How many water pumps in 2005 Prius.

Yes, of course they are kindly offering you another walletdectomy.

To my knowledge, the coolant heat storage pump doesn't sound like "woo- woo, woo-woo". It's more of a continuous screech.

It would be helpful if you could record the noise and upload it for us. Someone might be able to tell you what you're hearing.

 

More likely a wallestomy. You keep your wallet, but now it has a hole for continuous drainage

 

Gen 2 North American Prius does have 4 water pumps.

-Inverter water pump you listed it as HV Electric Water Pump (it runs always when Prius is powered on to cool all hv-electric parts except the battery)
-Engine Water Pump belt driven pump (runs when engine is running to cool it and to heat up interior)
-Coolant Heat Storage Water Pump it pumps coolant in and out of heat storage tank (normally runs at startup and shutdown)
-Heater water pump it pumps hot coolant to heat interior if engine isn’t running but is warm and heater is used (runs if engine isn’t running but is warm and heater is used)

 

From the service manual:

The heater water pump sends engine coolant to the heater core while the engine is stopped to prevent heater effectiveness from becoming low. Directed by the air conditioning amplifier, hybrid control ECU operates the water pump relay and drives the heater water pump.

 

My pump makes a tea kettle woo woo woo sound too. Normally when i shut down. I've been ignoring it and now oblivious to the sound.

 

Yes, what you paid to replace the engine coolant pump is high. That is normal business practice for a dealer service department.

Regarding the coolant heat recovery system pump, as long as it is working (which it is, if you don't see the check engine light appear) then don't worry about it - unless you are the kind of person who is OK with spending $475 to deal with a minor noise that has no impact on functionality and only appears for a few seconds.

BTW, if you are counting all pumps that move a water-like liquid, don't forget the windshield washer fluid pump and the back hatch fluid pump...

 

I haven't done the Coolant Heat Storage Water Pump, so I don't know how difficult it is, but the engine water pump is very easy. its a diy if you have any mechanical skills at all. and a 10mm socket...
bleeding the coolant system does take some time because air gets trapped in the system. but it'll save you about $400 bucks.

 

Today, I got P2601 code for my 2008 Prius. Per my internet research, it seems related to the CHSR system pump. But as I searched entire internet, using the key words of "Prius CHSR pump", all results came with the inverter coolant pump, which is HV electric (12V) water pump. Does 2008 prius really have 4 pumps? May someone point me some direction where to find the CHSR system pump? Thanks.

 

You can try CHRS instead, for coolant heat recovery system. If you're having problems finding something on it, it may be because it's a rare repair.

 

Thanks. I found the information that there are four pumps. The reason that I got confused was that I thought the CHRS pump was in the inverter coolant loop because the CHRS tank is located just below the inverter coolant expansion tank. But this pump is actually hooked up with the engine coolant loop.

 

Update: Following some posts here, I tested the voltage from the terminals after pulling out the CHRS pump relay. No voltage was detected. Then I checked all the fuses in the fuse box and all of them were good. Measured the voltage again, still no value. So I gave up after I erased the code using a scanner. Since then, I have driving the car for about 250 miles without any difference and with great gas mileage (48 on HW and 54 on city). No any code comes back yet. Just checked the I/M readiness, found that all were ready but the EVAP.

 

Terminal 3 on the CHRS relay, the top terminal (fed by a green wire), must have 12 V on it at all times when measured to chassis ground. If not, the fuse labeled 10A CHS W/P is blown. It's in the fuse holder in the engine compartment. Don't rely on a visual inspection, use an ohmmeter.