Inverter pump relay, inverter or other problem

2005 Prius would not start, red triangle of death and yellow triangle followed by orange car symbol with exclamation point in center console. Car would not go into ready mode and would only shift into neutral or park. After repeated attempts it did start but stalled after about 1 minute.

Looking for some advice on what the problem might be. Here is what I checked so.
12V battery was a bit low maybe 11.5 volts - I recharged the battery and under load when re-inserted in the car it was reading about 12.2 volts. When I say under load the electronics booted with the above symbols being displayed and then made use of the center console and associated procedure to use the center console to read battery voltage.

I checked the inverter coolant tank and did not see any vibration of the fluid. Again the computers were booted but the car was not in ready mode. I checked the AM2 fuse both visually and with an ohmeter and it is fine. I did not realize there are two pumps - one for the inverter and the other for coolant thermos. I checked the CHS WP relay and it appears to be defective - this relay is for the coolant thermos. I removed the relay and metered infinite resistance across pins 3 and 5. Subsequently, I applied power (12v) to pins 1 and 2 and measured the resistance across pins 3 and 5: Sometimes infinite resistance and sometimes around 20K ohms. I understand that this is the wrong relay I have been checking if I suspect the inverter, but it seems odd that I could have more than 1 electrical problem.

I have the Haynes guide that presumably covers my model year although the wiring diagrams shown are for 2004 and 2007 - I am guessing I should be looking at the 2004 wiring diagrams? This shows a relay labeled INV WP relay which is a single pole single throw relay. It is wired in series with the Inverter water pump - at least according to the 2004 wiring diagram. I have seen others mention the IGCT relay but I think that may be for different model years.

The problem I have is that the physical diagrams in the Haynes manual I have do not show a INV WP relay in either the engine compartment relay block 2 or engine compartment junction block/relay block (This one has all the fuses and some relays)

My thoughts were since the fuse was OK perhaps the relay is defective, but I have no idea where it is?

Has anyone run into this before?

Much thanks for any replies.

 

Thanks for all the replies. I had the car towed to an independent shop and apparently all my symptoms were the results of a bad hybrid battery P0AA6 with subcodes 526 612. The good news was I still had full replacement warranty on the battery so I got a free replacement. Some things that I don't understand though, according to my testing the CHS WP relay was bad - but it's possible someone had posted incorrect information - not from this forum elsewhere.

But yes working blind w/o a code reader is a waste of time.