Recently I found out that although my RB25DET powered car has a factory skyline loom, the Diagnosis, or Consult port was not in the car. This has something to do with the part of the loom not being required because it is attatched to the body control module.....or something. This was slightly annoying as I had just gotten a shiny new toy that displays what all of the factory sensors are doing, and uses this plug to connect to the ecu....Please excuse the photos, I had to use my phone to take them This also applies to anyone wanting to use a consult cable/software package, or anyone wanting to take a car with a problem to a workshop for diagnosis. Anyway, after making a few calls it seems that not many engine conversions have this port, unless it was specifically though of at the time of the conversion. So here is a list of what you need to make your own factory style diagnosis port. 1-Soldering iron with a fine tip (Preferably with temp control too) 2-A Nissan diagnostic port (found in most 89-96 Nissans, usually located near the drivers knee, just above the fusebox inside the car.) Most wreckers will be able to help you there. 3-some wire that is a similar guage to the stuff coming out of the plug so you can extend it sufficiently. (preferably colored the same as well!) 4-Heat shrink 5-The following link (for the pin locations.) Fortunately there are only 5 pins you need to worry about (The One Marked CHK was not needed for the greddy unit, but you may need it for consult. It's Pin 47) http://d1nz.org.nz/forum/viewtopic.p...cc005368ab3525 (http://d1nz.org.nz/forum/viewtopic.php?t=12720&view=previous&sid=ccdccd73502d978d19cc005368ab3525) 6-Small cable ties Start off by removing the ecu found under the passenger side kick panel. There will be 1 or 2 screws holding it to the body, and a bolt holding the loom in.. Then you need to open up the ECU to expose the inside of the corresponding pins that you will need to tap into being 21 & 22(diagnostic RX/TX) ,31(CLK), 45 & 50 (IGN/- or Pos/Neg) & 47 (To be sure-CHK) Some of these numbers are visible inside the board and are usefull for working out which angle you are looking at! Be sure to double & triple check that you have these right!!!! There are four main screws and a few for the mounting points At this point it would be a good idea to make your extensions to the ports wires. Where possible use the same colour wire, heat shrink and cable ties to make it neat and easy to relate to the correct pins. I also spliced the power and earth cables for a future Fuel piggyback install. If you do this, be sure to insulate the bare ends. Ok, heres the fiddly bit. Solder the wires to the corresponding pins so that they end up pointing upward. This can be a bit tricky unless you have three hands, because you want to try and get a solid connection quickly so as not to melt the plastic around the pins. Fortunately all but one of the pins are on the outside (look inside the ecu & you'll see what I mean) & so access is fairly easy. For the one that isn't (31) you can solder your wire from the other side of the board, on to the circuit board itself, and thread the wire through the conveniently placed hole to the other side. ALWAYS TAKE CARE TO MAKE SMALL NEAT JOINS THAT DON'T TOUCH EACH OTHER as they're all pretty close together in there. (Note I didn't have any black wire so I used the white stuff for my earth as well) Now just neaten all the wires up with some small cable ties. I separated the spare power/earth ones and put a small amount of heat shrink on the ends. You will also need to make a small opening in the ECU cover for these wires to come out of. I used a dremel to grind away a small section on the edge of the lid. If you do not have a small rotary tool of some sort you may be able to use a drill and some files?? Then just finish off putting the covers back on and install as per the reverse of step 1 & voila! 1 Diagnostic port equipped VL You could, of course, tap into the loom itself but that option just seemed too messy and somewhat difficult! MAKE SURE YOU HAVE THE ECU EARTHED i.e. SCREWED BACK TO THE BODY OF THE CAR BEFORE TESTING YOUR WORK! I'm not sure if or what kind of damage you could expect, but it wouldn't be helpful. Not to mention the ECU won't work properly regardless. You can see a couple of the functions of this greddy unit below, and if you have consult you will be able to Data log for longer and more accurately, and have a better display, but this little Informeter is a handy little portable device that can be installed quite neatly to most cars and it has a sh1t load of useful display/logging modes. Can be had for as little as $270 delivered. I hope some of you will find this helpful. Let me know if you feel I have left anything out or would like more info. I'd be happy to help Some original photos have not been recovered yet.

Good write up mate, ill follow this when i get around to doing mine. cheers

brilliant write up mate, saved me heaps cheers!

Thanks. I'm Glad to be able to contribute something guys!

Updated

would this work on a RB30ET?

Not as such, no. This style plug is specific to 89-96 nissans, and the ecu is completely different. There may be another way of doing it that I'm not aware of though....

can anyone please help no i have put the rb25 motor in my vl and now im starting on the ecu and in the old rb30 there are two plugs that go from the ecu and up under the dash behind the glove box and one plug is blue and the other is black and can anyone help me out by telling me where each wire from the plugs go into the new rb25 ecu? or even a diagram or something anything i have searched everywhere but nothing please help anyone

Enjoyed the write up, but if i can make a suggestion. bring the camera back a bit and zoom in, it's better to have a clear shot, than a close blurry shot. excellent find though. glad you took the time to inform all of us. Cheers

I did that. My camera is crap Some original photos have not been recovered yet.