(Attached is a schmatic of the control circuit and the datasheet of the original and replacement mosfets)

My car blower motor uses a 2SK2313 (K2313) mosfet to control the speed.

I was having a hard time finding a replacement of either a k2313 or nte2920 (replacement part number) so after doing a comparison I found that a IRFP064NPBF had fairly close specs...

After installing the IRFP064N, it doesn't work correctly. My blower atleast works currently and the feedback to the climate control computer is good enough so my air conditioner compressor to engage, but the blower is stuck at one speed and you can't turn it off either...

I have a feeling the issue is the RDSon values / resistance but Im just guessing.
I've attached a datasheet for both the original and the replacement, and the circuit schematic of the control circuit.

Basically I'm trying to find a replacement that will work correctly that is readily available. Preferably a IRF mosfet if possible.

 

Why did you replace the transistor?? Did it fail shorted, o open???

 

The original FET has a "Logic-Level-Gate",
The replacement FET uses a relatively "standard" Gate-Voltage range.
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Why did you replace the transistor?? Did it fail shorted, o open???

Hey thx for the reply! Yes sir, I replaced the original 2SK2313 with a IRFP064N. Thats where my original question comes from. It failed open so the blower didn't work at all.

It seems though that @LowQCab may have an answer why I'm having trouble...

The original FET has a "Logic-Level-Gate",
The replacement FET uses a relatively "standard" Gate-Voltage range.

Oh well if that's the case, I can see how that would cause an issue...

So I need to find a mosfet with similar specs but that has a logic level gate. Correct?

I see that the original mosfet have a "4v gate drive" and a Gate source voltage of +/- 20v. Which means that it can be turned on with as little as 4v and upto 20v. Correct?

 

I miss-interpreted the specs of the original FET,
with a little bit of language translation mix-up thrown in,
This is not uncommon,
and is a great reason to attach the Spec-Sheet of any Semiconductor that You may refer to in the future.

The original FET requires in excess of 10-Volts to achieve it's lowest RDS-On rating,
it is NOT a "Logic-Level-FET".
Notice the Voltage of the "Miller-Plateau" in the Graph below.
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