Step 55 No RPM and o2 Unresponsive

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gt eunuch
MegaSquirt Newbie
Posts: 9
Joined: Fri Jan 28, 2011 9:25 pm

Step 55 No RPM and o2 Unresponsive

Post by gt eunuch »

Building my MSII unit and I am having a bit of an issue at Step 55.

Specs:
MSII v3.0
Code Version: 2.891
JimStim 1.5

Three ( CLT, MAT, TPS ) are responding on the Real-Time Display, however the o2 sensor, and the RPM signals are not responding as I think they should.

The o2 gauge reads a value from the pot on the JimStim, but only as soon as I turn the JimStim on. If I rotate the pot, the value does not change until I cycle the JimStim power (off then back on).

The RPM gauge does not move at all (stays on 0). I have followed the instructions to use the VR pots (on the MS board) to get a working signal, but nothing ever gave me a RPM on the gauge. I tested the JimStim multiple times, making sure that it is producing a RPM signal (as instructed in the build specs on the JimStim) and this checks out okay.

I followed the build specs to use the VR sensor circuit, and below you will see pictures of these modifications ( jumpering VRIN to TACHSELECT and TSEL to VROUT ).

Overview of the current build
Image

Image

VRIN to TACH SELECT
Image

TSEL to VROUT
Image

Settings/Jumpers on the JimStim
Image

Any help would be greatly appreciated! I have a feeling I must be missing a jumper somewhere on the JimStim, or am missing a setting on Megatune, that is what I am hoping anyway :shock:
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gt eunuch
MegaSquirt Newbie
Posts: 9
Joined: Fri Jan 28, 2011 9:25 pm

Re: Step 55 No RPM and o2 Unresponsive

Post by gt eunuch »

And.................

After reading over the manual again, I realized a few issues.

A. I missed the JS10 to IGN jumper in earlier steps
B. I jumped the wrong jumpers... I had TACHSELECT/VRIN jumped (instead of TACHSELECT/OPTOIN) and TSEL/VROUT jumped (instead of TSEL/OPTOUT)

Sometimes taking a break and coming back to the issue, and calmly re-reading through instructions can help tremendously! Now I am entirely embarrassed :oops:
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