Page 1 of 1
No crank speed at all
Posted: Sat Sep 16, 2017 8:02 am
by Datbeardo944
Hello everybody, thank you for taking the time to help me with my megasquirt build. I am using MS2 V3.0 with a MegaStim V2.21. The tuning software is Tuner Studio MS V3.0.28. I am looking for a hall effect signal through the VR input. Pots R56 and R52 are both set 6 turns clockwise from full counterclock wise D1 and D2 are both jumpered. There is continuity all the way from pin 14 of the daughterboard to tachselect. No matter what I do with he RPM Pot I get .153 volts on pin 14. I looked at the schematic and went through every part, they all seem ok. What am I missing? Thank you again for the help.
Re: No crank speed at all
Posted: Sat Sep 16, 2017 9:00 am
by trakkies
I'm a bit confused here. D1&2 are part of the opto input. Pots R52 & 56 part of the VR input. Which one are you using?
Re: No crank speed at all
Posted: Sat Sep 16, 2017 2:42 pm
by kjones6039
Quick question..... Are we talking testing on the stim or car?
Ken
Re: No crank speed at all
Posted: Sat Sep 16, 2017 10:42 pm
by Datbeardo944
We are using the VR, or at least that is what i am trying to do.I just thought I would add anything that is "different". We are testing on the stim. however I have tried on the car before too but not since I made a few changes.
Re: No crank speed at all
Posted: Sun Sep 17, 2017 1:00 am
by trakkies
Note that the signal you get from a Stim may not be identical to that from a sensor so you may need to adjust those pots between them.
Generally, I've never needed to adjust R52 so leave that fully CCW. Its purpose is to help with interference, and there won't be any from a Stim.
Start with R56 fully CCW.
Re: No crank speed at all
Posted: Sun Sep 17, 2017 9:18 am
by Datbeardo944
OK, Pots are fully CCW, still no signal
Thank you for all the help!
Re: No crank speed at all
Posted: Sun Sep 17, 2017 9:46 am
by kjones6039
trakkies wrote: ↑Sun Sep 17, 2017 1:00 am
Note that the signal you get from a Stim may not be identical to that from a sensor so you may need to adjust those pots between them.
Generally, I've never needed to adjust R52 so leave that fully CCW. Its purpose is to help with interference, and there won't be any from a Stim.
Start with R56 fully CCW.
Precisely my point in asking the question.......... like Dave, I have never found the need to adjust either pot beyond fully ccw.
Ken
Re: No crank speed at all
Posted: Sun Sep 17, 2017 11:19 am
by Datbeardo944
both pots are full CCW and no matter what I do to the RPM pot on the stim, pin 14 only reads 0.15 volts
Re: No crank speed at all
Posted: Mon Sep 18, 2017 12:24 am
by trakkies
Have you tried the PNP/NPN setting on your Stim?
Does your DVM give an AC voltage reading between tach select and ground with the stim connected and everything powered up and the RPM pots on the stim set above zero?
Re: No crank speed at all
Posted: Mon Sep 18, 2017 3:55 pm
by Datbeardo944
I have tried the PNP NPN (the little switch). I am sorry, but I don't know what a DVM is.
Re: No crank speed at all
Posted: Mon Sep 18, 2017 5:12 pm
by kholman
DVM=Digital Volt Meter