understanding crank sensor signals
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understanding crank sensor signals Concerning a crank signal from an LS1 (24x reluctor wheel) we observe a typical hall effect square wave output. There is a hires and lores period. Which is what?
The reluctor uses 2 different width notches (12* and 3*) that are 15* apart.
So for example...
|'|_|'|,||_||_||_|'|,|'|,|'|... etc
The reluctor uses 2 different width notches (12* and 3*) that are 15* apart.
So for example...
|'|_|'|,||_||_||_|'|,|'|,|'|... etc
Go here and see the diagram I posted. It details the trigger pattern degree by degree for both the cam and crank sensor. Applicable to the 2005 and earlier LS series engines.
http://www.msextra.com/viewtopic.php?p=155569#155569
If triggered off the trailing edge, you will end up with equidistant 15 degree events, 24 x per revolution.
http://www.msextra.com/viewtopic.php?p=155569#155569
If triggered off the trailing edge, you will end up with equidistant 15 degree events, 24 x per revolution.
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From: So.Cal.
Originally Posted by 96 Comp T/A
Go here and see the diagram I posted. It details the trigger pattern degree by degree for both the cam and crank sensor. Applicable to the 2005 and earlier LS series engines.
http://www.msextra.com/viewtopic.php?p=155569#155569
If triggered off the trailing edge, you will end up with equidistant 15 degree events, 24 x per revolution.
http://www.msextra.com/viewtopic.php?p=155569#155569
If triggered off the trailing edge, you will end up with equidistant 15 degree events, 24 x per revolution.
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From: Australia
Thanks "99 Comp T/A".
But it still deosnt tell me what is referred to as the hires and lores signal? Or am I missing something?
Is the lores signal the pulses which occur while the cam signnal is low (0v)?
But it still deosnt tell me what is referred to as the hires and lores signal? Or am I missing something?
Is the lores signal the pulses which occur while the cam signnal is low (0v)?
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There are actually 3 patterns on that wheel with a unique 1/2 rotation identifier for determing cylinder pair is up within 1/2 rotation.
there is a 4x rising edge 8x trialing edge 24x trialing edge. The reason for the dual wheels opposing is to make sure there is no misignalling in the sensor from noise.
The sensor is a dual pole Hall Switch. Each pole sits on a sensor track.One when is high the other is pulled low.
this flips a transistor to either on or off. when the sensor is high the transistor is off and voltage goes to 5v when it on it pulls it to ground the transistor is on and the signal is pulled low.
for the life of me i cannot remeber which is which at the moment. If I am correct on this though it should be the wheel clossest to the front of the engine that is the actual wheel it reads from.
the camshaft position sensor should go High when cylinder 1&6 are up but only #1 is on TDC power stroke. The sensor should go low when #6 is on its TDC power stroke and #1 is on the exhuast stroke.
there is also a TDC marker in the crank wheel for pairs 1&6 at TDC for both cylinders. the cam orientation detrimines which is 1 tdc and which is not.
there is a 4x rising edge 8x trialing edge 24x trialing edge. The reason for the dual wheels opposing is to make sure there is no misignalling in the sensor from noise.
The sensor is a dual pole Hall Switch. Each pole sits on a sensor track.One when is high the other is pulled low.
this flips a transistor to either on or off. when the sensor is high the transistor is off and voltage goes to 5v when it on it pulls it to ground the transistor is on and the signal is pulled low.
for the life of me i cannot remeber which is which at the moment. If I am correct on this though it should be the wheel clossest to the front of the engine that is the actual wheel it reads from.
the camshaft position sensor should go High when cylinder 1&6 are up but only #1 is on TDC power stroke. The sensor should go low when #6 is on its TDC power stroke and #1 is on the exhuast stroke.
there is also a TDC marker in the crank wheel for pairs 1&6 at TDC for both cylinders. the cam orientation detrimines which is 1 tdc and which is not.
Last edited by LS1curious; Jul 10, 2007 at 11:25 AM.
