I’m currently working on a 2011 Mazda cx-7 2.5L non turbo California emissions and it has a p2006 code which has to do with the intake manifold runners being stuck closed.
I pulled up a trouble tree on identifix and followed it and it led me to replacing the solenoid. I used the following chart listed to conclude this!
however I felt the trouble tree wasn’t covering all of the bases so I decided to take it a few steps further and I tested all the wiring circuits for the variable tumble solenoid (IMRC) and the variable tumble switch to the ECM. All circuits passed voltage drop tests and had next to 0 resistance so I move forward.
I tested the solenoid function with a power probe and it worked fine, vacuum is good from solenoid to manifold and the arm for the intake runner is not broken.
What I did notice is that the ground side terminal B of the IMRC solenoid has 3.5v with key on engine off and with engine running and the plug unplugged I was getting 3.5v as well. I also backprobed the terminal while the car was running before and after conditions were met and I got 12v before and 0v after which I assume the system is grounding correctly then, but my scan tool reads opposite of the chart which is confusing me.
My scan tool does not support any bidirectional testing without paying for a subscription for Mazda which is what I’m trying to avoid doing. So my question is, does the ECM for this car put out 3.5v to the ground circuit before it meets the requirements for the internal switch to flip? Because if so then I have a bad solenoid but if not I think I have a bad PCM.
I pulled up a trouble tree on identifix and followed it and it led me to replacing the solenoid. I used the following chart listed to conclude this!
however I felt the trouble tree wasn’t covering all of the bases so I decided to take it a few steps further and I tested all the wiring circuits for the variable tumble solenoid (IMRC) and the variable tumble switch to the ECM. All circuits passed voltage drop tests and had next to 0 resistance so I move forward.
I tested the solenoid function with a power probe and it worked fine, vacuum is good from solenoid to manifold and the arm for the intake runner is not broken.
What I did notice is that the ground side terminal B of the IMRC solenoid has 3.5v with key on engine off and with engine running and the plug unplugged I was getting 3.5v as well. I also backprobed the terminal while the car was running before and after conditions were met and I got 12v before and 0v after which I assume the system is grounding correctly then, but my scan tool reads opposite of the chart which is confusing me.
My scan tool does not support any bidirectional testing without paying for a subscription for Mazda which is what I’m trying to avoid doing. So my question is, does the ECM for this car put out 3.5v to the ground circuit before it meets the requirements for the internal switch to flip? Because if so then I have a bad solenoid but if not I think I have a bad PCM.
