MicroSquirt.com read only forum (Jan.15,2018)

Im running MSII V 3.0 PCB.

Im having trouble getting an RPM signal to MS. I have voltage to the coil and module. While cranking I see 3.9 volts from the VR sensor. I have 12V going to the MS from the PIP, but it constantly stays at 12V. If I have read the manual correctly, It should drop to 0 right? I also show no voltage from the SAW wire.

Does anyone have any suggestions? While cranking with the real time display up, the RPM guage jumps to 1 when I first start to crank and the red cranking bar comes up on Megatune. If I stop cranking and go to start it again, I get nothing. I tried switching the VR wires, but then I get nothing at all.

RichyQuest87,

Are you measuring the voltage using an oscilloscope or a digital voltmeter? I ask because a voltmeter is generally way too slow (they are deliberately highly damped so the the numbers aren't flickering all the time). If it measures frequency, that might tell you a bit.

Did you install and jumper for the Hall input circuit in the assembly? Does it work on a stim?

Lance.

Lance,

I was measuring with a digital voltometer. I took the MS out of the case on Sunday and checked that I had all the components and jumpers in there. It do get an RPM signal on Megatune with the stim.

I checked a few more things today. I checked to make sure I had wires running to pins 24 and 36 on the relay cable. I rechecked having spark in limp home mode. I do have spark, but its very weak and orange. I pulled my crank wheel off as I have the missing tooth 9 teeth BEHIND the sensor instead of AHEAD of it.

fixed the crank wheel. It made no change. I still only see 1 RPM on MS everyone once in a while. If I switch VR wires... nothing. Ive checked just about as much as I can think of. Wiring of the EDIS system, all components on the MS itself, I confirmed wires being at the pins of my relay cable, setting in MegaTune. I do have a couple questions:

1. On the EDIS page it says to do the Hall ciruict step 50. I assumed it would be 50a. Is that the right one?
2. On the wiring schematic, it shows the #2 pin of the coil connector going to both 12V and ground. I have it wired to a 12V while cranking wire. Is that what it needs to be?
3. As of right now my VR wires, and PIP and SAW wires are not shielded? would this cause me to not have a RPM signal to MS?

Ok just figured something else out. when i was testing with my stim to see if i had RPM signal I was testing it on 2 different computers. I was not aware that the computer I was testing with the stim on was not set for EDIS. When I changed it to EDIS and all the correct settings I get no RPM signal now when testing with the stim. Any ideas on what that could be?

RichyQuest87,

Yes, do step 50.a - I have fixed this on the page.

Pin #2 on the coils packs go to 12 Volts, with a capacitor to ground.

Do you get an rpm with a stim on the bench? This is the best way to make sure the input circuit is functioning.

What code are you running? I would reload the V2.36 in any case.

Lance.

Lance,

After I changed my settings on the computer I was using with the stim (not the same as the laptop in the car) to the EDIS settings (rebooted MS), I get no RPM signal

Lance,

After I changed my settings on the computer I was using with the stim (not the same as the laptop in the car) to the EDIS settings (rebooted MS), I get no RPM signal. I did get it on the stim before changing to the EDIS options.

Is the capacitor to ground necessary

RichyQuest87,

Okay, that's good to know. The MegaSquirt should have no trouble triggering on the stim, so there's some sort of hardware problem. Look at the tips here: http://www.megamanual.com/ms2/V3trouble.htm, there are hints on what to check when the rpm isn't showing up and how to trace the signal with an 'LED tester'.

Lance.