Dan's PNP RB25DET R33 Skyline ECU PCB

[Dan]

Yeah i want to keep the protection, i like it

Ditto on your thoughts on the filter too great minds !

[Dan]

Introducing the Nissan R33 GTST RB25DET OEM ECU in all it's intimate glory..... (excuse low-res image quality)

[Dan]

I now have all the measurements I need to draw up the PCB to ensure that it will fit inside the factory enclosure

Will post up the initial PCB dimensions with header when it is drafted up in Altium

[Fred]

What are the 6 big resistors, 6 matching caps, and 6 small resistors, outputs to the ignition by chance?

[Dan]

Yep I think they were for the ignitor drives good guess!

[Fred]

Fucking funny that, isn't it! Get the values ;-)

[Corbon]

Rob, please tell me that you don't fit the Skyline+Auckland stereotype

Haha, I wish I was that cool. I don't have my seat tilted back and drive around in second if that's what you mean.

Corbon - great stuff. Please share your pinout information and we will go from there welcome aboard!

Thanks, have attached a pdf containing the pin-out as tested on my car a few months ago.

In the OEM ECU the small resistors and caps connect with the injector output pins ( high current/chunky pins in the right hand group ). There is also a dedicated 'fly-back return to battery' pin amongst that group too so I presumed those components had something to do with that.

The big resistors each connect to the ignition outputs but appear to be all common at the other end so my guess was they form some kind of drive for the ignitors which is switched to ground when off. Seems weird though so I'm probably wrong.

Good work on finding the connectors! Will be interesting to see what they are worth.

The OEM set up is probably more than adequate but for the CAS inputs had you considered using the same set up as RavAGE: MAX9926? Seems to work well on my desk with a pull-up on the +IN and -IN floating. Maxim also does a hall effect conditioning IC which from memory measures the current going through the opto/hall instead of diffing the voltage. Could be worth a look if you guys hadn't seen it.

Edit: MAX9621 Hall Effect Sensor Interface Link: http://datasheets.maximintegrated.com/en/ds/MAX9621.pdf

[Fred]

MAX9926 etc are sub-optimal for logic signals like this even when setup properly, which I assure you, you did not do. The OEM is more than just adequate, it's superior to the max99xx setup. Abe has a rant thread about his Mazda input circuit somewhere. Dig it up and have a read.

The hall interface linked is for a raw hall sensor. The typical "hall sensor" uses hall effect, but conditions the signal in the sensor and returns a logic or open collector output just like opto sensors such as the Nissan ones.

Re JAFA+skyline, skyline drivers are usually wankers, the annoying arrogant sort of JAFA that would never dream of letting you into a gap. I had a skyline in Auckland too... but I was always going way too fast and/or sideways to be letting anyone into a gap ;-)

Fred.

[Dan]

Yep, Fred is correct here Corbon, the MAX IC is not a good candidate for this task.

I am drawing up the PCB dimensions and creating the connector footprint in Altium tonight.

[Corbon]

Nice to have some feedback Some interesting reads re: OEM inputs.

Was Fathers Day today so got time to go outside and crawl around under the car. Confirmed that the neutral switch and exh temp sensor are buggered/bad connection but do connect back to the ECU pins the service manual reckons they do. Just the OEM diagnostics pins I'm unsure about now. Are they likely to be utilised?

Fred: I can't fully deny being a wanker but can tell you now that I drive like a wuss.

Dan: Can Altium import DXF? I have the connector and enclosure drawn up if it could be of any use to you.
I have done all my previous work in a program called Easy-PC. Unsure if any other progs can open it's standard .sch and .pcb files though.