Hello,
First check to see if the heater water valve is functioning. The valve movement itself can be viewed by removing the 2" diameter flat rubber grommet on the firewall under the hood (upper left). Move the left lower red lever from side to side to see if you can see the water valve move. Max heat is with the lever switched left-most to the red arrow
The Blue lever (air volume control lever, upper left) moves the air intake flap in the hooded cover in front of the windshield and controls the volume of air coming into the car.Watch to make sure that the flap in the hooded cover moves up and down when this lever (blue) is moved. Left-most is max air flow. The grey lever (air distribution lever) directs air flow to the defrost ducting or the foot space ducting or a combination of both depending on the position of the lever. The red lever on the left is the main heat control. It moves the water valve and the amount of hot coolant entering or not entering the heater core. This lower left red heater lever also regulates the amount of hot air entering the left half of the car. The right side heater valve regulates the amount of hot air entering the right side of the car.
Max heat would have the blue lever left-most on the blue arrow, both red levers on their respective red arrows. The grey lever would be set to direct the heated air to the windscreen or foot areas as desired. The heater fan speed control (just right of the levers) would be adjusted to the desired fan speed.
Max ventilation would be blue lever left-most on the blue arrow, both red levers moved all the way away from their respective red arrows. and the grey lever is set to direct the ventilation to the foot or windshied areas. With this setting the fan switch can be used to increase ventilation air flow.
The AC system and the heater systems are mostly independent of each other on these cars. Note the separate controls for fan and temp on the heater unit.
