robert kaylor
Junior Member
Ok my 2013 4.7 1500 is putting out barely lukewarm heat on the drivers side, passengers is hot. The truck has a single zone system.
Ive changed the thermostat and bleed the system thinking that might have been the problem. Flushed the heater core (with just water, no chemical). Thats when I realized it was just the drivers side that was the issue.
Tried reflushing the core with letting CLR sit in the heater core ~ 20mins as I seen where the single zone systems can have issues where the lower core that heats the driver side can have some issues.
Also Ive seen conflicting info as to whether the single zone systems have the additional right temperature actuator on the rear of the heatbox that controls the blend door. Ive checked the actuators on the front of the heatbox and all seem to be in working order. From the diagrams I've found on the forum the Left Temp Actuator (Drivers?) works fine. Doors on the passenger side also seem to be working just fine when manually moved. But I cant confirm whether there is an additional actuator on the rear of the box that might actually be the one that controls the driver's side blend door or not. Can anyone confirm this in the single zone systems.
If its the actuator anyone have any suggestions short of pulling the entire dash to replace it. Is there a way to confirm its bad before tearing everything out.
Any other suggestions to try
Ive changed the thermostat and bleed the system thinking that might have been the problem. Flushed the heater core (with just water, no chemical). Thats when I realized it was just the drivers side that was the issue.
Tried reflushing the core with letting CLR sit in the heater core ~ 20mins as I seen where the single zone systems can have issues where the lower core that heats the driver side can have some issues.
Also Ive seen conflicting info as to whether the single zone systems have the additional right temperature actuator on the rear of the heatbox that controls the blend door. Ive checked the actuators on the front of the heatbox and all seem to be in working order. From the diagrams I've found on the forum the Left Temp Actuator (Drivers?) works fine. Doors on the passenger side also seem to be working just fine when manually moved. But I cant confirm whether there is an additional actuator on the rear of the box that might actually be the one that controls the driver's side blend door or not. Can anyone confirm this in the single zone systems.
If its the actuator anyone have any suggestions short of pulling the entire dash to replace it. Is there a way to confirm its bad before tearing everything out.
Any other suggestions to try
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