2003 Prius won’t start

If his HV battery is at 0%, it won't start. And probably the battery is no longer among the living. They don't like being completely depleted. And charging without a grid charger is problematic. I understand the individual modules can be charged, but it's a lot of work and probably won't save the battery. Would be nice if you could borrow a grid charger and a pigtail. Time for a replacement battery--which may not be economically feasible.

 

I did run the Toyota techstream software on his car and noticed that his SOC % for the hv battery was at 0% so that may be the problem.

Sounds like a great place to start............On another note, it's pretty hard (but not impossible) for a HV Battery to really be at zero soc. Check the voltage and see where it's at. Keep in mind normal is 280-290ish for a Gen 1. If it's around 265 or less, it's either severely depleted or has some significant individual module problems.

 

Put a 3/4inch (same as 19mm) boxed end wrench on the engine crankshaft pulley bolt and try to turn over the engine manually. If it wont turn over it could be that the transmission fluid has never been changed and the planetary gear inside his transmission is locked up. We got a car with 170,000 miles and this is what happened to it. Because the HV battery could not turn over the engine it gave and error code that said the HV relay was bad. This was not true since that HV battery was working in one of my other six Priuses. We took off the transmission pan and there was so much crud (technical term for fine graphite looking metal shavings) they covered the pick up tub screen. We checked the pick up tubes o-ring and it was fine. We separated the engine and transmission to verify the engine would manually turn before going to the junk yard and getting a transmission. Installed junkyard transmission and the '01 prius is getting 50 mpg.