So the parameter identification data (PID) you are looking for, is a pulse width modulation (PWM) from the PCM to the fan controller. Reading the engine coolant temperature may show a 25% PWM as the engine get warmer, then 50%, 75% and 100%. Unless the A/C system is turned on, if they are not using a trinary switch, then a simple pressure switch on the high side, most likely at the dryer, but the fan(s) turn on at a set pressure for R143a. I had a Mazda MPV giving to me by a family member, but Fords/Mazda shared power train is going on decades before the second generation Ranger. I am not familiar with control systems and was hoping the PCM provided a ground for on-off. I guess not. I think the scope had some electoral noise even if the engine was off. But to get a signal, the key has to be on. I would just make sure everything is turned off and if possible, go straight to the battery and make sure the connections are clean. Interesting, but using PWM would reduce the amperage requirements, alternator load and increase fuel economy. In today’s requirements, I am sure this is why PWM is used. I will be watching for #2 video and get the conclusion. It is a shame to save a little fuel, it takes a $200 fan module. Damn EPA!
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Great video,can you please tell me where did you find the wiring diagram?
So the parameter identification data (PID) you are looking for, is a pulse width modulation (PWM) from the PCM to the fan controller. Reading the engine coolant temperature may show a 25% PWM as the engine get warmer, then 50%, 75% and 100%. Unless the A/C system is turned on, if they are not using a trinary switch, then a simple pressure switch on the high side, most likely at the dryer, but the fan(s) turn on at a set pressure for R143a. I had a Mazda MPV giving to me by a family member, but Fords/Mazda shared power train is going on decades before the second generation Ranger. I am not familiar with control systems and was hoping the PCM provided a ground for on-off. I guess not.
I think the scope had some electoral noise even if the engine was off. But to get a signal, the key has to be on. I would just make sure everything is turned off and if possible, go straight to the battery and make sure the connections are clean. Interesting, but using PWM would reduce the amperage requirements, alternator load and increase fuel economy. In today’s requirements, I am sure this is why PWM is used. I will be watching for #2 video and get the conclusion.
It is a shame to save a little fuel, it takes a $200 fan module. Damn EPA!
2010 mazda6 where is the cooling fan module located