I got stuck on ice this morning pointing down a driveway in my '02 Prius with 107,000 miles. Have never had any problem with car before. I was trying to back out and the wheels spun for a while. I pulled forward and then back a few times with no luck. Then the turtle came on, but only when I had the car in reverse. Once this happened reverse was gone, no tire rotation what-so-ever in reverse. Of course I paniced - was the car dead? I pulled down the driveway and managed to turn the car around by pulling foward and then getting out and pushing it by hand to back it around. Drove home a few miles. When I got in my driveway I put it in reverse, no more turtle and it worked fine in reverse. So, what happened and what do I need to fix or do to prevent this from happening again?
The turtle warning light came on to tell you that the traction battery either has low SOC or is overheated. It is likely that the former was applicable to your situation. The reverse gear depends upon the availability of battery power. You don't need to fix anything at this time. However you may wish to note this early warning that your traction battery's capacity is declining.
Thanks. The battery always stays at either half or 75% charge. I had been spinning the wheels for a while, so perhaps I overheated it.
A battery can't charge or discharge as fast at cold temperatures, and the vehicle's control system has to take that into account. Normally, you would have backed up, then taken off, with the engine providing a larger share of power than normal until the battery warmed up. Today, however, was unusual. I'll guess that the battery was pretty cold when you started up. When you spun the tires repeatedly, the load on the battery increased its internal temperature faster than normal, and hit a rate-of-temperature-increase threshold above which the system was unwilling to go. So it dropped the maximum charge discharge rate down to almost nothing—too low to drive MG2—until battery temperature increased. In other words, the system was protecting the battery pack, as it should.
Thank makes sense, thanks for the feedback. I sure did panic at the time when I had no reverse and was stuck in a driveway.