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Old 09-27-2008, 08:02 PM
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subford
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I have read but not tested that is should be:
The PCM needed to see a PIP square wave with a peak
amplitude of 6.5 volts or more, while the ICM
only needed 5.75 volts to recognize the signal.

I do not know if this is cranking or running.

I use a PIP tester for this.

But I did some playing one time and wrote the following text if that helps.

I have been asked many times how to test a PIP Sensor by itself so here is what I came up with.

The PIP Sensor just has an off and on output but to test it you have to put voltage on the PIP at the plug through a voltage-dropping resistor.

I hooked it up like the diagram below and turned the distributor slowly by hand.
The meter went to full voltage and dropped back to zero as I turned the distributor.
A test light will not work here as it draws to much current.

I did not have a TFI (ICM) module hooked to it during the tests as I wanted to come up with a test to find out if it was the PIP or the TFI that was bad.

This would work to test the PIP Sensor if you had no spark. But if it quit while the engine is warm then you could put a hair dryer on the PIP and crank the engine to test it.

You can also use the 12 Volt Battery in the truck for this test but I was thinking about making a tester at the time with a 9V battery and a LED at the time I did the test.

Information from the web says the voltage dropping resister is 1200 Ohms but when I measure it I get 1.135K Ohms for the resister in the TFI module so I used a 1K.

Then I put a TFI Module on and checked voltage at the PIP Power PIN and it was 11.55 Volts with 12.0 Volts on the Run Power Pin of the Module.
PIP signal out is 0.0 - 11.43 Volts with the 12.0 VDC on the Run Power Pin of the TFI Module.




For more information on the PIP is contained in these two PDF’s.

http://www.wellsmfgcorp.com/pdf/counterp_v8_i2_2004.pdf
http://www.wellsmfgcorp.com/pdf/counterp_v8_i3_2004.pdf
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