I posted my problem on another forum priuschat.com and someone there referred me to this forum/posting. Rather than repeating my sad story, I'll just cut and paste my two postings from the other forum. I received one advice of disconnecting and connecting 12V battery which someone in that forum used in a similar circumastance.
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My posting on Wed, 4/26, night
Bought a Prius two weeks ago. Three days ago it showed engine check light, so took it to the dealer. Service dept diagnosed it as an engine coolant sensor failure (he said it was a sensor that senses when the temperature is very low and takes some action.) and he has ordered the part which will take one week to receive. He rebooted the computer in the car to get rid of the light and and said that the car is driveable and to ignore the engine check light if it ever came back on again. The failed sensor would not affect any other systems. BTW, it has been hot last few days.
Yesterday, the gas engine just stopped while driving. The brake, engine check and a red triangle came on and display said "problem". Luckily I was near home and the car drove on the battery power but drained pretty fast to empty by the time I got home, around 1/2 mile. I turned the car off and on and the gas engine was dead, and the same warning lights came on.
Called the dealer today, had the car towed in. This morning at home, the gas engine was dead and it still flashed the same warning lights when I backed off and loaded the car on the tow on battery power. However, when I got to the dealer and unloaded the car and turned it on to drive a
few feet, the gas engine was now working with only engine check warning light on. I turned the engine off/on once more and now there were no warning lights at all.
Have left it at the dealer's for tests and the replacement of the sensor when it comes in.
Any similar experience ? Any advice ?
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My update today
Thanks for all the help and tips.
The vin is much newer than the ones mentioned below that needed the ECU update.
The service manager said that they ran dignostics and talked to Toyota. He said that the ECU did show a failure code (indicating that the engine had indeed failed) but don't understand how the ECU got there and are calling it a software glitch. A toyota engineer is promised to fly out here if it happens again. BTW, I didn't ask/get the failure code number or didn't get that toyota is working on this; both of which have been mentioned in a related message.
I have driven for two days so far (~ 100 miles) w/o any warning lights. Keeping my fingers crossed and will try the 12V battery disconnect tip.
thx.
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