I have been having trouble with my ac blowing hot air at low speeds, and found my fans on the front grille are blowing air outwards instead of into the engine compartment. Im hoping its an easy fix, but any information on fixing this sort of issue would be greatly appreciated.

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    I don't know why or how, but your polarity going to the fans is reversed. This might have been done because someone plugged them in backwards, but that seems kind of hard to go with (plugs can usually only go one way). The only way I could think of is if you had some work done, or if the front end (or fans) got damaged someone and repair work had to be done to it. – Pᴀᴜʟsᴛᴇʀ2 May 14 '16 at 0:49
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    You may trace the wiring back from the connector to see if it is spliced in anywhere. If it isn't, you're probably going to have to make a place to change the polarity. If you go this route, solder the wires together and cover them with heat shrink ... don't use a butt connector, as the fans draw too much current. This tends to wear on the fan motors and the wiring may get hot, melt, and cause shorting issues. This is just my thinking ... someone else who has more knowledge may have a better answer for you, so give this some time. – Pᴀᴜʟsᴛᴇʀ2 May 14 '16 at 1:00
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    You could repin the connector instead of messing with cutting and resoldering the wires. At most this requires a small pocket screw driver and a small pick. – Ben May 15 '16 at 1:32
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    Will the physical fans fit the other way around in the housing in the prius? This might be the mistake if the wiring is all intact – tallpaul May 18 '16 at 20:57
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    Never solder wires in an engine bay. The heat cycles in that area will cause the solder to fatigue and fail. You should always use high quality crimp connections in an appropriate size for the load. I use this style, with heat shrink tube: amazon.com/gp/product/B01B2A8R7E – cscracker Dec 2 '18 at 14:20

As various comments state, you have either had the fan replaced back to front (which I don't think can happen in a Prius, looking at the layout) or the wires were attached with the wrong polarity.

If you can take it back to the shop that did the work, they should sort that out for free as it was a mistake, but if you want to do it yourself it's very straightforward. No soldering required - these use spade terminals and crimp connectors so either look for the connector block and swap the connectors over (they are easy to remove) or change the wires over at the fan end.

This video shows useful detail


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