QuestionJohn,
The ECU gives me two Pxxxx codes: P0715 and P0431.
The P0715 indicates a malfunction of the "Input/Turbine Speed Sensor".
I was able to find that sensor, and measure 276 Ohms across it, with the engine off. A mecahnic told me that the sensor is probably ok and the problem may be loose connection to the ECU.
The second code, P0341, I just found out about it yesterday when I took it for a smog test, here in L.A. The Smog Test computer says: "Warm up Cat efficiency below thershold (Bank2)".
Could I just have a bad ECU unit? Where can I find the ECU? I just want to look at it and see that everything is connected properly.
My Mazda came with a 3 year warranty, which has passed. But I understand that California emission laws extend the warranty on ECUs and Cats..
What do you think I should do? Thanks John.
Yours,
Don J.
Answer1 in 500,000 cases of electrical gremlins lead to a bad ECM and most failures are documented to a certain make and model.
Take it into a qualified mechanic and have it run on the diagnostic scanner. Trouble codes only list events that have happened and do not register events that are happening. With the advent of OBD2 the mechanics of the world were blessed with the ability to sample sensor outputs and running condition while the engine is running.
This could be as simple as a misfire due to a bad plug and possibly a bad sensor. As an ECM will cost between $400-$1000 with no guarantee of fixing the problem the best solution is to let the man with the $10K magic box see what he can find.
The P0415 is in reference to the transmission speed sensor output and is a Hall Effect sensor "uses magnetic pulsations" and is impossible to test without an oscilloscope and a legend of parameters for that sensor.
P0431 is referenced to a bad O2 sensor input and could be as simple as a new O2 sensor and as bad as a catalytic converter failure.
The devil is in the details!
Regards,
John
