CPS bypass/mimic
#1
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Year: '97
Model: Cherokee
Engine: 4.0 L High Output
CPS bypass/mimic
The crankshaft position sensor in my 97 Jeep Cherokee has packed up.
The sensor has a 5v supply, it then sends a smaller voltage to the PCM (0.5v - 5v) according to the position of the magnet in the sensor.
Obviously the sensor has set output values depending on the engines Revs.
Therefore, my question to everyone is whether it would be possible to design a circuit that 'mimics' the Crankshaft position sensor output?
By tapping into the tachometer signal for the engine RPM and synchronising set RPM values to set voltage outputs would one be able to fool the PCM into thinking that there is a CPS and that its working?
Thanks for your help!
The sensor has a 5v supply, it then sends a smaller voltage to the PCM (0.5v - 5v) according to the position of the magnet in the sensor.
Obviously the sensor has set output values depending on the engines Revs.
Therefore, my question to everyone is whether it would be possible to design a circuit that 'mimics' the Crankshaft position sensor output?
By tapping into the tachometer signal for the engine RPM and synchronising set RPM values to set voltage outputs would one be able to fool the PCM into thinking that there is a CPS and that its working?
Thanks for your help!
#2
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Year: 89
Model: Cherokee
Engine: 4.0
The crankshaft position sensor in my 97 Jeep Cherokee has packed up.
The sensor has a 5v supply, it then sends a smaller voltage to the PCM (0.5v - 5v) according to the position of the magnet in the sensor.
Obviously the sensor has set output values depending on the engines Revs.
Therefore, my question to everyone is whether it would be possible to design a circuit that 'mimics' the Crankshaft position sensor output?
By tapping into the tachometer signal for the engine RPM and synchronising set RPM values to set voltage outputs would one be able to fool the PCM into thinking that there is a CPS and that its working?
Thanks for your help!
The sensor has a 5v supply, it then sends a smaller voltage to the PCM (0.5v - 5v) according to the position of the magnet in the sensor.
Obviously the sensor has set output values depending on the engines Revs.
Therefore, my question to everyone is whether it would be possible to design a circuit that 'mimics' the Crankshaft position sensor output?
By tapping into the tachometer signal for the engine RPM and synchronising set RPM values to set voltage outputs would one be able to fool the PCM into thinking that there is a CPS and that its working?
Thanks for your help!
#3
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Year: '97
Model: Cherokee
Engine: 4.0 L High Output
So you're saying that the tachometer gets its data from the CPS, not from another source?
Is that a fact or are you assuming? Im just double checking so Im sure!
No offense meant!
Thanks for your timely response!
Is that a fact or are you assuming? Im just double checking so Im sure!
No offense meant!
Thanks for your timely response!
#4
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My understanding of it is all other parts of the way a 4.0L get there signal from the CPS.
So there is no way to by-pass or "fake" a CPS signal.
So there is no way to by-pass or "fake" a CPS signal.
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Ok. Thanks for all the help!
So I have no choice but to buy a new one then! Pity - thought I could save a few bucks!
Anyway... Thanks again!
This forum rocks! Response time is excellent!
So I have no choice but to buy a new one then! Pity - thought I could save a few bucks!
Anyway... Thanks again!
This forum rocks! Response time is excellent!
#7
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Year: 89
Model: Cherokee
Engine: 4.0
No offense taken,it is a fact though that all cars get there signal for the tach from the coil,pcm,or cps. if your car has a crank shaft positoner it is used to send signals to the first two,so weather the signal comes directly from the cps or not,it is what starts everything in motion. Before cars had a cps the tach got its signal from the coil,and flex plates did not have tone rings.
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#9
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Year: 1988 limited
Model: Cherokee
Engine: 4.0 litre
The crankshaft position sensor in my 97 Jeep Cherokee has packed up.
The sensor has a 5v supply, it then sends a smaller voltage to the PCM (0.5v - 5v) according to the position of the magnet in the sensor.
Obviously the sensor has set output values depending on the engines Revs.
Therefore, my question to everyone is whether it would be possible to design a circuit that 'mimics' the Crankshaft position sensor output?
By tapping into the tachometer signal for the engine RPM and synchronising set RPM values to set voltage outputs would one be able to fool the PCM into thinking that there is a CPS and that its working?
Thanks for your help!
The sensor has a 5v supply, it then sends a smaller voltage to the PCM (0.5v - 5v) according to the position of the magnet in the sensor.
Obviously the sensor has set output values depending on the engines Revs.
Therefore, my question to everyone is whether it would be possible to design a circuit that 'mimics' the Crankshaft position sensor output?
By tapping into the tachometer signal for the engine RPM and synchronising set RPM values to set voltage outputs would one be able to fool the PCM into thinking that there is a CPS and that its working?
Thanks for your help!
The cps has therefore a double function, and it's functionality is linked to the dynamics of the engine.
If you had a double channel Fluke wave generator with frequency sweep and a Tektronix 640 oscilloscope to sinchronize it with some sort of RPM input, it could be possible to emulate the cps signal in theory, but absolutely not worth doing it.
There are many other awesome things you could do with this kind of transducers, i'll give you a hint: ABS.. lockers...ABS..lockers!!!
#13
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Year: 1990XJ/1989MJ
Model: Comanche
Engine: 4.0L Renix
There were some CPS sensors that were mounted to the front of the engine at or replacing the harmonic balancer. That company went out of business though. There may still be some around. Hesco sold them at one time.
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Year: 1988 limited
Model: Cherokee
Engine: 4.0 litre
It worked fine, and i made also an adjustment of the sensor making oval holes on it to slide it up and down around the bolts and change the timing, actually a cheap mod we could all do on our CPS on the Jeeps too.
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