No hot air from defrost vents?

If you need dis-assembly or replacement instructions for any other auto/car part, or you want to ask question related to your car/truck jeep problem then please leave the comment with your details, so I can provide you the required instructions and solutions.


This same problem is noticed in many car models.
It sounds like vacuum is not getting to the vent, heat and A/C controls. Find the vacuum CAN. It may be under the hood on one of the inner fenders. The "one-way" check valve is usually located in the line and close to the CAN, make sure it works properly. The valve could be the one thing that's causing the problem. Trace the lines back to the vacuum block at the intake manifold or fire-wall, and also back to where the line goes thru the fire-wall. Check the CAN for leaks or obvious holes. They used to be just a plain metal CAN, but it could be a plastic ball. Check the lines as you go, for breaks and rub-thru's. Move the controls thru all settings and listen for vent door movement. Worst case is a bad vacuum motor or air flow position selector switch, and/or a faulty Blend Door Actuator. If you have been driving around with the Temperature knob or control set at the same spot for months, move it from fully cold to fully hot several times and wait for the air temperature to change each time. This will help reset the blend door and vacuum control system.Thanks.------------

For Instructions regarding All types of car heater and AC problem repairs,check the list mentioned below:--

All types of Car heater Problem troubleshooting?

http://technoanswers.blogspot.com/2011/11/all-types-of-car-heater-problem.html

Blower only blows warm air ?

http://schematicsdiagram.blogspot.com/2011/11/blower-only-blows-warm-air.html

AC cool air enters only the passenger compartment even with the heat control turn all the way?

http://howtobyme.blogspot.com/2011/11/ac-cool-air-enters-only-passenger.html

Saturn Car Blower motor Only works on High?

http://howtobyme.blogspot.com/2011/11/saturn-car-blower-motor-only-works-on.html

For car AC related and Heater related solutions. You can refer the options mentioned below:---

Car AC Blows Warm Air ?

http://technoanswers.blogspot.com/2011/10/car-ac-blows-warm-air.html

How to test AUTO AC pressure?

http://howtobyme.blogspot.com/2011/10/how-to-test-auto-ac-pressure.html

AUTO Air Conditioning Troubleshooting?

http://technoanswers.blogspot.com/2011/10/auto-air-conditioning-troubleshooting.html

AUTO A/C COOLING PROBLEM?

http://technoanswers.blogspot.com/2011/10/auto-ac-cooling-problem.html

Fixing refrigerant leak?

http://howtobyme.blogspot.com/2011/10/how-to-fix-refrigerant-leak.html

How to locate Car AC Refrigerant leak?

http://technoanswers.blogspot.com/2011/10/how-to-locate-car-ac-refrigerant-leak.html

CAR AC INTERMITTENT COOLING?

http://technoanswers.blogspot.com/2011/10/car-ac-intermittent-cooling.html

What causes INTERMITTENT COOLING on Car AC system?

http://technoanswers.blogspot.com/2011/10/what-causes-intermittent-cooling-on-car.html

Car AC making Noise?

http://technoanswers.blogspot.com/2011/10/car-ac-making-noise.html

BAD ODOR ON CAR AIR CONDITIONER?

http://technoanswers.blogspot.com/2011/10/bad-odor-on-car-air-conditioner.html

How to Recharge Car's Air Conditioner

http://repairhelpcenter.blogspot.com/2011/10/how-to-recharge-cars-air-conditioner.html

For details regarding:--

How does Vehicles Engine cooling system works?

http://repairhelpcenter.blogspot.com/2011/11/how-does-vehicles-engine-cooling-system.html

Engine cooling components working?

http://repairhelpcenter.blogspot.com/2011/11/engine-cooling-components-working.html

How to flush cars radiator?

http://repairhelpcenter.blogspot.com/2011/11/how-to-flush-cars-radiator.html

Car Ac not blowing cold, worked for few hours after Refrigerant charging?

http://schematicsdiagram.blogspot.com/2011/12/car-ac-not-blowing-coldworked-for-few.html

Rear AC is not getting cold on GMC Safari?

http://schematicsdiagram.blogspot.com/2011/12/rear-ac-is-not-getting-cold-on-gmc.html

Heater and fan works, but AC will not blow cold Air?

http://schematicsdiagram.blogspot.com/2011/12/heater-and-fan-worksbut-ac-will-not.html

Car AC clutch fan will not remain Engaged?

http://schematicsdiagram.blogspot.com/2011/12/car-ac-clutch-fan-will-not-remain.html

Location of Front air conditioning drain line on Chevrolet Tahoe?

http://schematicsdiagram.blogspot.com/2011/12/location-of-front-air-conditioning.html

 

 

Location of AC Low pressure port on Chevy Tahoe?

http://schematicsdiagram.blogspot.com/2011/12/location-of-ac-low-pressure-port-on.html

Passenger side AC leaks water?

http://schematicsdiagram.blogspot.com/2011/12/passenger-side-ac-leaks-water.html

Water leaks under dash on passenger side?

http://schematicsdiagram.blogspot.com/2011/12/water-leaks-under-dash-on-passenger.html

Car stalls when AC is turned ON?

http://schematicsdiagram.blogspot.com/2011/12/car-stalls-when-ac-is-turned-on.html

Car AC compressor will not start?

http://howtobyme.blogspot.com/2011/12/car-ac-compressor-will-not-start.html

Engine cooling fans running, but AC compressor will not run?

http://howtobyme.blogspot.com/2011/12/engine-cooling-fans-runningbut-ac.html