A/C works a few seconds / stops blowing Code 21

welcome!
you probably need a new fan motor circuit board assembly.

 

... know as the fan controller and sits inside the fan duct or, you need a new fan motor. Both are know to fail.

The 21 is aka B1421 and simply mean the solar sensor does to detect strong sunlight. So as long as that his the case (you were not in strong sunlight), you can accept that as the truth and move on.

As you did not get any other codes, I don't think you have anything more serious. The fan motor and controller failing will not set any codes.

 

Yes, have heard and done some work on a car's AC system, showing such a code about a solar sensor blablabla.

In some cases, the solar sensor code only comes up, when the solar sensor on the extreme right of your dash, has fallen inside the dashboard, exposing it to darkness, or when the car is not exposed to sunlight, if its parked where the environment is dark.

Check to see if the solar sensor hasn't fallen off, or removed from its position.

It kinda receives suns brightness (intensity) maybe, and relays that information to the AC system amplifier to now gauge cabin air requirements, then the AC system compressor kicks in. If there isn't any inputs from that sensor, you'd always be having a work and on situation.

Ins some situations I have worked on, Camry hybrid, and some prii, locating the sensor, and glueing it on its position, tends to solve the problem, with maybe some addition of refrigerant in the system.

Hope this kinda help ya!?

 

You can usually ignore error code B1421 on your 2004-2009 Prius | PriusChat


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