My engine light came on suddenly one morning. It has been on several days now. We had a diagnostic run on it and there was no code given...only the message Malfunction Indicator Light ON. What could this be? I refuse to go to a dealership to spend $500 for them to tell me that I shook loose a cap somewhere.

 

What year of Camry and engine model?

The code reader used may not have been unable to read the code(s), try another brand/model of code reader.

The cars computer could be bad.

If you have not already done so, reset the computer then determine if the check light comes back on. Depending on year of car this may or may not require a code reader to do so. Sometimes resetting the computer results in a glitch problem fixing itself and the check light staying off.