Strange PWM spike

[Peter Florance]

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PROF315 sent me an MS3 setup to test a strange PWM idle problem.

I'm thinking it is not hardware as I see the spikes in the datalog.

It may be a problem in his msq but nothing stands out to me.

I've attached msq and datalog. This was logged with pre1.2alpha but also does it with pre1.4alpha

Thanks!

[jsmcortina]

That's very weird and looks to be every four seconds. Has this been tested with the current pre-1.2alpha7 version? I take it you've repeated the problem on the bench?
I'll aim to look at it in the morning.

James

[Peter Florance]

That's very weird and looks to be every four seconds. Has this been tested with the current pre-1.2alpha7 version? I take it you've repeated the problem on the bench?
I'll aim to look at it in the morning.

James

I have not tried the current, but I will.

[jsmcortina]

How is the AC input wired on the car?

The "Nitrous" pin input normally expects a 12V signal and as such the JP8 jumper should NOT be fitted on the MS3X.
In this MSQ the normal "nitrous pull-down" setting is disabled.

When I was testing this allowed the nitrous input to float around and trigger the AC on/off all the time. The user settings cause the four second interval.

When I enabled the pulldown in software the feature behaved as expected.

NFF.

James