ODBII Connector for 95 NSX T where?

[Linklogical]

Stephen, it was definitely custom mounted with some fun zip ties and that aluminum bracket like you mentioned. Just wasn’t sure if the connector itself was factory but the more I look at it, the more it was someone’s headache in the past. I’m sure yours and others post’s definitely helped him out and saved me some trouble (thank you). Now I just have to make a new bracket and find a new home for it.

 

[Stevon]

Stephen, it was definitely custom mounted with some fun zip ties and that aluminum bracket like you mentioned. Just wasn’t sure if the connector itself was factory but the more I look at it, the more it was someone’s headache in the past. I’m sure yours and others post’s definitely helped him out and saved me some trouble (thank you). Now I just have to make a new bracket and find a new home for it.

Linklogical,

My problems were unique I had a 1991 frame totaled doner car and purchased a stripped 1995 T chassis, changed the color from black to 2006 Corvette, Red Jewel Tricoat. Took the drive train and entire interior, exhaust, engine and installed it into the 95 T chassis to make a functional car. That was a great challenge the 91 NSX was throttle by cable and the 95 was throttle by wire like airplane controls. The guy I bought the 95 chassis said just butcher the 95 harness and install the throttle cable. Decided to keep the car all 95, wire harness, throttle by wire servo motor controlled throttle body, emissions, etc. To do this I decided to change the 91' engine intake manifold to 95 version including servo motor controlled throttle body and the 95' engine wire harness. My problem was emissions, couldn't pass them and couldn't figure out why also the car ran like crap. Went to an Acura dealer and wasted diagnostic charges, a private NSX specialist ($400) but no one could figure it out. The car was not registerable in CA at least. Had to figure out what the problem was myself learning ODBII emission systems along the way. Fuel trim short maps, Fuel trim long maps, NOX, HC etc. There was no easy way to get to the ECM data and what the car was doing. After research I realized that the connection to it required only 4 wires to function. After I found a way to get access through them collected pages and pages of data but had no idea what I was looking at, more research and found disconnecting the battery (clearing fuel map) then running the NSX bank 1 was getting leaner and leaner but bank 2 was getting richer and richer, this made no sense, no wonder I couldn't pass emissions. After talking to folks, research and pulling my hair out I had an idea, what if the oxygen sensors were reversed or cross connected somehow? I thought but no, Honda would not use the exact same connectors for both banks, right? I said to myself what the hell just try to swap them. Honda did use the same connectors for both, swapped connections and wala, all of the emission problems were solved! 6 months of trying to fix and register my restored car actually succeeded! There were other electronic problems to solve, electric power steering failure, SRS system, on and on. The project took 9 years but looking back, enjoyed the challenge more then actually driving the car! This project was all pursued when I was single by the way.

 

[I_M_Legend]

Hey Prime. I know this is an old thread but I ran into this same problem when taking my car apart. I couldn’t any reference to what this plug is in the search or the manual. Only thing close was a C425 that lives in the center console for automatics. Does anyone know what this is for? Same color wires and pinout Stevon posted. Mines a 96. Thanks

The plug in your picture if for keyless entry.

 

[Linklogical]

Stevon, talk about a build; awesome and amazing work. That must of been a major headache and such a reward at the same time. I can relate with the challenging part that makes it fun. Sometimes we get into project that looks like there is no way out but congrats on sticking to it and seeing it through.
Good find in reversing the plugs and thanks Honda for making it fool proof. Haha

@I_M_Legend, that would make sense too since my ODBII harness is already ran. Thank you.

 

[Old Guy]

For me the pinout of the DLC connector did not work with my scanner, Honda for some reason uses a different choice of pins to access the ODBDII data. I made an adapter that uses the standard SAE pinout used by most OEM car manufactures to work with my cheap standard multi car make scanner. There are Honda specific scanners that work without the modification on all Honda vehicles with Honda DLC connectors in their cars

Stephen
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I think the Honda diagram is the standard J1962 connector, it is just left - right mirror imaged looking from the back of the connector. The J1962 standards document specifies numbering looking from the front of the connector. What is goofy (in skate / snow boarder speak) is the pin numbering scheme. Honda lists 1-8 on the bottom; but, the J1962 standard lists 1-8 on the top. So, Honda's K line, +12v and the two grounds are in the correct physical locations to match up with J1962; but, the numbering is goofy. The J1962 standard assigns pin number 7 to the K line while the Honda ETM assigns pin number 15 to the K line.

Standard diagnostic scanners do work just fine with the J1962 connector on my 2000 NSX. I have never checked the connector to see if the pins are physically numbered. If they are not numbered, then the connector is probably J 1962 compliant and the goofiness is just reserved to the service manual and Honda's way of numbering cavities in the connector. What is particularly goofy is that for the 16 pin connectors used elsewhere on the car wiring harness 1-8 would be on top so Honda deviated from its own numbering practise and the J1962 standard when it comes to placing 1-8 on the bottom of the diagnostic connector.

 

[Stevon]

Linklogical,

Yeah, it was a blast! Since My NSX was a "frankenstein" project to begin with, took some liberties on the rebuild. Changed the body color, added Ferrari emblem as a joke (NSX Pininfarina body) , dressed up the engine, modified original engine cover into a mesh engine cover (not available for a NSXT) painted the calipers, rebuilt the control arms with aftermarket parts, etc. I even traveled to a Mexican factory to have custom silicone hoses made for the NSX, wanted 100% silicone kit but none were available so I found a way to have my own set made! I have gotten flak about changing the original NSX color and the Ferrari badge but this car was a collection of parts! 91 Engine, trans, interior in a 95 NSXT body. Well I finally grew up and settled down, my NSX is gone, sold to Serge from LA and I bought a house in Imperial Beach for my new family.

Stephen

, talk about a build; awesome and amazing work. That must of been a major headache and such a reward at the same time. I can relate with the challenging part that makes it fun. Sometimes we get into project that looks like there is no way out but congrats on sticking to it and seeing it through.
Good find in reversing the plugs and thanks Honda for making it fool proof. Haha

@I_M_Legend, that would make sense too since my ODBII harness is already ran. Thank you.