2010 335D Climate Control Heating Issue

[Automan]

My 335D has ceased to produce heat. It was never really correct, but it seemed to deteriorate more when I imprudently applied a stop leak solution. I promptly instructed my local garage to do a thorough flushing, and they are certain that the matrix is not obstructed. I am uncertain. I am now receiving little heat from the passenger side and none from the driver's side. No problems are shown by the code reader, and all flap tests seem to be functioning well. I replaced the IHKA panel with one purchased from eBay, however it did not provide any improvement. This suggests that the matrix remains obstructed or that the auxiliary heating pump is malfunctioning. Before proceeding with more flushing, I want to verify the functionality of the auxiliary pump first. I conducted the typical bleed test (28 degrees on IHKA and depressed the throttle, but did not hear any pump activate). I am now uncertain whether my model is equipped with one and have contacted the BMW dealership for an estimate on the component; they seem to be somewhat perplexed as well and I am awaiting their response. Any assistance or guidance would be much appreciated.

[rauman]

The malfunctioning auxiliary pump will not result in insufficient heat, since its role is only for the rest mode. When the engine operates, the primary water pump pumps coolant through the matrix.

Does the engine attain its operational temperature? Assuming it is an M57 engine in that vehicle, the statistics indicate a propensity for failure.

[Automan]

Thank you for your observation; I have come to understand today that the Aux is just for REST, whereas mine has the ALL button. BMW has verified that my car lacks an auxiliary pump. I will verify the engine temperature tomorrow; it should exceed 90 degrees. My current idea, if the engine temperature is satisfactory, is to attempt to extract the matrix without disassembling the column and dashboard, rather than doing a flush from the engine compartment. Certain YouTube videos assert that it is possible, but others contend that it is not. It likely depends on the specific model. If I can remove it, I may attempt to clean it or just get a new one. I have just this week available, since I begin a new work next week.

[Squirrrel]

Increase the thermostat by one degree.

[Automan]

ello everyone, the dashboard's secret menu indicates a temperature of 89-92 degrees Celsius, suggesting that the thermostat is functioning properly. It seems that flushing or matrix removal is now presenting significant challenges. I discovered this intriguing link about flushing: DIY: Flushing the E9x Heater Core (Exercise Caution!). I will attempt this first.

[Automan]

https://www.e90post.com/forums/showthread.php?t=2093692

[Automan]

I am enquiring if the issue may be attributed to a deficient water pump, capable of circulating fluid through the engine block but insufficient for circulation through the matrix. Your insights would be highly valued.