HELP: Heater fan blower resistor unit

[radiomans Lurker Find all posts View Profile Close radiomans]

Hi all
I have been having some probs with the heater fan, it only runs at full speed, so i removed what i was told was the
blower resistor, this is a pic of it.

There are a few components in this unit, a NPN Darlington Transistor (2sd1460) mounted on the heatsink .
And mounted under the plastic cover at the top of the pic, are a 2.2k resister and a 2.2uF @50v cap.

After finding that i had a few npn darlington transistors (mj110016), i started to strip the unit apart to replace the
transistor, only to find that there is another part that could not be seen untill one strips it down, it is connected to the
base pin of the transistor, the part is in the red covered wire on the left hand side of the above photo, it is clamped
down to the heatsink by the plastic strap,
It looks to me like it could be a thermo type fuse, i tested it and it was open circuitm so i left the 2sd1460 transistor
on the heatsink and bypassed the "fuse", replaced the unit into the truck and hey we now have low, med and high speed
on the fan , Can anyone confirm if this "fuse" thingy is a thermo fuse, and what type it could be ??
I don't want to run the fan resistor for to long without one fitted.

Thanks for reading this
Regards
Howard

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Re: HELP: Heater fan blower resistor unit

Could be a thermo fuse, you will need to uncover it. If open circuit it is blown.

It will have writing detailing its type if it is.

[radiomans Lurker Find all posts View Profile Close radiomans]

Re: HELP: Heater fan blower resistor unit

Hi
Yes it has writing detailing its type on it, but it is so small my eyes can not read it ops:

I think it says "110 deg C 2A", Yeah thats what my wife says it is too :!:
so i need to find something like this, will look at a few online parts sites.

Regards
Howard

[coffeeking Lurker Find all posts View Profile Close coffeeking]

I realise this is a very old thread but I'm having similar issues on a 4runner with this unit in place but I'm seeing 12v across the blower connector when not connected to the blower. The moment I connect it I drop to a few hundred millivolts, as if whatever is feeding it is unable to supply the load. According to the patch wiring diagrams I can find online, it looks like this is the only thing between the fan and the power relay for it, but mine has the "auto" control for the JDM climate self-adjustment setup - im not sure how this differs as I can't find diagrams. Powering the blower directly gives a perfectly happy blower.

The funny thing was that it didn't fail in the usual manner (works on full but not others) - it started by not working on anything without 10 changes of switch position, then suddenly it would work on any setting. Now it's gone entirely.