An orange light stating "malfunction indicator lamp" has appeared on the dashboard of my 1999 toyota Yaris. Have bought car from my sister. She said it used to come on and off with her before too and a mechanic had to hook it up to a PC to get rid of it. I just hope its no more than that.

Did she give you the manual? What you need to know is in there. Check with a dealer on how to get one. Also, they can reset the light for you and tell you if something actually needs to be fixed. Toyota's and other makes require that you put the gas cap on tight; it should start to click. If you don't, you get a warning light. Also, some models will turn on a light at every 5000 mile interval to remind you to do maintenance (mainly oil changes). There is a way to hold down the trip odometer while the key is in the accessories position (the car is not running) which turns out the light.

its the "your an idiot for buying a yaris" light

Your engine is broken. You need a new one. Hope this helps!!!

your roof is peeling back, you need to get a new body kit, and there is a little unicorn jumping in your muffler poking holes and shit. your gonna need a whole new car