The issue is a recurring problem with the Left Heat Regulating Valve N175, namely an intermittent open circuit. Despite already replacing the Heat Control Valve (HCV), the problem of constant heated air persists.

[WhisperingWillow]

I am aware that there are several discussions on this topic, but my problem has some unique aspects. I installed a new High Control Valve (HCV) above the drive shaft of the automobile. Despite resetting the system, the fault code has reappeared and I am still experiencing a consistent flow of hot air regardless of the temperature setting on my climate control. The switch is functioning well since I just installed a new climate control module in the vehicle. When I turn the dial, I can perceive a noticeable increase in temperature. However, even when set to the lowest setting, warm air is still being emitted. The increasing temperatures are becoming quite bothersome, especially after lengthy drives when the automobile becomes extremely hot.

Is there a fuse that I am overlooking for the valve?

After resetting the issue, I conducted an individual test on the N175 valve using VCDS, and the fault reappeared.

Has anybody else had this problem or can anyone provide any advice?

[nimbuye5]

What is the status of the AC compressor?

[WhisperingWillow]

In the absence of air conditioning, the temperature should transition from chilly to warm, rather than being too hot. I feel that the G395 error pertains to the sensor, which may be changed. However, the heat regulating valve fault is distinct from the AC sensor issue, in my opinion.

[nimbuye5]

My AC compressor was replaced in 2020. During that period, my OBD11 did not generate an error code.
The left heat regulating valve was updated last year. At that point, a strong gust of hot air was emanating from the left ventilation opening, whereas the air from the middle opening was comparatively less heated. I received error code 00737.
Subsequently, everything has been OK.

[WhisperingWillow]

I have substituted the left heating control valve, in fact, I have changed the whole component, but the malfunction has resurfaced.

[migueldosantos77]

After replacing the valve, I recommend inspecting the wiring and connections for any potential problems.

[WhisperingWillow]

Upon your comment, I revisited my VCDC code and saw that mine indicates an open circuit instead of a short circuit, which is often the issue encountered by those who have changed the valve (based on my observation). I have scheduled an appointment for an electrical diagnostic at a garage in April, upon my return to the country. Hopefully, the issue is something trivial, such as a faulty connection on the socket causing an open circuit. Wiring problems are very undesirable since they might result in significant financial losses.

[Gianni682]

I already encountered this issue. The solenoid in the engine compartment, responsible for controlling the amount of warm air that passes to the air conditioning, was found to be defective. I have replaced it, and as a result, I am now able to adjust the warm air once more.

[WhisperingWillow]

Is there a specific component number associated with this solenoid? It is possible that the one I have replaced is located in the drive train tunnel. There are two solenoids that redirect the heat to either side of the cabin.

[Gianni682]

Regrettably, I do not possess the desired information. My Audi R8 is now covered by a warranty, and the dealership repaired it at no cost to me, as per the terms of the policy. They provided me with an explanation of what was incorrect. Additionally, a regulating heater valve was changed.

I am now experiencing the problem of the automatic mode disengaging after a certain period of time. The manual mode works well, but, I get the sensation that this occurrence is not expected. Fortunately, I am still covered by the warranty and I have found a helpful dealer (not affiliated with Audi) who is now investigating the issue.