03 Prius Hybrid System Warning Light On

Yesterday, just as I got home my 2003 Prius’ hybrid system warning light came on. This has happened a few times in 15 years but has always been associated with moisture getting into the rear battery vent. In the past, if I turned the car off and on a couple times or waited for it to dry out 15-20 minutes, the light went off and the car drove normally. This time, the weather was hot (95 F.) and dry. I tried turning it on and off several times but the light stayed on. Has anybody out there had a similar experience, or suggestions? Thanks in advance!

You might post this on a Prius site, like priuschat. May be time to have it scanned for codes by a shop familiar with the Prius.

Thanks for the advice. After eliminating simple causes, like fuses or a sticky throttle body, I took it to my friends at Japanese Car Service, and they retrieved the error code for inverter pump failure. The good news is, this was not a very expensive repair. And I now know that this repair shop is absolutely competent to work on hybrids, including battery replacement later on, if I need it. A win/win situation!

Good news! Thanks for letting us know.

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