I got an 2009 toyota prius I was driving home one day and car shut off and check engine light came on after 10 mins of the car being off I try to turn it on, it started with the check engine light still on main battery light came off, I ran to AutoZone and got my car scan for codes and P0121 was my code tps my car has 120k miles what should I do clean the throttle body? Replace the sensor? How would I test the sensor if it's bad? Thank you
welcome to PriusChat! The fastest and most reliable way you can ever get answers to questions like that is to view the service manual for the exact year of your car on techinfo.toyota.com. Start with volume 1 for the diagnostic info. When you look up your code in the engine diagnostics section there will be a page number next to it, when you go there you'll find a whole procedure for testing. This is a lot more useful information than the fortune-cookie's worth the AutoZone scan tool gives you. Hope this helps! -Chap
The throttle position sensor probably has failed and the throttle body would need to be replaced since the TP sensor is not designated field-replaceable. Or, you have a problem with the wiring harness connecting to that sensor. Consult techinfo.toyota.com for information about how to replace the throttle body.
Hi there. I'm a newb but had something similar happen to me. I got the same code and was able to clean the throttle body and it was very dirty. Have not had the code return since.
