94-98 12V CPS Voltage

[Tobin]

Been looking online for what the reference voltage is for a 12v crank position sensor. I figured it was 5v but looks like some chrysler stuff is 8v. Trying to build something to run a regular gasser autometer tach with the stock 12v crank position hall effect sensor. I think I need to feed it 5v and then use a pull up resistor between the power wire and the signal wire. Anyone else do this?

Tobin

[jlbayes]

Have not but I can tell you the pcm does feed it a 5v reference.

[BigPapa]

According to my wiring diagrams, '94-'95 uses an 8V supply, PCM pin 7, Orange wire. '96-'98 uses a 5V supply, PCM pin A17, Violet/White wire.

[jlbayes]

Well I'll be. There is both a 5v and 8v reference from the pcm. 8v supplies ESS and VSS.

1994 Dodge Cummins Wiring Maps - Electrical - Mopar1973Mans Dodge Cummins Forum

[Tobin]

Thanks! I wonder if a 5v would work anyways with the 94-95 hall effect sensor. Has anyone made something like that to work with a aftermarket gasser tach? I had one working on my 97 with the PCM sending the crank sensor voltage and a 1K ohm pull up resistor between the signal and +12v wire on the tach. I can't get it to work with a 94-95 hall effect sensor and +12v to the sensor.

[Tobin]

So I built a 5v voltage regulator and fed the +5v to a 96-98 crank position sensor and used a pull up resistor (1k ohm) between the signal wire a +12v power and hooked a 4cyl gas tach (2 notches in a Cummins balancer) to it and it seems to work good. I probably need to verify it with a held held tach or something.

Maybe Jory will chime in and let me know if this is accurate or not.

[WUnderwood]

Gotta ask, what is the 'hall effect'?

[Tobin]

Hall effect sensor is what the crank position sensor is. It detects the notch in the harmonic balancer.

[jlbayes]

Originally Posted by WUnderwood

Gotta ask, what is the 'hall effect'?

A Hall effect sensor is a transducer that varies its output voltage in response to a magnetic field. Hall effect sensors are used for proximity switching, positioning, speed detection, and current sensing applications.

Google definition.

Feed a sensor voltage and pick the pulse from the passing component/widow.

[GAmes]

Originally Posted by Tobin

Hall effect sensor is what the crank position sensor is. It detects the notch in the harmonic balancer.

Ok, just for clarity, it is an engine speed sensor, it cares not what the crankshaft's position is. The damper, (not a balancer), can be installed in any position.

[DieselWrencher]

Originally Posted by Tobin

So I built a 5v voltage regulator and fed the +5v to a 96-98 crank position sensor and used a pull up resistor (1k ohm) between the signal wire a +12v power and hooked a 4cyl gas tach (2 notches in a Cummins balancer) to it and it seems to work good. I probably need to verify it with a held held tach or something.

Maybe Jory will chime in and let me know if this is accurate or not.

This was my plan with my set up on my 72 for my dakota digital cluster, I just haven't gotten that far yet. I was just going to use +12v but maybe I'll have to reduce it too?

[dieselpolaris]

If you want to use an aftermarket tach of any sort the easiest way to do it is to take a magnetic pickup and connect it with an hei ignition module out of a gm distributer. Will allow you to run any gasser tach out there. We're using this setup on our puller to run a sunpro 8k tach and it worked flawlessly off the 4 balancer bolts.

[Tobin]

Originally Posted by GAmes

Ok, just for clarity, it is an engine speed sensor, it cares not what the crankshaft's position is. The damper, (not a balancer), can be installed in any position.

Well it I believe it is called a crank position sensor but yes it is just a speed sensor. Damper/balancer...same thing. Yes, I know some engines are externally balanced and this isn't.

Originally Posted by dieselpolaris

If you want to use an aftermarket tach of any sort the easiest way to do it is to take a magnetic pickup and connect it with an hei ignition module out of a gm distributer. Will allow you to run any gasser tach out there. We're using this setup on our puller to run a sunpro 8k tach and it worked flawlessly off the 4 balancer bolts.

Good to know, I like that idea too.

[Tobin]

Originally Posted by DieselWrencher

This was my plan with my set up on my 72 for my dakota digital cluster, I just haven't gotten that far yet. I was just going to use +12v but maybe I'll have to reduce it too?

I am not sure if the +12v will work. I am scared to try it and fry a $100 sensor. I tried hooking up +12v to a 94/95 +8v sensor and it didn't work but the sensor could have been bad in the first place. I am not sure the extra voltage would kill it.

[GAmes]

Originally Posted by Tobin

Well it I believe it is called a crank position sensor ...... Damper/balancer...same thing.

Believe what you want. The factory service manual calls it an engine speed sensor and so does Cummins Quickserve. There is also a note on Quickserve that notes the vibration damper. They are not the same as a balancer, regardless of those too lazy to learn the proper nomenclature.

Cummins QuickServe Online | COLA

[Tobin]

Originally Posted by GAmes

Believe what you want. The factory service manual calls it an engine speed sensor and so does Cummins Quickserve. There is also a note on Quickserve that notes the vibration damper. They are not the same as a balancer, regardless of those too lazy to learn the proper nomenclature.

Cummins QuickServe Online | COLA

Ok, thanks for the total derail.

[GAmes]

Originally Posted by Tobin

Ok, thanks for the total derail.

Happy to provide a little instruction. Any derail was your pointless argument.

[Tobin]

Originally Posted by GAmes

Happy to provide a little instruction. Any derail was your pointless argument.

You provided nothing constructive.

[BigPapa]

Come on fellows, give it up.

I think everyone understands what everyone here is talking about except for Mr. Underwood.....

[biggy238]

What is the purpose of the pull up resistor in this circuit? Curious is all.

What is Hall Effect and How Hall Effect Sensors Work - YouTube

Sent from my XT1575 using Tapatalk