Help replacing a coolant pump

[Lido]

I'm hoping to replace the "left" coolant pump as mentioned here and was wondering if anyone who's done it already could give me a few pointers or maybe answer a few questions.

Do I need to take the plastic cover off of the center area under the hood to access things? I've seen pictures of the replacement pump and I can't actually see it under the hood anywhere.

Should I drain all the coolant before starting this or do you somehow plug the hoses?

Do I need to disconnect either the 12v or the main battery before starting to avoid shocks?

From these questions, does it sounds like I should just have a shop do this?

Thanks!

 

[fred_dot_u]

I've replaced the right pump and prior to squeezing off the clamps, I used scissor-like glue clamps to flatten the hoses to prevent leaking. I didn't worry about the battery, because when the power and control cable is disconnected, there are no exposed contacts. I just popped the hood and tried to find a left pump but failed. There's a "center" pump that is certainly going to be left of the right pump, but is it the left pump?

Once you find it, I suspect you'll discover that replacement isn't particularly difficult. The right and center pumps are simple bolt-on modules, with the right one being only slightly more challenging than the center.

It's been said that when one opens the cooling circuit in this manner that one should ensure to purge all air from the lines. In my case, I noted that the level in the reservoir dropped not below the bottom of the tank and when refilled and operated, dropped a small amount more. Vlad performed a purge but the level didn't change, leading me to believe that no appreciable amount of air had entered the system.

 

[Lido]

I don't know what I'm looking for at all. Are either of these what I'm looking for? And if so, do you know if either of these is the Number 1 pump? "Left" is pretty ambiguous depending on where you're standing, but "left pump" is what the dealer told me the error was.

 

[alflash]

View attachment 85

I don't know what I'm looking for at all. Are either of these what I'm looking for? And if so, do you know if either of these is the Number 1 pump? "Left" is pretty ambiguous depending on where you're standing, but "left pump" is what the dealer told me the error was.

Take a look location for bad pump of your vehicle (orang.)

https://alflash.com.ua/2019/to_rav4ev/bat_cool4.png

 

[fred_dot_u]

The number 2 pump assembly is the easy one. I'm not sure why the dealer would call either one of them the "left" pump, as it's typical to reference position by the motor vehicle operator perspective. If your left turn signal is out, it's not when you're facing the car! With the diagram in mind, I visited my vehicle again and was not able to find the pump from above and my limited flexibility precludes getting under and looking up. I would also expect that the same panel that covers the speed sensor on the motor will block access to the pump. It's easily removed, however.

 

[Lido]

Makes sense. Is the big plastic cover in the middle the panel you mean that should be removed? @alflash is the orange outline in my photo corresponding to the orange outline in your diagram or do I have the wrong thing identified? Thanks!

 

[asavage]

The pump you circled in orange is the Cabin Heater pump.
The pump you're searching for is NOT under the decorative "TOYOTA EV" plastic cover; it's lower, on the driver's side.

[later]
Everything I wrote above is wrong.
The cabin heater is the left one in Lido's pic. I could've sworn the colors of the outlines were reversed from what I see now; my mistake.

 

[asavage]

The service manual chapter on R&R the left coolant pump is removed from underneath the vehicle:

• REMOVE DC/DC CONVERTER COVER ASSEMBLY RH (the big plastic decorative "TOYOTA EV" cover)
• REMOVE UPPER NO. 1 FLOOR BOARD (this means the front underbody plastic cover)
• DRAIN COOLANT for HV Battery
• [ . . . remove the RH pump . . . ]
• REMOVE WATER PUMP WITH MOTOR LH

Screenshots:

 

[asavage]

Screenshot from the above Service Manual page shows the RH pump (sorry, the low-res image is the only one I have):



I just jacked mine up and took a couple of pics, from the RF wheelwell, behind the tire, and there's the RH pump:









Removing the plastic underbody panel would undoubtedly be the easy way to access the RH pump for replacement, but there's enough room to slide my phone behind the RF wheel to take those pics.

Here's the LH pump image from the Service Manual, showing from above, implying that you can access it without taking off the underbody panel:



So, as I don't have the top cover "TOYOTA EV" installed (ever) on mine, it was fairly easy to take some top pics:





It doesn't look to be a lot of fun, though. Of the four electric coolant pumps, this has the poorest access. I have a remote clamp tool that would possibly be helpful, but access is still fairly tight (search for "Mayhew" in this long post).

---

I happen to have a Model S coolant pump on my bench (for over a year!), and this is what it looks like:

 

[Lido]

Wow, thank you for all the detail and photos! Getting under the car isn't something I'm up for at this point. I'll probably try to find a local shop that's willing to tackle it.

 

[asavage]

I had made several revisions above; you may have read one before I noted that it appears to be a job done from the top, but not "easy", or at least not as easy as the Cabin Heater pump or the Traction Motor pump, which are both easily visible and don't require contortions or laying down on a platform to access the LH pump behind the DC-DC Converter/in front of the firewall.

The Service Manual section I screenshotted covers R&R of both LH & RH pumps; the advice to remove the underbody panel looks to be required only for the RH pump, and for cleanup/coolant recovery purposes, but since that cover comes off easily (except a couple of the retaining clips "always" break or somehow don't get reinstalled), if the car is on a lift it's easy to R&R the cover, and keep the spilled coolant mess to a minimum.

Yeah, having a shop do it for you is always a nice option -- if you can find one that will take it on. Most conventional shops steer clear of EVs so far. When shopping for a shop, be sure to tell them that you need a 12v coolant pump replaced, and that it's standalone (not bolted into an assembly). That will reassure them that it has nothing to do with high voltage or specialty assemblies.

It's just a couple of hoses and one electrical connector; the hard part is where it's located.

 

[alflash]

The pump you circled in orange is the Cabin Heater pump.
The pump you're searching for is NOT under the decorative "TOYOTA EV" plastic cover; it's lower, on the driver's side.

Dear Sir,

This figure https://alflash.com.ua/2019/to_rav4ev/bat_cool4.png from the Toyota training shows the location of two pumps that service the HV battery.
Why do you call one of them (orang) a cabin heater pump and mislead others - I don't know.

Note to readers of this topic.

1. The diagnostic program and DTC description don't use the terms “left or right” pump.
Their terminology is like this
https://alflash.com.ua/2019/to_rav4ev/thc_d0004_0005_0006.png

2. Since pump number 1 is located to the left of pump number 2, those terms are sometimes used that call is by their location along the drive of the vehicle.

3. The heater pump has a different design and is located as shown in this screenshot from the repair manual https://alflash.com.ua/2019/to_rav4ev/heater_pump.jpg

Hope this will be useful for to eliminate/avoid misunderstandings.

A copy of the current state of this topic has been saved.

 

[alflash]

@alflash ... is the orange outline in my photo corresponding to the orange outline in your diagram or do I have the wrong thing identified? Thanks!

Absolutely not. In your photo the engine cooling pump is marked in orange.
In my picture the faulty HV battery pump is marked in orange.
As I see you circled the engine cooling pump

https://alflash.com.ua/2019/to_rav4ev/motor_cool_pump.png

If your vehicle was read the year of DTC THC_d0005 Battery Coolant Pump 1 Malfunction, then the location of this pump, which some call the left one, is shown in this image
https://alflash.com.ua/2019/to_rav4ev/bat_cool4.png

Perhaps someone will be interested in this video of checking the controllability of the cooling pump


p.s. During checks by dealer technicians, did they check the fuse and the 12V power supply relay for this pump?

 

[Lido]

p.s. During checks by dealer technicians, did they check the fuse and the 12V power supply relay for this pump?

Tustin (California) Toyota Dealer's service department did the diagnosis. They didn't give much detail beyond what I posted in the other thread. If the fuse is accessible, I think that's something I could check with a meter. Not sure on the relay. Any help would be appreciated. Thank you.

 

[Lido]

Most conventional shops steer clear of EVs so far. When shopping for a shop, be sure to tell them that you need a 12v coolant pump replaced, and that it's standalone (not bolted into an assembly). That will reassure them that it has nothing to do with high voltage or specialty assemblies.

Thanks, I'm going to search for someone locally that handles at least some EVs before maybe trying a shop that advertises hybrid servicing.

 

[alflash]

Tustin (California) Toyota Dealer's service department did the diagnosis. They didn't give much detail beyond what I posted in the other thread. If the fuse is accessible, I think that's something I could check with a meter. Not sure on the relay. Any help would be appreciated. Thank you.

1. Location of battery pump fuses
https://alflash.com.ua/2019/to_rav4ev/pimp_fuse.jpg

2. Give dealer employees this list of mandatory checks when reading the code THC_d0005 Battery Coolant Pump 1 Malfunction
https://alflash.com.ua/2019/to_rav4ev/THC_d0005THC_d0006.pdf.
Perhaps he is terra incognito for them

3. Another drawing of the location of the faulty pump in your vehicle
https://alflash.com.ua/2019/to_rav4ev/COOL_LOCATION.png

4. Any adequate car mechanic is able to repair this faulty pump while observing the following safety rules
https://alflash.com.ua/2019/to_rav4ev/__precaution.pdf
https://alflash.com.ua/2019/to_rav4ev/__PRECAUTION2.pdf
and such instructions
https://alflash.com.ua/2019/to_rav4ev/REMOVAL_PUMP_WITH_MOTOR_(forHVBattery).pdf
and the previous drawing of the location of the HV battery pumps
https://alflash.com.ua/2019/to_rav4ev/bat_cool4.png

5. Let me remind the standard time for replacing the battery pump
https://alflash.com.ua/2019/to_rav4ev/flat_labor.png
I wonder why they wanted to get 2 thousand dollars from you...
Even if buy at a price for idiots at
https://autoparts.toyota.com/products/product/pump-assy-water-w-m-g90200r020,
it’s all the same there will be a much smaller amount.

HTH and best regards.

 

[Lido]

Thanks for this. Are the fuses the hard to access ones under a nest of stuff that was mentioned in another thread or are these somewhere I can easily access to test/replace? In other words, where can I find that box with the fuses in your image "
1. Location of battery pump fuses
https://alflash.com.ua/2019/to_rav4ev/pimp_fuse.jpg
"?

Thank you!

 

[alflash]

Surely the fuse is intact and serviceable, but you must make sure of this

Look under the hood this box
https://alflash.com.ua/2019/to_rav4ev/motor_compartment_left.jpg