problems starting my yaris

[Sir A.Y. Atoyot]

Originally Posted by big lo

Its the battery YT, the dash will light up because it still has a little power, but if you someone to jump start you car to run, then its the battery. You can try this while your car is running take of the positive and disconnect it, if the car shuts off its the alternater, try it and W/B. Now if the car is still running have the battery replaced.

Disconnecting the battery while the car is running is a very bad idea. The battery is the only thing that holds the alternator down somewhere in the vicinity of 12V - disconnect it and it can produce hundreds of volts. You could seriously die. Even if you are lucky and avoid death, there are lots of systems in the Yaris that aren't built for high voltage. You could end up with fried electronics.

Old cars with generators had a current limiter in the voltage regulator, so removing a battery terminal was a common troubleshooting step, oh about half a century ago.