One problem related to owners/service manual has been reported for the 2006 Toyota Prius. The most recently reported issues are listed below.
Gear pops back to neutral from driving or reversing as I started my Toyota Prius 2006 car from my driveway, I put it in reverse and it came halfway to the road and then stopped. I noticed that the gear shift lever had, on its own, shifted back to neutral. I then put the car in drive and tried to accelerate back into the driveway of my home. The car's gear shift lever again moved to neutral. The only way I could move the car back to the driveway was by holding the lever in the drive position manually. I tried the car on my street's small block, but found that the gear kept shifting back to neutral, everytime I let go of the drive or reverse position. In other words, I had to keep the gear in d position manually with one hand to drive around. I feel this is a dangerous situation where the attention is diverted from the road to the gear shift lever every few seconds to see if the gear is in the drive position. I called Toyota today and informed them of this situation.