First of all thank you for your responses capsat and GTR.
Now i was digging around for more info on the matter and i managed to find the actual DLC3 pinout for altezza. The pins used in it are:
4 - Main Ground
7 - ISO/K-Line
9 - Tacho
13 - TC
14 - CAN/L-Line
16 - Batt 12+
Which actually arises more questions than it clears, lol. To start off with, there is no pin-5 (sensor ground). If i had to make sense of that i would have guessed that it was prolly strapped to pin-4 (main ground) as there is no way it would work without one regardless of the protocol it uses. Then, what is the CAN-Low doing on pin-14 (its supposed to be an ISO 9141/KWP2k, LOL, and ISO are supposed to have L-line(optional) on pin-15). So yeah its become a bit more confusing now, lol.
The points you raised are valid GTR. If it isn't OBD2 then why go through so much hassle? The thing is that even though it isn't OBD2 it is something akin to it but in complicated JOBD. (No one ever understood why Japanese do what they do and im not claiming to do so either, lol). Nevertheless it still connects to OBD2 scanners and behaves in almost the same manner. You can see live feed off of all the sensors (which is just awesome), tune the engine parameters within the ECU's limit and most importantly, check for OBD2 error codes
and clear them.
The diagram you linked helped clear somethings bro but im afraid its not for the blacktop. If im correct thats a Redtop/Grey top BEAMS schematic since it only shows a SINGLT vvti on the intake cam.I have connected the DLC3 port on my BEAMS in the exact same manner but it doesnt work. I think it needs a Low signal too to initiate the sequence and this is what i cant find. Even then if you could send me the complete diagram to see where all these wires are heading to (the TC one especially) that'd be great.
Im still looking for help and clearing out some of the confusions if possible so please let me know whatever u guys think of the above-said things. Thanks a ton.
Cheers