I found this reply on the web. You might to get the codes read.
The triangle warning light is a master warning light. There is a malfunction in the hybrid and engine control units. The most common problem is because the engine did not start when commanded to. This willl set a P3191 and a P3101 codes. Try turning the key off and restarting. If the engine fails to start the hybrid battery will run down to the point you won't get it started.