A/C Compressor relay

In your 2006 you would be looking a long time for a compressor relay. Your compressor is not driven by a belt and electric clutch, it's driven by its very own, high voltage, three phase electric motor, which is driven at variable speeds by three-phase AC waveforms fed to it from the inverter assembly, under orders from the HVAC computer in the dash.

There are some pricey parts in that picture, so you probably don't want to pursue the old "replace things until I get lucky" repair strategy. In the new era, to troubleshoot the way God and Toyota intended, you would ask the HVAC computer to tell you what the trouble is, and then fix that.

In a 2006, starting with the power off, hold down both the 'auto' and 'recirc' steering wheel buttons, while you turn the car on (two POWER presses without touching the brake) ... or READY (one POWER press, while pressing the brake). Wait for a beep and the multifunction display switching to the climate screen. Note down any two-digit numbers shown in the top right corner. These can be looked up in the repair manual.

I said ON or READY because I don't think it really matters ... I've seen a post that says to use READY, I know just ON works on my Gen 3 (and is what the manual says), I think you get the same codes either way.

-Chap

 

Sorry, didn't see this right away. Pretty sure 21 is the code for solar sensor in the dark. Not a problem if you actually are in dark or shade when you ask for codes. Only indicates a problem if still shown even when sunlight is falling on the sensor.

But I strongly recommend checking the manual rather than trusting my memory on codes.

So, if that was the only code shown, then whatever other problems exist will have to be tracked down the hard way.

-Chap

 

While there isn't a relay, there should be a fuse somewhere that would be worth checking. Surprising the ECU didn't give you a trouble code. Maybe more info would be available over a miniVCI check of that ECU.

 

The high-voltage system has very few discrete, replaceable fuses, as far as I know ... I'm not aware of any, other than the main one that's co-located with the orange service disconnect at the traction battery.

-Chap

 

There is a ac fuse inside the inverter.

 

I know this is an old thread but on my 04 model my a.c. doesn't work. I get codes
00, 13, 62 and 74. The copressor doesn' cycle at all, and it reads over pressure on the low side and it does not change when I turn the a.c. on, nor do I see anything in the sight glass. I' assuming the amplifir is out, but it' also throwing 74 so I'm not surem I made a post, but since I just registered (finally) it's still waiting admin approval and has been for a few hours.

 

I have same problem Help! A/C not work | PriusChat

 

Same problem here and very perplexed. Did you (Greg or Ower) figure out the issue. It seems to me that Prius Chat is dead, because NO one seems to posting and responding.
Carl

 

Any fix?

 

PriusChat isn't really dead, but some posts get more responses than others,

It's been a year or so since Greg Kitchens posted the trouble codes he was seeing (00, 13, 62 and 74).

More recently, Qwer posted "I have same problem" but linked to a thread where the code was 23 instead, so it wasn't the same problem.

Center of Gravity has posted "same problem here" but not said what the codes are yet, so nobody knows if it is or it isn't.

Threads that get too much like that can end up being sort of skipped over by other PriusChatters who are looking for places they can give useful answers.

There would probably be more responses to a post that clearly states the symptoms and the trouble codes, and even better if the codes have already been looked up in the manual (more info) and briefly described in the post, to jog the memories of other PriusChatters who might want to help. (As awesome as we all are, we usually don't really have the whole book of trouble codes memorized.)

Since somebody has to look the codes up anyway, it can save time if one person does that when posting, instead of the multiple people reading the post (who might see the post and think "hmm, interesting, I'll come back to that one some time when the manual's in front of me if I remember to" and then not remember to).

 

I just had same problem, 2006 prius. My codes are 21, 23, 43. I do not have a manual but I found the 23 code was a pressure switch, I replaced the pressure switch that is tight next to the high side terminal and it did not fix problem. Any Ideas would be appreciated.
Thanks

 

Codes can't be interpreted quite that simplistically. The fortune cookie "pressure switch" might show up next to 23 in some listing of codes, but that doesn't mean the computer is telling you the pressure switch is bad; it has no way of knowing that. It can only be telling you that the signal it's getting from the pressure switch is surprising, which can mean the switch is bad, or the wiring to the switch is bad, or the switch and the wiring are all good and the pressure in the system is surprising. It's up to the human to take the clue from the computer and run it down to the root cause.

There will usually be several pages of ideas for doing that, in the manual where the code is listed.

 

Code 23 is DTC B1423 which means there is a problem with the system pressure. Either it is too low (below 28 psi) or too high (above 455 psi.)

Since you replaced the pressure switch, can I assume that you were able to evacuate the system with a vacuum pump, and recharge the system with R-134a?

If my assumption is correct, your next step would be to hook up manifold pressure gauges to the low side and high side ports so you can see what the pressure readings are.

If my assumption is not correct and you did not evacuate / recharge the system, that needs to be done next.

The high side pressure should be 198-228 psi when ambient air temp is 86-95 degrees F, max fan speed, max cool temp setting, doors open. The low side pressure should be 22 to 36 psi under those conditions. Obviously it is assumed the air conditioner compressor is running.