No tach output
#3
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Do You have 12V and ground at the cam sensor plug?
Do you have continuity between the signal return wire at the cam sensor and the PCM????
Just fixed a truck a couple of days ago that had no tach and cam sensor codes, found a lack of 12 volts at the cam sensor!!!
Mike
Do you have continuity between the signal return wire at the cam sensor and the PCM????
Just fixed a truck a couple of days ago that had no tach and cam sensor codes, found a lack of 12 volts at the cam sensor!!!
Mike
#4
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I just verified 12vdc at the cam sensor 12v reference, good ground on the low reference and continuity through the signal line to the pcm all checked good. Re-checked 12vdc present at tach, good ground, also continuity from PCM C2 pin 10 to tach, no issues. I am stumped, I think I am going to pull the tach out and bring it into work, put it on my waveform generator and see if I can get it to work.
I noticed the shift light only comes on at 0 with the key in run, engine off. When the key is cycled on it goes to the selected shift point but the light does not come on, so i believe it may be the tach itself. I do not remember if the shift light comes on before every start up.
I noticed the shift light only comes on at 0 with the key in run, engine off. When the key is cycled on it goes to the selected shift point but the light does not come on, so i believe it may be the tach itself. I do not remember if the shift light comes on before every start up.
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#9
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If this is an engine swap or you are using an aftermarket tach and you are using an 03+ pcm you may need to do a pull up resistor. http://www.lt1swap.com/lsx_tach.htm
My tach did not work until I did this circuit, now works like a champ.
My tach did not work until I did this circuit, now works like a champ.
#10
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Bringing this one back. I've got P0342 Low Voltage Cam Position Sensor, and no tach. From what I've already learned in this thread, I'll check the wiring for good voltage, but what about the tach!?!?!