Climate Control

[spatula]

This query concerns the climate cotrol of my 2010 Charger. A simple 3-knob control unit I'm quite certain is identical to many Ram systems. The problem I'm experiencing exists when the heat is "off." The blower motor is off, the temp is set to cold, but the blower still blows hot air through the vent ducts. I'm nearly certain I can rule out blender door failure as they all function "as intended" when in use. I suspect it's a heater relay, resistor, or the control unit. It is my opininion somebody here has experienced this issue in the past and, hopefully is willing to share their resolution. Otherwise, I will commence replacing components starting with the cheapest and ending with the most expensive.

Thank you in advance.

 

[HemiLonestar]

No. the LX setup is different. On the cars EVERYTHING is electronic and you can get trouble codes for damn near anything. This is part of the reason it stopped being a CEL (check engine light) and became a MIL (malfunction indicator light). Have you tried to pull codes?

 

[crash68]

I have to wonder if your just feeling heat radiat from the vents since the blower is off and the blend along with mode doors have gone to a standby position.
Does the issue go away once the fan is ran at a minimum speed?

 

[spatula]

I have to wonder if your just feeling heat radiat from the vents since the blower is off and the blend along with mode doors have gone to a standby position.
Does the issue go away once the fan is ran at a minimum speed?

I have often asked myself this same question but, there is in fact (what seems to be) blowing air. I suspect the obvious thing to do would be dropping the blower motor to witness it moving when the selector is set to off. I could probably do it with an amprobe if the wires are easily accessable.

 

[crash68]

Does it seem to only happen while the truck moving? A low pressure mass occurs over the cowl area of most aerodynamic vehicles, that can actually suck air out of the vehicle through the vents and defrosters. The movement of air can give the sensation of blowing air also.

On the flip side of the topic, unless your traveling through an area of odor, smoke, dust, etc, why do people like to drive in a vehicle without at least the HVAC system blowing in fresh air? With as air tight as vehicles are nowadays, keep the blower running. Ram truck vents are low velocity (not to be confused with volume) so even at mid-range fan settings there's not much noise, a whole lot quieter than opening a window.

 

[spatula]

UPDATE: I dropped the blower motor and the motor is in fact "off" when the selector knob is in the off position. All selected speeds function as intended.

I can only surmise I thought the selector was in the off position, when it was actually on the low setting.

Thanks for the input fellas.