Nissan Skyline R33 S2 (1996)

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Corbon
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Re: Nissan Skyline R33 S2 (1996)

Post by Corbon »

That is interesting re: the 12V to ignitors. I noticed the ramp off in the rising edge of the coil trigger signal too. So the "5V logic signal" could be just a Darlington VBE then?

Have attached a similar trace: R33 CYL1 Ignition vs CAS SYNC/POS.
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Fred
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Re: Nissan Skyline R33 S2 (1996)

Post by Fred »

Yes, exactly, and I've been saying this for years (3 of them) and knew the MS2 ignition on my truck sucked badly, but didn't know why until I got my hands dirty and "proved" it. This is nice confirmation from an OEM box.
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Hell Fire
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Re: Nissan Skyline R33 S2 (1996)

Post by Hell Fire »

Yeah, I saw the scope trace and thought that it was 5v out, until I was poking around inside the stock ECU and noticed there wasn't any regulated voltage going to the driver chip for the ignition, just 12v. So all you're seeing is what isn't dropped over the BE junction.
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Re: Nissan Skyline R33 S2 (1996)

Post by Hell Fire »

Did some shitwork on the data collected from the CAS, counted transitions of POS relative to REF.

REF Low->High - POS High
47 POS
REF High->Low - POS Low
73 POS - Cyl1 IGN
REF Low->High - POS High
39 POS
REF High->Low - POS Low
81 POS - Cyl5 IGN
REF Low->High - POS High
32 POS
REF High->Low - POS High
88 POS - Cyl3 IGN
REF Low->High - POS High
23 POS
REF High->Low - POS Low
97 POS - Cyl6 IGN
REF Low->High - POS High
16 POS
REF High->Low - POS High
104 POS - Cyl2 IGN
REF Low->High - POS High
8 POS
REF High->Low - POS High
112 POS - Cyl4 IGN

Total POS transitions in a full cycle of CAS: 720 (as expected)
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Fred
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Re: Nissan Skyline R33 S2 (1996)

Post by Fred »

Reformatted:
Hell Fire wrote:

Code: Select all

47  POS HIGH window
73  POS low window
39  POS HIGH window
81  POS low window
32  POS HIGH window
88  POS low window
23  POS HIGH window
97  POS low window
16  POS HIGH window
104 POS low window
8   POS HIGH window
112 POS low window
Or: 120, 120, 120, 120, 120, 120 :-)

It's not clear to me from the above:

1) Whether this is raw or inverted data
2) What "POS High" means, guessing state of counter track on transition of window track.

I'd have expected a count per window stating whether the window was high or low, and whether this was raw or inverted.

So, is my interpretation correct, and is this raw data or inverted? I'm guessing "yes, and raw".

Fred.
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Hell Fire
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Re: Nissan Skyline R33 S2 (1996)

Post by Hell Fire »

This is raw, and yeah, just the state of the counter at the transition of the window. Doesn't add anything really, was just something extra about the signal I chucked in.
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Re: Nissan Skyline R33 S2 (1996)

Post by Hell Fire »

On a small update, stock RB25 looks to use at least what should be close enough to the standard Denso sensor to match the temp curves already mapped.
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