be working and the heater as it was putting out heat on the front of the dash. When I put it on defrost there was hardly any air blowing to the windshield and to the side windows. Yet the blower was cranked to the highest setting. the car is a 98 intrique. Help? Just got a new stator put in.
Jetsitter from Canada
Jetsitter from Canada
panzer dragoon
10-10-2006, 11:16 PM
Is this an auto or manual system:
You just replaced the heater resistors = stator? Or do you mean blower motor?
HVAC System - Manual
The heater-A/C control microprocessor releases electrical signals. The vacuum solenoid module converts electrical signals into vacuum commands. The vacuum commands position the following valves in the air distributor:
Mode valve
A/C-defrost valve
Outside air valves
Vacuum is constantly applied to the module. The module distributes the vacuum to five solenoid-controlled valves on the module. The following actions occur when the heater-A/C control signals the module to change an air distributor valve position:
The solenoid that is associated with the valve energizes.
Vacuum is applied to the appropriate actuator.
I have no idea how much this module costs and you may have a duct jammed or a electrical problem = may not be the vacuum solenoid. AllDataDIY has a trouble chart for this.
You just replaced the heater resistors = stator? Or do you mean blower motor?
HVAC System - Manual
The heater-A/C control microprocessor releases electrical signals. The vacuum solenoid module converts electrical signals into vacuum commands. The vacuum commands position the following valves in the air distributor:
Mode valve
A/C-defrost valve
Outside air valves
Vacuum is constantly applied to the module. The module distributes the vacuum to five solenoid-controlled valves on the module. The following actions occur when the heater-A/C control signals the module to change an air distributor valve position:
The solenoid that is associated with the valve energizes.
Vacuum is applied to the appropriate actuator.
I have no idea how much this module costs and you may have a duct jammed or a electrical problem = may not be the vacuum solenoid. AllDataDIY has a trouble chart for this.
BNaylor
10-10-2006, 11:53 PM
By stator do you mean alternator stator?
A common problem is a total loss or lack of vacuum to the HVAC actuators. The vents will stay stuck and the effect is seen mainly with defrost mode. Since you had some sort of work done check the vacuum line which is accessory vacuum on the backside of the upper intake manifold (UIM). You will see a Y connector with a one way check valve feeding vacuum to the power brakes. Follow the smaller plastic line where it is mounted on the firewall and it will eventually loop over by the right upper strut tower into the main wiring harness that goes into the firewall to the vacuum distribution module under the dash. It passes right by the battery and engine compartment fuse box. You may have a loose connection or a break in the line.
A common problem is a total loss or lack of vacuum to the HVAC actuators. The vents will stay stuck and the effect is seen mainly with defrost mode. Since you had some sort of work done check the vacuum line which is accessory vacuum on the backside of the upper intake manifold (UIM). You will see a Y connector with a one way check valve feeding vacuum to the power brakes. Follow the smaller plastic line where it is mounted on the firewall and it will eventually loop over by the right upper strut tower into the main wiring harness that goes into the firewall to the vacuum distribution module under the dash. It passes right by the battery and engine compartment fuse box. You may have a loose connection or a break in the line.
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