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Working on a 2008 Jeep Patriot 2.4l with code P2017- intake manifold runner position sensor circuit high. The position sensor gets a PWM feed from the PCM (power side PWM switched) I can energize the position sensor with my scan tool. But what I would like to know is- can I use a 12v jumper wire to the PWM wire back probed at the position sensor to see if it would energize the manifold flaps. Would this fry the PWM transistor in the PCM? Only asking in case my scanner didn't have bi-directional controls for that sensor.
Yes as long as your polarity is correct. Using a test light is the safest way but high current solenoids would need a jumper wire. Putting 12v in a 12v supplies wire does not hurt anything because of equal potential. Don't direct ground the 12v from the pcm before the solenoid. That will fry the driver.
Make sure you have identified power side or ground side correctly.
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Just wondering because the pulse width module is switching between 12v and ground (actually between 3v and ground) when the intake manifold flow valve is in the off position-KOEO---Looked on the internet for a week to find how to energize a PWM circuit without harming the PCM--nothing--so thank you
You may got something mixed up as you're talking about activating a sensor? Possibly you want to test the solenoid that is in charge of the flaps' position.....In this case a signal generator, as mentioned, will allow you to test the actuator accurately. A good signal generator will allow to manipulate waveforms in different ways (sine wave, square wave, step up/down, sawtooth, amplitude, frequency, pulse width, duty cycle, off set being some of the important adjustments).You easily can build a basic pwm generator yourself if you're electronically inclined/interested.
If you're sure about the related voltages and connections you could bridge the wires from another actuator which you can activate with your scanner, eg. vvt solenoid, to the component you want to test, activate it and observe in scan data or a voltmeter for a position change. Do disconnect the substitute actuator and only work one actuator at a time.
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Just to clarify. It is not the the position sensor that is provided a PWM signal and it is not the position sensor that you are jumping. It would be the solenoid or electric motor portion of the manifold tuning valve that you are energizing via the scan tool or jumper wire.
As for the output itself, it is not the driver you need to worry about as long as you're using the correct polarity, it would be the output itself. The PWM is being used to control current flow and when you use a jumper wire, you're applying full current. So just do the test briefly, is the rule I follow. Don't jump it for any extended period of time, just in case you overheat that output. Make sense?
