There is a differential vane in the AC ductwork that regulates the flow of hot and cold air into the two halves (driver/passenger) of the system. Failure of this mechanism is one of the more notorious problems with the LS.
Check the following items............... 1. A/C heater controller. 2. A/C heater controller doors.
heater control valve is bad on the drivers side.
COULD BE A BAD HEATER CORE COULD BE A BAD HEATER CORE sounds like the heater control switch needs replacing.if that doesnt fix it, you need new heater core
The heater control valve is bad. Sometimes the dual heater control valve will go and the AC will blow full heat.
make sure both knobs are all the way up on red for heat...
A broken blend air door is the most likely cause on a Jeep Grand Cherokee.
An automobile's heater that blows only cold air could either be a faulty thermostat or, more likely, a faulty heater core. A trip to a mechanic or shop that specializes in radiator and cooling system repair should be able to diagnose and repair any problems.
One of the temp blend door actuators has failed.
Had the same problem. In my case it was the actuator motor inside of the panel in the passenger footwell. Check to see if the flap is binding or it is the actuator motor itself.
I have the same problem with my 95 olds 98 regency, did you find anything out?
Heater core changed three years ago,I changed Thermostat Heater still blows cool air.
The 2003 Lincoln Navigator air conditioner airflow is directed by lending doors. The blending doors open and close to direct the cool air. The blending door for the passenger side vent is probably stuck closed.