2004-2009 Prius Coolant Control Valve Repair P1121 Gen 2

[@Caladan1616]

Great video! I was able to replace the valve in my son's '08 Prius and save him the $900 he was quoted by a shop. Thanks a lot!

[@ourvdo549]

Thank you! I am happy to hear it helped you!

[@antcw7837]

This is shadetree mechanics at it's finest. Thank you, this is gonna make the job on my mom's car a lot easier!

[@ourvdo549]

Thank you! Glad I could help,

[@pfoxhound]

2 inverter mounting bolts, lift the bracket of inverter. 1 bolt, 1 nut, 3 hoses and done...

[@jtm65]

Good clear step by step process on this CCV replacement. Thanks for taking the time to share your knowledge. Be Blessed - Take Care

[@ourvdo549]

Thank you for the kind words. Blessings to you as well!

[@mdhsabh]

Disconnecting the hybrid battery isn't necessary. Thanks for the video, I referred to it before I replaced my coolant valve in my '05.

[@ourvdo549]

Thank you for the kind words! Just wanted to be safe with the hybrid battery and only takes a minute.

[@noelybro]

was it leaking? i have a ccoolant leak and im thinking its the coolant control valve. thanks

[@noelybro]

05 prius as well

[@intheharness]

Thank you that was a great video and you did a good job explaining and finding a good way to accomplish this task. Enjoy

[@rumingjiang69]

Thanks for the video. Your method worked well for me today.

[@ourvdo549]

Glad it helped

[@deborahpayne9268]

To ease access, remove the bolt for the inverter and place a wooden 2 x 4 block between the inverter bracket and frame to lift it a few inches.

[@patrickwagner5407]

Wow, exactly what we needed. Great video.

[@ourvdo549]

Thank you! Glad I was able to help!

[@blawler]

Thank you for posting this. Saved me about 400 bucks.

[@tomhumphreys237]

When this valve goes bad it can trigger the abs warning lights (I.e. steering angle sensor, yaw rate…). The bad valve will reduce the voltage throughout the CAN and send crazy errors. Also clean the connector. It is subject to corrosion.

[@sokunhi11]

I think 2007 Gen 2 not Gen 3 Thank you so much for this video.

[@ourvdo549]

You're right! Thank you for pointing it out! I thought I had checked this and confirmed correct Gen originally but stand corrected. have updated and corrected to Gen 2.

[@boobtubeakatv1296]

@@ourvdo549 Yes... I got the edited copy as that Gen II is what I heard and seen 👀🤔🤪🤩🤡🤣🤣🤣

[@cubangeorge]

Headlight removal is unnecessary, but thank you I know how to do the coolant pump now !

[@RogerPack]

But hugely helpful to be able to see in there...

[@leehooligan]

I couldn't have pried off the hose clamps, let alone clamped off the hoses with everything in the way. There is so little room inside that space, the removal of the headlamp is an absolute must, unless you're plasticman with spaghetti arms.

[@RalphLegnini]

A couple of questions - the vice grips from Harbor - did you get the 6" or the 8" ones - hard to tell from the video. Also - most other videos say to bleed/burp the system after replacing this part - but they didn't clamp the 3 hoses. If you clamp the hoses like you did - there is obviously some loss of fluid - the amount that is in the part and the residue amount from the hose after the clamp - so my question is - once the new part is installed and the hoses reconnected - were you confident that no air got in the system and the fluid just needed to be topped off rather than needing to bleed the system? Thanks so much - great video!

[@ourvdo549]

Thanks for the comment! I used the smaller 6" ones and as you can see they worked great. I topped off the fluid and checked it for the next couple days and it was fine - no error codes and ran great!

[@mdhsabh]

5:55 "That's actually the coolant pump...." could be confusing. The Prius actually has 2 coolant pumps, one for the electronics (THIS PUMP, called the inverter coolant pump), and one for the engine (on the other side of the engine, commonly called the "engine water/coolant pump"). The coolant for this inverter coolant pump is in the white reservoir on top of the engine (you can see pink fluid in it). You can tell if this pump is working by checking to see if the fluid in the white reservoir is moving. But the engine coolant pump reservoir is at the front of the engine, and filled thru the overflow bottle on the front of the engine or directly at the radiator. Note: the engine coolant system and the inverter coolant system are totally different, separate systems.

[@cmc22101]

My Prius is 2002, looks like this part no is not what I need? Please help!

[@cmc22101]

They say it's a good ideea to change inverter pump. Is there a site where i can order part, everywhere they have 2004 and up...thanks

[@animal3962]

This video is very valuable sir .. I am from Sri Lanka🤗

[@rockcrusher4636]

Excellent video, thank you.

[@stevengranados4975]

Thank you for the tips. Helped me out today.

[@ourvdo549]

Glad to hear it!

[@zeeman2594]

great video! For a while I was hearing constant see-saw kind of noise from the valve, as it is opening and closing, then after a while it failed and it threw the error P1121 . So, I replaced the coolant valve and I have proper amount of coolant. The error is gone but but constant see-saw kind of noise is still there. What could be the problem? Is that noise normal?

[@RogerPack]

I don't think it's normal..if it's an aftermarket replacement valve it "might" be OK, the computer is just recalibrating? If it keeps going forever that's not good. If it comes up suddenly and often (especially if accompanied by a check engine code) replace it. You can google it "prius see saw coolant valve" and find discussion and some youtubes about it.

[@stlkev]

The noise may be coming from the inverter coolant pump that sits right next to the coolant control valve. It makes a noise just before going out. Check for circulation ripples in the inverter coolant tank.

[@checker7520]

Great video! A natural teacher.

[@lonniejr8047]

Great video and great idea on tubing for vicegrips. I used your tips and it worked great

[@trentquido7287]

Great video and tips! Would you know where to get the coolant cap great cap to use 👍🎉👊

[@wimschoenmakers5463]

Nice but...... Why didn't you started the car and taking care of the fluid level first, before putting the headlight and the others parts back ? If the new waterpump isn't running your back to start. 🤔

[@kenji4861]

Good point. Testing first is important

[@sanman187-]

I watched your video recently, before I took my car (with an Amazon new part) to my repair shop. He replaced the pump but I noticed he didn't disconnect the battery before the replacement. Afterward, the following day, I got a red triangle warning light (with a red exclamation point) when I was driving. It seems to have disappeared now... I hope! Also, he replaced the same part 20 months ago. The reports I've read say my 2008 Prius is prone to coolant control valve problems. Two questions: 1.) why do you disconnect the battery and 2.) do you think that caused the warning light to go off (and is it fixed now??)?

[@EfficientRVer]

Disconnecting the hybrid battery isn't needed, and has nothing to do with your "red triangle of death". When you get the triangle, there is (usually?) a yellow icon on the upper left corner of the screen saying what it is for. On my 05, I've gotten it for two reasons. One is an error with the suspension sensor used to re-aim the headlights based on how much your load is tipping the rear of the car down and headlights up, so the icon shows a headlight with some up/down arrows. The other reason I've gotten it was for engine coolant temp reaching 120C (248F) which I presume is why you got it. You probably were down some coolant after replacing the coolant control valve. BE REALLY CAREFUL to bleed the air out of the system after doing this replacement, or getting a temp warning for any reason. The video is wrong about where to add coolant. You don't just want the overflow tank filled as he showed, you also want to open the radiator cap to your left (toward the passenger side) from there (obviously not first opening it when the engine is hot), and keep topping it up while you run the engine for quite a while and it burps air out. Do that until the cooling fan has cycled on and off 2 or 3 times. Then check it again after driving a bit, and again every day until it stops needing coolant added. If you EVER see the triangle on the dash accompanied by the yellow thermometer icon on the screen, be SUPER CAREFUL to get off the gas pedal completely within a couple of seconds, and stop until the red triangle goes away. With the coolant low, I've seen it only take 5-10 seconds to go from when the light comes on at 120C, until the temp reaches 130C. And that was just driving up a slight hill at 35mph in average weather. On a highway, mountain, or hot day, you could boil over and/or blow the engine in just a few seconds. The Prius normally holds the coolant temp quite close to 90C. Most of your safety margin is already gone by the time the red triangle comes on at 120C. I HIGHLY RECOMMEND that after getting a temp warning, you monitor the exact coolant temp via the ODBII port, until you're sure things are fine again and you are getting no red triangle due to temp. A cheap scan tool dongle ($15ish on eBay/Amazon) with the ELM327 chipset connected to your phone via WiFi or Bluetooth, running the free Torque Lite app or similar, will give you a real-time display of coolant temp. Personally I use a Launch Creader Elite scan tool to show and graph live data like that.

[@ourvdo549]

@@EfficientRVer Thanks for all the helpful tips. The Toyota Factory Shop Manual advises to pull the Hybrid Battery disconnect before any work is attempted under the hood. Just want to be safe!

[@christophern.9234]

@@EfficientRVer I don't think you mentioned loosening the bleeder valve on the radiator. This will allow the air to escape much faster. Just loosen the bleeder valve and put a large funnel filled with coolant and run the car in maintenance mode.

[@gustavojimenez4489]

Thanks for the video, I have problems with my 2007 Prius, the dash light goes out, change the 12 V battery but it remains the same, if I disconnect it for a few minutes it turns the lights back on but now it is more often

[@ourvdo549]

You're welcome Gustavo! I wish I had a solution for your problem. I did have an issue later with this vehicle's dash lights ALL coming on and tripping multiple trouble codes when scanned on the OBDII. This was solved by replacing the Hybrid Battery - I highly recommend Hometown Hybrids out of Houston, TX. Cost about $1k - but they offer a warranty, came to us and had the battery swapped in about an hour and solved all the trouble codes. Not sure this will fix your problem, but you might want to give them a call - 1-844-447-7487. Blessings and best of luck!

[@boobtubeakatv1296]

@@ourvdo549 Somewhere, I heard that pulling that Hybrid Plug in the back would mess up the inverter unless something was disconnected first... I don't remember IF that was the 12 volt Service Battery or not...

[@Colima2012]

Ya trataste de limpiar la conexión que va en el empleador de la batería tal vez se te soluciona

[@hoonetic]

Your combo meter might be the cause. Look it up online.

[@charlyvalentino6226]

Check it connection of the ventilation of the back batteries are always dirty and the water gets into them so it fails sometimes that

[@popoya5549]

I'm having the same problem and what could happen if I don't change it ? Does this turn on check engine light? my check engine light sometimes on sometimes not. Basically check engine light turns on when I press gas pedal on highway

[@RogerPack]

What codes?

[@OkraPlutonium]

Did you put the coolant in the wrong tank?

[@EfficientRVer]

You need to add coolant both to the overflow tank, which he did, and in the real radiator cap to its left, which he did not. Idle the engine through 2 or 3 cycles of the radiator fan coming off, while adding coolant, needed mostly where the real radiator cap is, not the tank.

[@playfullysound4187]

10:27 it slips right out through there nice

[@AKAtareq]

Your video helped tremendously. Thank you

[@JoeZyzyx]

I use a cat box to catch oil and other fluids, LOL. I would check the coolant level again after driving it some, just to be sure.

[@rrodgers3285]

Wow detail video thx so much u rock amigo well c how i do 🙃

[@ourvdo549]

Thyank yoiu! Best of luck to you friend!

[@robertcraft-pj2jp]

Does this valve affect the heater to the heater core?

[@wabfil]

Yes. It controls the flow of hot coolant to the heater core.

[@1FreeSelfGoverningAmericanMan]

I like your Peacocks!

[@ZillaYT]

Definitely easier to do it this way.

[@boobtubeakatv1296]

EXCELLENT JOB !!! I almost feel confident now that I can do this... But, with only clear vision in one eye 😭 it'll take me longer to do... Just follow the sequence 🤩 Definitely an easier way removing the headlight assembly... Hmmm... New HID headlight, blinker and marker lights too 🤪 LED ??? A lot of plastic parts though 😳 I'm also gonna change that inverter coolant pump while it's sitting so exposed 😛 Thank YOU so much !!!!!!! You've earned a subscription 🥳 Very Good Camera Work and description in a concise voice... BUT... 96° & 70% humidity is not an option 😫 The neighbors would laugh at a 🤡 in a speedo 👀🤔🤣🤣🤣 '05 Gen II , 90,000 miles 🥴 Original Owner, 40 to 53 mpg, 50% -70% SOC... I can hear one of them struggling to pump 😱 Squeak, Squeak, Squeak...

[@victorhernandez4241]

Did this give you a red triangle warning or just a check engine light?

[@ourvdo549]

At one point got the red triangle and multiple MIL error codes, then had hybrid battery swapped by Hometown Hybrids in Houston, TX and that cleared all of them. Then a couple weeks later got the P1121 MIL. Hope that helps!

[@RogerPack]

This just gave me check engine.

[@lovebirdslane5545]

Bleed the air out of the coolant...

[@coryfuqua7297]

How do you do that?

[@berber779]

Great

[@Donvonn71]

What is the cooling control valve for is that for the hybrid the converter...

[@mdhsabh]

No. The coolant ("cooling") control valve helps the engine get hot fast, and stay hot when the car is on but sitting still. There's actually a "thermos bottle" behind the driver's side headlight that holds hot water when it's heated up. The coolant control valve routes water between this bottle, the engine and the car heater. The pump at 5:51 in this video that he describes as the "coolant pump" is the inverter coolant pump. The coolant system for the inverter is totally separate from the car engine coolant system. The fluid reservoir for the inverter is the white tank on top of the engine with pink coolant visible thru the side. The car's "water pump", or engine coolant pump, is on the other side of the engine (right side from the driver's perspective), belt-driven thing on the engine.

[@bachelorbob96]

You demonstrated adding pink inverter coolant to the green engine coolant reservoir!

[@jaimichaelmusic]

All coolant in a Prius is pink. Never use green coolantin a Prius!!

[@juanalvarado9599]

My 2001 Prius is not heating in side. When is parking only when is running more then 50mph Someone now watts is the problem???? Thank you

[@hoonetic]

You have air in your coolant lines. You need to bleed the coolant and make sure no air gets trapped in your coolant lines. Check youtube on how to use the pressurized tool to do it or get someone to do it for you.

[@mdhsabh]

The coolant control valve controls where the engine's hot water goes, and whether or not it goes into the heater core. If you have a "check engine" light that came on, go to an Advance Auto and see if they will help you read the code on your car. My guess is that it will indicate a bad coolant control valve position sensor. (I forgot the code, but you can look it up online.) Then, if you need the pump, return the favor and buy it from the Advance Auto that helped you read the code. (Don't bother bleeding your coolant system unless you're certain it's needed; if the problem is this control valve, bleeding is Not needed; just follow the tips in this video.)

[@EfficientRVer]

A 2001 Prius (first generation, in fact first year brought to the USA... I bought a 2001 in 2000) is a rare animal compared to the extremely common 2004-2009 second generation. Almost all advice you'll receive will be from people who have never owned or worked on a 1st gen Prius. Some advice might apply to both generations, some might not. But in almost any car, a heater not heating, does indicate air in the system, a coolant pump problem, a thermostat problem, a coolant valve problem, a heater control problem, a duct control problem, or a blower problem. I wish you luck with the 2001 Prius. It is an amazing car, and Toyota really spared no expense in designing and building it as perfectly as they could. But keeping it alive might turn into an expensive project, as with any low-production antique, which it is getting close to being. Even Prius experts and collectors get a bit scared at the thought of owning one now. I would not mind owning one again, but definitely not as the only car I own.

[@juanalvarado9599]

My problem was the coolant leak and I fixed yet thank you so much

[@JailaniSangari-ci3is]

Hi

[@JailaniSangari-ci3is]

Watssap number

[@automobiletechnically7819]

rs automobile work shope

[@Saa42808]

You didn’t start the car.

[@davesmith5080]

Definitely some confusion in the comments. I agree with mdhsabh. Might rename the title to engine coolant control valve replacement. This control valve is NOT for the inverter coolant system which is completely separate from the engine coolant system. Toyota made it more confusing by putting this control valve right next to the inverter coolant pump mentioned at 5:55. Yes change them both out while the headlight is out of the way. :). Here is another resource for the GEN2 cooling system: chrome-extension://oemmndcbldboiebfnladdacbdfmadadm/automotivetechinfo.com/wp-content/uploads/2020/09/Mastering-the-Toyota-Gen-2-Prius-Engine-Cooling-System.pdf

[@ourvdo549]

Thank you so much for contributing this document! Great resource for all us DIYer's

[@berber779]

Great

[@berber779]

Great

[@berber779]

Great