My heater doesnt blow on anything put #4 setting

check the controller an vacuum lines

if your heater dosent blow through the vents at all you have a bad blower motor usually located on the fire wall of most vehicles

make him do it again... ?

does not blow in any speed setting? if it blows in high you may need a resistor block if it doesnt blow at all then you may have to look at your blower motor.

There amy be a problem with the heater relay switch which is not allowing it to switch over to heat.

I JUST PUT A HEATER CORD AND THERMOSTAT ON A 97 GRAND AM AND NOW I DO NOT ANY HEAT AT ALL.

Your fan uses resistors to reduce the speed of the fan. Hi speed doesnt use the resistors and that is why it runs on hi. Standing in front of the car, all of your heater housing is on the left side of the firewall You will see a connection with about 4 wires That look like they go nowhere. Take the couple screws out and pull it out. You will be able to see the burnt one.Jump out the burnt on and that will give you another speed or two.

working on 4 and 5 speed that the resistor that broken cold air you got to move the selector to see the motor that move the trap hot and cold sometime when the motor was not move to the hot side for a long time its jam the motor on the passager side under dash put to hot and gently tap the motor tanks pierre

i think you have a short in your blower motor. the resistor block which reduces also your speed could have damage also from the short of your blower.

tnx 4 using fixya,

drcool

The heater resister switch has gone. You need to strip out the box and put a new switch in which costs around £20