MS II w/ JimStim V2 tach signal problems.

[KamikazeGarage]

I'm on step 55, all inputs are working as they should except for RPM. im getting signal at the Stim, I verified this by jumpering one of the bottom plugs for Primary Tach to an led and adjusted the pots.

So far I have jumpered:
IGBTIN to JS10
TACHSELECT to OPTOIN
OPTOOUT to TSEL
IGBTOUT to IGN
and
XG2 to XG1

One other question, What exactly is a pullup? Just a wire soldered to a resistor?

Sorry if its kind of vague, im learning everything about this as i go along.

[slow_hemi6]

Pull Up is an appropriately sized resistor that is connected between a + voltage and another point in a circuit that you want to pull up to that + voltage value. You can also get a Pull Down that is the same idea but pulls the connected point down to ground. If you have a switch that only switches to ground but you want to be able to get either a +v or ground signal from it then a pull up is used so that when the switch is open there is a +v courtesy of the pull up but when the switch is closed you then get a ground. The resistor being appropriately sized means you don't get a dead short when the switch connects to ground because current flow is limited.

[KamikazeGarage]

Awesome thanks!!





Anyone have any ideas on what it could be? I went through the instructions again to see if I missed anything and I check for continuity from the tach header on the JimStim to pin 24 of the DB37 and didn't get anything.. But if I flipped the stim upside down and measure continuity from the tach header to the bottom left pin of the DB37 while its facing up I get continuity

[racingmini_mtl]

Did you install the jumpers as per this: http://www.jbperf.com/JimStim/JimStim_v ... .html#tach ?

Jean

[KamikazeGarage]

Im actually unsure of how to connect that. I jumpered one pin from the square wave to the tach signal pin on the 20 pin header. Are you supposed to jumper the two primary tach pins essentially creating what looks like a loop with the jumper wires?

Because I was unsure I connected a pin from primary tach to an LED to verify signal, and it lit up and changed according to the pots. Is this the wrong signal for MS?

[KamikazeGarage]

I've tried everything. I've figured out megasquirt isn't getting signal at all, the pots work and so does the output so I believe I might have missed something on the board. Is there a way to test for RPM signals/voltage at the DB37 of JimStim

[DaveEFI]

Best place to test for a tach signal is at Tach Select for the input to the VR circuit, and Tsel for the output from the VR circuit to the processor. I use a bare wire loop to link Tach Select to VR in etc to make a convenient way of attaching a 'scope probe or whatever.

[KamikazeGarage]

Can someone tell me if this is the correct way to "jumper" the leads for Hall signal/ square wave

also here are my jumpers, some jumpers are specific for my car as per:
http://www.diyautotune.com/tech_article ... _discs.htm
http://www.diyautotune.com/tech_article ... _240sx.htm

[KamikazeGarage]

So i figured out the board is infact getting a signal. My problem could be with Tunerstudio iteself, or a component. ive gone through installation time after time, and im not missing any components. I am worried I might have put a Capacitor in backwards however, but i doubt it.

https://www.youtube.com/watch?v=oaZBmEEgcXc


I cant seem to find any other igntion options in TunerStudio Lite. I can only access Base and Advanced ignition options, Do I require the premium version?
im stumped

[Matt Cramer]

The jumpers look OK, but are you on the latest MS2/Extra firmware (3.3.3)?

[KamikazeGarage]

I just loaded 3.3.3 on it and see more options, messed around with it for 10 minutes and still cannot get a signal to TunerStudio. What are the correct settings for the Hall effect test with all DIP switches off?

[KamikazeGarage]

I just did a voltage test on the Stims CPU, im getting ~1.5v on pins that aren't 1,2,3,13, and 15.
Could this be the cause of not getting a useable RPM signal? I noticed that the LEDs dont really flash when conducting tests, but they do get brighter when adjusting the pots.
I'll check for shorts



EDIT
I saw an unsoldered pin in the CPU socket. pin #4.
I'll report back with results

[KamikazeGarage]

Something interesting has happened, If I hookup a wire from the tach select jumper to the first ign LED I get a tach signal to TunerStudio!

However this means something is still wrong!

[racingmini_mtl]

That means you don't have a pull up on your MS board so you need one on the JimStim. This is described here: http://jbperf.com/JimStim/JimStim_v2_0_ ... .html#tach.

So remove your jumper to the LED and put a jumper for the 12V pull up.

Jean

[KamikazeGarage]

id kiss all of you if i could

im so excited to finally be able to move on!!!!!!!!!!!!!!!!!!!! ^.^