Hi and thanks for looking and hopefully any help. I Have a 2000 Chrysler LHS with a 3.5 engine. I am experiencing little or no heat. I thought the problem was fixed. So far I have had (because of a past coolant leak issue) replaced the heater supply line, heater return lines, upper and lower radiator hoses, coolant overflow tank and all hoses to that, thermostat, supper flushed the system, and even though it shouldn't matter, the head gaskets were replaced as well (needed anyway) The heater core was replaced a year ago and both lines feel hot as they should. The climate control module has been replaced as well. I did the self diagnostic with it and no codes came up at all. I am at a loss. I Know this will sound strange or silly but this seems to have started after going through an automatic car wash that had the bottom blast. COuld it have knocked a vacuum line or something? Can anyway tell me where to go on this? THanks

 

The water pump was replaced twice a year apart due to one from the manufacturer that was faulty. Coolant levels are fine and the blower motor works well on all speeds.

 

If all the mechanical things have been A replaced then prob looking at a blend air door or motor.

 

Motor as in engine? Or another motor I am not familiar with?

 

Oh I hope you meant the actuator motor.

 

yes a blend air door motor

 

Yes it does sound like a blend air door is stuck or the motor failed.

The system draws outside air through the cowl opening at the base of the windshield. Then it goes into the plenum chamber above the Heater A/C unit housing and passes through the evaporator. At this point airflow can be directed either through or around the heater core.

Airflow can be adjusted by the blend-air door with the TEMP control on the control head. After the air passes the blend air door, the air flow is then directed from the PANEL, BI-LEVEL (panel and floor), and FLOOR-DEFROST outlets. Air flow velocity can be adjusted with the blower speed selector switch on the control head.
Ambient air intake can be shut off by closing the recirculating air door. This will recirculate the air that is already inside the vehicle.

 

I am having the same issue with little or no heat in my step daughters 2000 300m. I am just beginning to diagnose it too. I did the diagnostic mode on the head unit and it is not showing any codes. If a door is stuck or malfunctioning, should a code come up? The car itself does not overheat and the temp gauge stays just below halfway, so I am hoping it is not a thermostat or water pump issue, and the coolant level appears to be normal.

 

Just updating on the issue here....took it to mechanic. Found that it was an blend door that was stuck. They worked with it for awhile and got it to work. Also did a power flush of the heater core. Step daughter is nice and toasty now. Knock on wood, and all that other superstitious stuff, that it keeps working.

 

Sorry, this is a really late reply but the issue was resolved. Turned out to be a blocked heater core due to an additive that was used by the previous owner. It was still in the system. It has heat and ac fully now.