My master warning light is on, I have a Toyota Prius 2005...

Thanks for using JustAnswer.com! My name is \*\*\*\*\* \*\*\*\*\* I'll try to answer your car questions. I'll start off with some basic checks to do, then we can get into more advanced diagnostics if needed. Let me know if any questions come up, or if there is anything I can do to help! You can update this message at anytime. - I'm sorry to hear about any troubles with the vehicle, but would be glad to try and help! - The triangle warning light means issue with the hybrid system, or with some engine issues like low coolant level or low oil level. Recommend double checking oil level and then the engine for external oil leaks. If not seeing any external leaks, will need to check internal condition of the engine to see if it is burning the oil and will need to be rebuilt or replaced. - If youre seeing any trouble codes setting in any of the modules, please list them to the message and I'll look up diag/repair information. Lemme know if any questions come up while checking things out!

I seem to be driving ok more ingnition lights are coming on if I use the aircon

Would stop off and have it scanned for codes and battery voltage double checked, but the low oil level will cause light to come on. Would make sure no obvious oil leaks and keep oil level topped up. If light stays on, let's see what codes are setting. Lemme know if there's anything I can do to help!

Ok thanks

You bet, glad to help! Lemme know how it goes, or if any questions come up! Thanks again for using JustAnswer.com!