Inverter & Electric Water Pump Failure
The 12-volt battery replacement was not the final chapter in our recent repair saga.
Several days later, more errors (including the "Hybrid System Malfunction" icon) appeared on the MFD screen. Since these indicated a hybrid system failure, we took our 2002 Prius to the dealer for troubleshooting. With over 70,000 miles on the odometer, we were actually hoping for a hybrid system-related problem, as the regular warranty had expired.
It turns out that the inverter water pump had failed, and the inverter was overheating:
P/N G9020-47021, pump assembly, water w/m = $133.75
Labor to remove & replace = $149.00
Shop supplies & sales tax
Approximate total = $300
The error codes included "P3130", which appeared "due to the inverter running hot"; and the inverter was replaced, per TSB/EG022-04:
P/N G9200-48071, inverter assembly w/con = no charge ($3,500.00 list)
P/N 00272-SLLC2, super long life coolant = no charge
Labor to remove & replace = no charge
Our Prius is back to normal. I feel lucky that this failure occurred now, before the hybrid warranty ran out; and that our total repair cost was only about $425, which includes the 12-volt battery we replaced a few days earlier. Actually, five years on a 12-volt battery is considered "long life" in Arizona. They usually only last about two or three years in other cars, due to the heat.
I got the old water pump back, so I will know what to look for when it fails again. Hopefully, next time I can replace it myself BEFORE the inverter fails (after the hybrid warrantly runs out). I haven't looked to see where it goes, but it looks simple to replace. However, it is probably buried somewhere deep inside or under other parts that will have to be removed.