testing optispark off the car
#1
testing optispark off the car
This afternoon was looking at my assortment of optisparks that came off running motors. Either I toss them or use them.
I would like to use the rear optical portion of the unit if I was sure it was ok.
Is there any way to test the optical pickup off the car.
John
I would like to use the rear optical portion of the unit if I was sure it was ok.
Is there any way to test the optical pickup off the car.
John
#6
Re: testing optispark off the car
Pink/black is ground. Red is +12. Purple/White is high res. and the Red/Black is low res. Both will vary from 0 to 5 volts when rotated. One will change faster than the other so rotate slowly or your meter will not keep up.
#7
Re: testing optispark off the car
I know this is an old thread but I'm hoping to get clarification on what is discussed above. I have two opti's I've been bench testing per the above procedures and I think I might be missing something. Between ground and terminals A and B I'm getting well under a volt, but the numbers are going up and down as I spin it. One opti goes between .005 and about .3 volts (on DC setting) on both high and low res. While the other opti goes between about .010 and .8 volts on both terminals.
are they both toast? Shouldn't the voltage go up and down between 1-5 volts on both, just at different speeds?
Thanks!
are they both toast? Shouldn't the voltage go up and down between 1-5 volts on both, just at different speeds?
Thanks!
#8
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Join Date: Jul 2010
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Re: testing optispark off the car
12 power goes to pin C, ground goes to pin D.
Normally there are resistors inside the pcm, one going from for pin A to 5vdc and another going from pin B to 5vdc.
For simple testing purposes, you can connect the resistors to 12v instead of 5v. Resistor values inside the pcm are about 3900 Ohms but you can use anything from 1000 Ohms to 10,000 Ohms and get good results. Measure with a scope at pin A and/or B. Without the resistors, you will get about zero volts at both.
Normally there are resistors inside the pcm, one going from for pin A to 5vdc and another going from pin B to 5vdc.
For simple testing purposes, you can connect the resistors to 12v instead of 5v. Resistor values inside the pcm are about 3900 Ohms but you can use anything from 1000 Ohms to 10,000 Ohms and get good results. Measure with a scope at pin A and/or B. Without the resistors, you will get about zero volts at both.
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