continuity test on the Jimstim

Building and using the Stimulator to test your Megasquirt

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MG David
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continuity test on the Jimstim

Post by MG David »

I have been assembling a Jimstim kit that I bought recently from Diyautotune.

To check that it is going well I have tried to do some basic continuity tests. I have been surprised by some of the results.

1) I tested between the positive on the jack power input and the positive on the terminal block power input. They are connected to each other as I would expect. When I test the negatives they are not connected. Should they be? If so what might be wrong?

2) There does not seem to be a connection between the 2 positive inputs and the 3 position switch. Should they be? If so what might be wrong? Should the power come to the centre pin?

3) When I switch the switch to the on position marked on the board there does not seem to be continuity between any of the 3 pins on its underside. Should there be?

I have checked my multi meter is working.

Thanks,
David
racingmini_mtl
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Re: continuity test on the Jimstim

Post by racingmini_mtl »

Have you checked the schematics linked to on the web page (http://www.jbperf.com/JimStim/jimstim_v1_5_schem.png) ? Also, is that a V.15 board?

There is a diode between the power input and the power switch. So if you measure with the wrong polarity, there won't be any connection. Your other 2 tests don't seem to make sense if you have a V1.5 board.

Jean
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MG David
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Re: continuity test on the Jimstim

Post by MG David »

It is a 1.5 board.

I have the schematic although I was finding it difficult to read last night. Since then I have printed it on a better printer. On the schematic I can see X4 the terminal block power input. I assume that he bit above X4 on the diagram labeled P$1,P$2,P$3 is X5 the jack power input. On that basis i would expect continuity between their grounds. So I will check it again tonight.
MG David
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Re: continuity test on the Jimstim

Post by MG David »

Working my way through the board using the schematic and a muti-meter I found a number of poor solder joints. I have also identified a couple of LEDs the wrong way round. Must read the instructions more carefully in future.

I got the Jimstim kit because I had issues with the MS1 v2.2 I built not providing the correct ignition timing. So I think I need to do a similar exercise on that with the schematic and multi-meter.
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