Information on Steering and Hybrid Coolant Pump Recalls C0T and C0U

Dealer I take my car to called last week, said they had the parts in. Took the car in Tuesday, took all of about an hour to change the water pump, part of the shaft and 3 bolts. From what he said there's a couple of designs, some take longer than others. Not sure if he was correct on this, but I was surprised it was only an hour or so for the work.

 

I just had my coolant pump and steering column remedied.

 

Had mine fixed last week also.

 

My car was in for recall today. They replaced the hybrid water pump and replaced a bolt on the steering shaft. Are the invertor pump and hybrid water pump two different names for the same part? Thanks

 

Yes, both names mean the same part.

 

Got the two recalls done today. They changed one bolt in the steering column, and changed the inverter pump. I am not sure if they changed the inverter fluid or just topped it off. I do note that the fluid is a pretty pink in comparison to what was in there. It seemed to be a little darker tint before the pump was changed. I also note that there is a dramatic difference in the flow of the new pump. With the old pump, the fluid level was less than 1/8" front to back when the pump was running. With the new one, it is about a 1/4 of an inch now and the turbulence is much more dramatic. Also the new pump is a lot quieter. The steering wheel came back perfectly flat. When I took it in, it was off to the left about three degrees.

No crazy lights on dash, and everything seems to be in order. Thank you Fred Haas Toyota in Houston! FWIW, I used to use Tejas Toyota in Humble when I had to go to the stealer, but recently switched to Fred Haas. I think I will stick with them for a while. I noticed quite a difference in the service bays, attitudes of personel and the volume of work.

 

I had both repairs done a couple weeks ago. When I left I noticed the steering was out of alignment from the steering column fix. They fixed it right away, but just something to look for.

 

Not sure how my pump sounded before the recall change but now I hear a low volume whine when I open the hood to see if the fluid is moving. I don't think I can hear this inside the cabin though.The fluid is moving with the cap off so I can see it and feel the hose by the pump vibrating.
Does this pump run all the time in ready mode? After a short trip home today, the fluid was still very cool on the finger. When I shut the system off and restarted, the pump was quiet, I guess not running yet. I am hoping that this is all normal and the dealer bled the system properly.

 

Yes, the inverter pump should be running all of the time while the Prius is in "Ready Mode". I do not believe it run's if the Prius is in "Accessory Mode".

You should be able to see turbulence in the reservoir when the Prius is in "Ready Mode".

 

I am positive to have experienced water pump issues that might be the cause of occasional sudden stalls. I don't have codes to offer yet but I'm working on getting them.

Incidentally, I would have thought that the NHTSA Campaign ID Number 12V-536 (a/k/a 12V536000?) was relevant to my second hand Prius. If my understanding is correct, NHTSA recalls are mandatory (i.e. are not to expire nor to be dealer discretionary), however, I went on Lookup Safety Recalls & Service Campaigns, entered my VIN and my car had no recalls, either pending nor completed. I found that weird.

I researched some of my vehicle symptoms here on PriusChat and my impression (w/o immediate access to DTC codes) was that the issues were 100% water pump related. I then asked perplexity.ai the following prompt: "if the Engine Water Pump And Coolant Control of a prius 2nd gen fails what are the symptoms?" and it displayed the following list of items which immediately clicked with my experience:

1. Overheating: The engine temperature may rise quickly, potentially triggering warning lights on the dashboard.
2. Dashboard warning lights: Multiple warning lights may illuminate simultaneously, including the red triangle, ABS, and check engine lights
3. Intermittent operation: The car may run normally for a short time (5-10 minutes) before overheating and displaying warning lights
4. Unusual startup behavior: The car may only "half" turn on initially, with the dashboard fully lit and the ready light appearing orange instead of green.
   
5. Air conditioning issues: When the dashboard lights up, the AC may suddenly start blowing hot air
6. No warning before failure: Some users report experiencing a sudden failure without any prior warning signs
7. Difficulty starting: The car may have trouble entering "Ready" mode or may require multiple attempts to start
   
8. Low coolant levels: You may notice the coolant reservoir is low, even after refilling
9. Engine cutting out: In severe cases, the engine may suddenly shut off while driving
10. Reduced performance: The vehicle may experience a loss of power or reduced acceleration capabilities.

 

Incidentally, I have huge trust issues with mechanics. I relayed to a "trusted shop" the A/C symptoms listed within the list above and they were very eager to want to test everything A/C related and make me spend a trillion dollars in putting freeon in the system and checking for leaks despite the fact I relayed to them the A/C would work perfectly for two hours or more at a time in the morning and if the car would not be running for 15 or 30 minutes the A/C would cool off perfectly again and will turn my car into an igloo. It turns out their mechanics are paid a commission for all repairs rather than a set wage, so there are great incentives to diagnose the most expensive plausible item they could come up with. I'm no mechanic and trust no one's intentions, so I guess I'm screwed.

I then learned too late, that the symptoms above could be caused by the failure of 16670-21010 or the failure of G9020-47031. By that time I've already purchased an "Electric Inverter Water Pump for Toyota Prius Hybrid 1.5L G9020-47031 2004-2009" for $25 brand new. Will DTC codes tell me if the failure requires the replacement of G9020-47031 vs the replacement of 16670-21010? Are both replacement labor costs about the same? Or could the issue be due to having to replace this part: AISIN Water Pump WPT-190 ZVW30 ZVW35 161A0-29015 TOYOTA Genuine Prius ($137 on e-bay). So any of these (three parts?) could trigger the symptoms above? Will DTC codes allow me to make a distinction that will point to the right replacement? What should I expect to pay in labor in FL for any of these (three?) replacements scenarios? Can Joe Schmoe do any of these three jobs? I saw a couple of Youtube videos in which the entire process for one of the parts was barely like 10 minutes).

Thanks in advance for any advice on this. I thought to take the car to Toyota in order to get the water pump replaced based on that recall. That'll be ideal I'd think as it would be free.

 

Your symptoms could be the result of a failed inverter coolant pump. Power the car on and look in the inverter coolant reservoir for turbulence.

$25 ebay pumps are counterfeit garbage. Aftermarket pumps are questionable as well. The most reliable are genuine Toyota from a dealer.

Get a scantool. The autel AP200 is good function for price. You should find a P0A93 code in the Hybrid Control ecu.

Most of the TSB's from Toyota (like the inverter pump) are handled as "warranty extensions" that are good for 10 years from the original purchase date - period.

Posted via the PriusChat mobile app.

 

Along with what was just mentioned in post 52, please get prices from more than one dealer for the part. There's one dealer in our town that thinks everything is made of gold and their inverter cooling water pumps are $80 more than the dealer 6 miles down the road.

 

I read a thread here on OBDII scanners and there were so many options I felt overwhelmed. For someone obsessed with making the best possible choice this has been paralyzing. I bought a mini VCA a couple of years ago that had some versions of TS in it but doing the laptop thing here in this scorching hot weather isn't much of an option. I'm hoping for an afternoon when I'm not at work after it rained or whatever to get there with this laptop running XP. Got it just for this. (If I can figure out where is at after I moved). I was able to arrange a vehicle inspection at the dealer for the 8th of this month though.

I have done so when shopping for parts. Not sure why there's some sort of wild range of prices in the same exact parts across dealers across the country.

Thank you for your responses!

Ed

 

For the benefit of readers who haven't got microfiche for eyes, G9020-47031 is the water pump that cools the inverter and transaxle. It is not a water pump for the engine. Its name on an official Toyota parts site is "Water Pump Assembly with Motor & Bracket". Its name on some other internet sites might have the word 'engine' in it, like "Engine Electric Inverter Cooler Water Pump Assembly", and that's because many internet sites are wrong.

This inverter cooling pump can indeed be the cause of the A/C symptoms described, because the inverter powers the A/C compressor, and when the inverter overheats, it stops doing that, for self-protection.

That other part number, 16670-21010, is the coolant flow control valve in the engine coolant loop, used to help the engine warm up faster through use of the thermos behind the fender. It has nothing to do with the inverter cooling loop or the A/C, and I can think of no way it would cause the symptoms reported here. (In cold weather, it can cause a no-heat situation, because if it gets stuck in the to/from-thermos position, there's no flow to the heater then.)