Clarification on Blower Controller FET ASSY

[Dijkstra_Redanian]

Hey Tesla Model S owners! I’m doing a bit of digging into the HVAC system on the Model S and trying to sort out whether the “Blower Controller FET ASSY” listed in parts catalogs is the same as the traditional blower motor resistor.

From what I’ve learned, many newer vehicles are moving away from the old-school resistors and opting for brushless blower motors instead, which simplify things a bit. Tesla has already done this for the Model 3, but I know the Model S and X still rely on a resistor for the HVAC system.

I’ve seen some used blower resistors floating around on eBay, but I haven’t been able to track down the exact Tesla part number or confirm if the FET assembly mentioned in the catalog is just their name for the resistor.

Has anyone dealt with this before or found clarity on whether the FET assembly is a direct match to the blower motor resistor?

 

[mygingerbreadman]

Since a FET can be a "field effect transistor," I assume that active electronic components are used to regulate the blower speed instead of a passive resistor.

You can check this link for more information: epc.tesla.com.

 

[Rainb000wBright]

Based on the Model S diagram, I believe the eBay BMRs should physically fit within the blower motor housing. However, I'm struggling to confirm if the BMRs listed on eBay actually match the FET assembly part number. My Google searches for this part number have yielded very few results.