New inverter coolant pump not working

There are a few iterations of this pump more than likely I can't imagine it wouldn't have changed in the last near 20 years. There are other pumps that can do this duty and wire in without issue probably 30 of them they're not Toyota branded or anything like that but they are for hot water duty and made for other applications I'm using a few of them in other cars similar type of situation. The fuse that would blow when the inverter pump is not working creates other issues You would know it I think it's AM2 or something like that then there's a connector right above the fuse box it's black If you follow that connection down to the pump you'll see that's an auxiliary plug to unplug the inverter pump without having to try and reach the actual inverter pump but other than that I don't think there's anything else that safeties or supplies power to that pump It is very common for cheap aftermarkets to work a few minutes and then never again If they were to make a few months that would almost be a miracle the cheap copies that is I don't know why that is It's a cheap pump to begin with how you could cheapen it more and make it fail instantaneously is beyond me somebody must be working really hard to make that happen and why?

 

According to my wiring diagram,

Looks like the fuse is IGCT No.3

On the inverter water pump :

Pin1 : Ground (white/black)
Pin 2: NWP (pink)
Pin 3: SWP (green)
Pin4: Power (light blue)

I'm guessing the NWP and SWP are a pulse width control and a RPM monitor, not sure which is which.

Was the old pump not working either? Did the codes come from the old pump?

I would return it anyways as it's a terrible idea to have an eBay water pump in your car. Assume everything on eBay is counterfeit because it probably is.

 

Yeah usually you can unplug the inverter water pump up on top of the fuse box as a black plug then you can probe with your red terminal from your volt meter and your black one on standard ground and see if when the car's ready and on you have 12 volts and one of those I don't know two or three wires that go to the inverter pump as you do that's probably the one that when you turn the car off the 12 volt goes away so you know you've got 12 volts going to the pump it should be vibrating and doing something It's not I would assume it's broken no need to worry about pulse with modulation and all this other stuff because every time you have your car ready and open the door and all this and that on one of these cars that pump is running your car it's not I would say generally it's the pump that has the problem not usually the car especially if AM2 and the other fuses are in order then you're generally looking at a pump that's either an original that's gone bad from age or a cheap aftermarket that's been in there anywhere from 5 to 50 days Very common.

 

Wait a minute underneath this is a generation 2 I didn't even look to see I can't tell unless I look at the top of the post but you shouldn't need to do anything You just you leave the gold bracket in the car All you want to do is remove the pump so you squeeze off the fittings with some squeeze pliers that lock so the coolant stays where it's supposed to and you just pull the hoses off undo the electrical connection with your long needle nose 45 angle pliers that's Walmart stuff. And then you undo the three gold bolts that are holding the pump to the bracket withdraw the pump with one hand no need to move anything out of the way practically and then take your new pump and undo the gold bolts and get rid of the bracket and drop your new pump on the old bracket connect the hoses top off the fluid and roll this should take all the 38 minutes on a bad day.

 

Of course this is a generation 3 so yep all of that Not a good day for that.

 

You’re doing pretty damn good for an octogenarian.

 

Out of my depth, but does this pump cycle on/off depending on inverter coolant temp? If so, maybe just not past threshold temp?

 

NWP is the pump's tachometer output. SWP is the speed control signal to the pump, encoded as pulse width. The scheme is like that of the engine water pump, described here, where the requested speed is as the % of time at the high logic level. (I typed that all out because, if I remember right, there are also some other variable-speed motors in the car—battery fan?—where that's inverted, and the speed goes as the % of time the signal is low.)

Gen 1 and 2 had a simple pump that was just ON whenever the car was. Gen 3 has a pump that is controlled according to demand and, as described above, it doesn't even just cycle; it's variable speed.

 

Did you get the P0A93 and P0C73 codes before you changed out the original pump?

 

"Permanent" codes are nothing but codes the system remembers it had once as current codes.

It will hang on to permanent codes for a while until it convinces itself the respective conditions have been fixed.

"A while" means long enough for you to have done the right kind of driving to test the conditions in question, and for the tests to have passed, in a few consecutive trips. "The right kind of driving" is different for different trouble codes, and depends on what driving conditions are needed for the car to be able to prove the detected condition no longer exists.

If you get impatient, each trouble code has its own section in the repair manual, and each one has a "confirmation driving pattern" in it, and if you drive exactly that, you can get the permanent code to go away sooner than it would on its own.

Otherwise, you just drive the car and wait for the permanent codes to go away. As long as there are no 'current' codes, the car is working; having 'permanent' codes on record is only an issue if you have inspections, and the inspector wants you to come back when they're gone.

About the only time you'd want to fuss with confirmation driving patterns would be if you have a mandatory inspection coming up with a deadline to soon to just wait till the permanent codes go away.

As one example, if you're too impatient to drive hundreds of miles, P0A80's confirmation driving pattern involves no more than five minutes of driving. The test mostly looks to see how the battery performs in an unusually deep discharge.

 

Does that explain why you're getting the Check Hybrid System display though? Doesn't that infer that you have a current code?

 

Yes, a warning light means there's a current trouble code somewhere.

It's not uncommon for someone to use a scan tool that doesn't find all of the codes in the car.

The gen 2 forum has a thread comparing scan tools and which ones read all the codes in gen 2:

Gen2 OBD2 app review | PriusChat

We don't have exactly such a thread for gen 3, but the good gen 2 recommendations are probably worth looking at.