Jump to content

MS2 3.0 - Troubleshooting Tach/Trigger Signal

Recommended Posts

A while back I had vowed to build and install this ems solely through diligent research on the forums, youtube presentations (sloppy mechanics vid are particularly good btw) and deductive problem solving.  A couple months later and here we are; still troubleshooting and hoping to sponge some insight from the  datsun hive mind.

THE ISSUE:  I am not able to register a tach signal in tuner studio (w/ stim) utilizing the VR conditioner circuit.  I had initially built the board utilizing the HALL circuit and WAS able to register a tach signal, however I changed this over to VR upon reviewing feedback on this forum.


  • I have set (and adjusted) the R56 trimmer resistor (when ‘trimmed’ all the way, it’s registering ~.7V when measuring from top of R54 – I’ve increased this with no luck).
  • There is no signal data when utilizing the trigger / composite logger feature in tuner studio
  • Tach signal from the jimstim has been tested, tach jumper [on the stim] reflects VR circuit. 12V pullup jumpers installed.  I've tried varied dip switche configurations on the stim to no avail.  Currently set to base EDIS/Distributor. 
  • All recommended testing has passed per the msextra buildup instructions EXCEPT THE FOLLOWING:
    • I am reading NO VOLTAGE on +5V terminal in the prototype area and BOOT terminals (should be 5V?)  I suspect this is the result of some hardware issues, but can't seem to nail it down.
  • I‘m running 3.4.2 Firmware
  • 12V pullup w/ 1k 1/4w resistor is installed on PIN 24 (under the hood - not on the board)
  • Board utilizes the BIP373 add on – used to drive [1] ignition coil directly via PIN 36.


Setup on the car is as follows (although I don’t believe it’s relevant to the issue at hand)

  • L28ET swap in a 1973 240z
  • 82 ZXT distributor with DIY autotune 12-1 trigger wheel (has been properly phased per instructions on the forum)
  • 440cc bosch-style Low-Z injectors


Photos of the board, bay and msq files are linked below.

Humbling swallowing my pride as I ask for some feedback.


Thanks in advance! -t




tomzapper240 baseline.msq

Edited by tomr240zap
Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...