URGENT: Stranded with ! PS Battery Engine All on 2001 Prius

Hmm that's a good question, I'm not sure. Guys, chime in here.

 

How are you going to get the part to another shop? Not with your prius.

 

Hi Kristy,

My "how to" relates to 2G Prius (2004-2009 model years.) You cannot use that pump on your Classic Prius. I recommend you rely upon the part number provided by your local dealer.

I would also encourage you not to underestimate the difficulty involved in purging the Classic inverter coolant loop of air. This task when performed on a Classic is much more difficult than 2G. You may need to spend 2-3 hours just working on getting air out of the coolant loop system, lacking vacuum assist devices.

 

If you don't see the higher level in the front, that is not good. The inverter coolant pump should sound like an aquarium pump, when it is working properly and circulating fluid. I am not sure what the vibration signifies.

The coolant is supposed to be replaced at 30K mile intervals unless pink Toyota Super Long Life Coolant was installed, in that case the service interval is 50K miles. I understand your car has logged 110K miles, has the inverter coolant ever been replaced? If not it is possible that a clogged system is part of the problem which may require inverter replacement since the channels are quite narrow.

The inverter coolant pump is not subject to high voltage so that safety issue should not be a concern. An independent mechanic ideally will have access to Toyota repair manual info at techinfo.toyota.com so s/he can research the inverter coolant pump procedure.

A professional will have access to an Airlift system or equivalent, which uses compressed air to help quickly purge air out of auto cooling systems. Here is an example, just for your info:
Amazon.com: UView 550000 Airlift Cooling System Leak Checker and Airlock Purge Tool Kit: Automotive

Yes, but I would not buy that particular one since the donor vehicle logged substantial miles (88K miles) and the price is relatively high compared to new.

 

See my prior post regarding the possibility of inverter cooling channel clogging, if the coolant was not regularly drained and replaced.

 

The inverter would eventually overheat if the cooling channels were clogged.

We don't know what DTC were logged by your car. Therefore I cannot say whether an overheated inverter caused the driveability issues and warning lights that you experienced.

I don't think it will be easy for a mechanic to determine that the inverter cooling passages are clogged. I suppose the first step might be to see whether the original pump can move fluid or not.

 

Would it be this. this looks like an updated model. Im sure it can be found cheaper.

2001-2001 Toyota Prius Water Pump - OES Genuine W0133-1910622

 

I'll endorse all that Patrick has posted but wanted to add one thing about the NHW20 (2004-09) and NHW11 (2001-03) inverter pump. Both have essentially the same pump housing but the base is different. The housing is important because there are two pins, B+ and Ground, on the NHW11 in a specialized, custom connector. I never bought an NHW20 inverter pump to test whether or not it would fit as I already have my 'spare' inverter pump.

We know from Good Prius Friend Hobbit's posting that one inverter he disassembled had 'jelly-like' substance in the cooling channels. We know some aluminum salts can form jells and this has been suspect in other incidents. When the coolant is drained, please collect it in a clean pan and pour it into empty, clean water bottle. I would like that coolant IF there is evidence of jell-like material for chemical analysis.

This is my spare inverter pump connected to hoses and running:


This is my spare ZVW30 (2010-current) inverter pump that I bought to see IF it could even fit:


The 1.8L inverter pump is much larger. You can also see the custom, socket built into the original pump housing, two wires, on the left. The ZVW30 pump has four wires in a larger socket, on the lower right.


Head on the outlet tube, even the pumbing is different:


I got an old inverter pump that the owner attempted to disassemble with a hammer. I used Dremel tool to remove the pump housing and you can see the impeller has broken blade . . . possibly from the first attempt:


Here you can see the hammer cracket the solid case and the impeller blades broken:

The impeller has a ceramic insert that rides on a polished, steel pin. I could not see any obvious reasons for the original pump failure and there was not a lot of 'wobble.'

Another view showing the impeller and steel shaft:


Another view showing the impeller mounting:

The rim of the impeller assembly to the right shows the embedded magnetic material. Coils in the body are operated by a circuit board, embedded in the flat part of the inverter pump.

Now if it is New Years Day and I am stuck, I would be tempted:

• practice removal of the pump - drain the inverter coolant into a clean pan (inspecting for jell-like clumps). Then remove the pump since there are clamps and fasteners that need to be dealt with.
• test removed pump - using the first photo showing the B+ and Gnd, apply 12 V and verify the pump 'runs'. I would have a pan of water handy and stick the center, inlet into the pan and see if if sucks and spews water. If it does, use a water hose and nipple to verify water flows through both the intake and outlet hoses. This may require some creative 'pumbing' at a Lowes or hardware store (where I got my hose for testing.)
  • If there is evidence of a jell-like blockage that presure water clears, reassemble, fill and flush with distilled water. Considering the sub-freezing weather on the way to California, I would consider using a cheap coolant to get home (and flush) and have my home mechanic replace the pump and coolant.
• install replacement pump and coolant - bleeding is as much an art as practice but one trick after doing as much as possible, carry some spare coolant and at 5 miles, stop and top-off resevoir; at 15 miles, stop and top-off; at 50 miles, stop and top-off, and; 100 miles. Then check at each fill-up.

Now what I've outlined is what I would do but I have manuals, tools and self-confidence. I also have three NHW11 OBD scanners that can be used to read out the codes to confirm the diagnosis. But absence of coolant flow is the signature of an inverter coolant pump failure BUT we can not rule out blockage from jelled coolant.

Bob Wilson

ps. I'm sending you a private note with details but I will offer you this deal: (1) pay-pal a deposit for a scanner and spare pump, overnight shipping (your choice of carrier), and (2) I'll express ship the part with tracking number to your parent's residence, and (3) refund the non-expense part of the deposit upon return of scanner, failed pump (if so diagnosed), and coolant sample (if it has jelly-like material in it.)

 

Bob's offered excellent advice as well as a kind offer that will help should the OP choose to either DIY or use an independent mechanic.

The Prius diagnostic system will not distinguish between inverter overheating caused by

1) a pump failure vs.
2) a cooling channel clog.

If the Prius can be made READY and driven (for a short distance) without warning lights coming on, then the inverter electronics should still be OK. However, if in fact cooling channel clogging is present, then the inverter will need to be replaced regardless.

Therefore some investigation and thinking will be required of whomever is going to work on the car, to ensure a happy outcome.

 

The part number for the correct pump for Gen1 Prius is G9020-47022. Although I have not seen the Kristys car, based on the (dozens of) Gen1's I've seen I would say there's an 90% chance the pump is bad and 10% chance the cooling channels are blocked. I always have a new pump in my Boulder shop, but I'm over 500 miles away from where the car is sitting.

Also, someone said "dont' drive the car until you fix it". If weather is cold you should be ok for short trips...(like across town to a better mechanic). You may have actually driven from California with no pump and not done any damage to the inverter.

 

Clogged inverter channels are a risk but draining may get the 'crap out.' With the testing hose, she or her mechanic may be able to arrange a 'power flush' using common hardware parts. It is likely to be 'splashy' but that is what I would do.

The only thing I didn't include are those screw-on host clamps used to seal the 1/2" test hose. I just don't have any handy and I've already boxed everything up:

The approach I would take is open the box, look at the instructions and decide 'can I do this or do we get a mechanic or volunteer to help?' (NOTE: an independent radiator shop MIGHT be willing to do the work and is most likely equipped with 'flush' equipment. . . . negotiate.)

Do-it-yourself, will need that big metric drain nut (wrench or socket) and metric sockets to handle removal and install. I would first connect the Graham miniscanner and read out the error codes (just turn on to ignition and use the diagnostic menu.) Write down the codes found and clear them. Then turn off the car; go to ignition; start the Graham miniscanner, and; start the car. Using the pre-programmed data, navigate to slot 6 that has the inverter temperatures. If they climb to +50C, watch them closer. If they reach 80C, turn off the car, the inverter is starting to overheat.

Drain coolant into a clean pan. If 'chunks' or 'globs' are observed, I want samples for more detailed analysis.

Once access to the existing pump is made, the hose can be used to see if it is working or 'just vibrating.' With plumbing fixtures, blow air or water through the hoses to make sure the channels are clear. If an obstruction is found and normal plumbing techniques are able to flush the channels and the existing pump is working, I would close everything up, refill with coolant, bleed the air, and plan to drive home . . . with the kit in the car and tools.

If the old pump is just 'vibrating', swap with replacement pump (may require some trickery to get base seated), seal everything up and put in coolant, bleed the air, and plan to 'modestly' drive home . . . with tools and failed pump. Frequent stops on the way back to check the inverter coolant level and top off if it 'burps' any more air.

Get home and at your leisure, negotiate an inverter pump replacement with the newest model, coolant drain and refill, and return to me the good stuff I want back and/or failed parts and coolant sample IF there is any 'jell' or strange stuff.

Can anyone think of any other changes or ideas?

Bob Wilson

 

Whoever works on the car needs to drain only the COOLANT, 24mm drain plug on silver part of the bottom center of the transaxle which is on the drivers side of the car. Don't drain the transmission fluid. The ATF is the exact same 24mm drain plug but the ATF drain plug is on the transaxle black oil pan. It can be confusing. DO NOT OPEN THE PLUG ON THE BLACK OIL PAN (unless you want to change the ATF as well).

You may be able to borrow a code reader/scanner from Autozone or similar parts store open today and see if the generic scanner picks up any valid codes. Post the codes here.

Try and get new coolant from the dealer.
The RED Toyota coolant should be mixed 50/50 with distilled water. (what car had from the factory).
You can also use the PINK Toyota coolant which is already diluted.

 

3prongpaul, That was me that said to not drive it until she fixes it. I was saying that based on what I would do. I myself would be afraid I would burn up the inverter. if the inverters on these are capable of handling short trips, that helps her out on getting this thing to someone to get it fixed without a tow truck