Why is the common fan-only-high issue not a recall?

As far as I know, the old style is widely available in aftermarket versions if you're willing to go that route. Personally, if the change was to alleviate all the burnout problems of the old style, I would rather go new style instead of keep having to replace the old ones (especially since the likelihood of needed replacement MAY be higher with aftermarket resistor packs).

The only downside is that, as far as I know, there really hasn't been enough switchovers for long enough to REALLY say if the new one is ACTUALLY better than the old one (assuming that it's the REAL culprit in the ongoing issue).

Edit: What you could do, I suppose, is stick to the old style if yours burned out recently, and watch for problems being posted about the new versions. If it seems like the new version is working out well, the next time your replacement old style burns out, THEN replace it with the new one. It would save you the time/effort of fiddling with the wiring if it ends up still being a problem.

 

Yes good point about aftermarket.

Im thinking in terms of trading one problem for another. Poor connections at the original resistor vs potential issues with cutting & splicing factory wiring with crimp connections. I know the chances are low if done properly, but then again resistor failure doesn't seem all too common considering total production numbers from 2005-2018.

Just the pessimist in me when it comes to crimp connectors I guess

 

Try typing tacoma blower motor resistor on Amazon. Plenty of hits.

 

On Rock, the only version available is the old style (obviously all aftermarket). NOTE - this is search under 2013


Poking UP through the years SEEM to indicate there is no aftermarket version (at least on Rock Auto) as yet. As you go up in the years, it's all the same old version until you hit about 2021ish (I don't remember) you hit a point where there is no option for the resistor pack.

 

From my experience, the blower resistor is usually misdiagnosed by diy’ers as the problem. The culprit is usually either a bad connector at the resistor plug or at the blower plug. Pull out the plug and look at each connector; a burnt mark will point to the bad pin connection. Sometimes, just removing and re-inserting the plug will fix things, but only temporarily. You need to remove the pin, clean/sand off the burnt matter and reinsert with dielectric grease. I went through both situation; still have oem resistor. On the blower the connector melted beyond use; I spliced 12-gauge wiring and narrow .187 female blade connectors.

 

another thought is the blower motor is drawing too many amps and the weak link is the resistor and the wiring connector, if after replacing the resistor its still an on going issue I'd do a few draw tests on the blower motor, that being said I did replace my resistor and harness 3yrs ago with aftermarket parts, no issues since

 

How much does a dirty cabin filter play into this? Would a dirty cabin filter cause the blower motor to work harder?

 

It would restrict airflow which could make the resistor get hotter than it should.

Most blower resistors have a thermal fuse built in that will blow in the event of the resistor getting too hot, once this happens the resistor is dead.

Exsessive current through the resistor from a failing blower motor can also cause the thermal fuse to blow.

The melted resistor connector isn't exclusive to Tacomas, it happens on many vehicles (GM and Ford trucks are particularly bad about it).
IMO it's the design of the connector pins, they are too small and the design of them causes them to lose tension over time which causes arcing and heat geneartion which eventually leads to a failed connection and melted connector.

 

We can thank AC delco for these headaches.

When I worked in the domestic world it was common to replace the blower as well due to draw causing overheating of the resistor.

Heck dodge wouldnt even sell a resistor without a fan. No recalls though...

 

You can completely block the inlet and or outlet of the fan blower and it will draw less current for the motor. Seems counter intuitive, but that is a fact. Less work being done requires less energy.

http://hvacrfundamentals.blogspot.com/2009/08/understanding-centrifugal-fan-motor.html

 

Other than safety, and sometimes as customer satisfaction (good companies that value that still exist)...

Recalls are always a numbers game. Will it cost more to *recall* or will it cost more to *not recall*. And most of the time, even in the case of safety this same metric is used.

 

This is true - restricting air flow reduces amp draw because the the motor does not work as hard for a given setting. This is because the biggest power draw is caused by air drag of the impeller/blade/what have you.

With less air draw, the motor does not fight as much because there is not as much air flow drag

 

My 1991 Tercel still has the original 4 fan speeds.
My 2009 Tacoma doesn't.
I have NEVER replaced a fan blower motor resistor in any of my 12 vehicles (including 5 Toyotas, all with more KM's than my Tacoma).
Either I'm incredibly lucky, or the fact that there is a TSB for this particular model means that it is a faulty design. I'm going with the latter.
Not a big deal, but it is a design flaw.

 

Totally. But the other side of that same coin, is you have less (or zero, in an extreme case) airflow through the motor and over the resistor block to cool them. So it’s not like a restricted filter is a good thing for the components either.

 

I was a tech for a Ford dealer...this was very common in every vehicle that existed. It was always only high speed that worked - because then it didn't go through the resistor at all.

 

Yes and the resistor will burn out in short order.