I can't figure out how to get pics on here, but I have an ecu that has 4 plugs on it. One 26 pin, one 16pin, one 12 pin, and one 22 pin, in that order from left to right. It has a foot long section of the harness still attatched to it.....serial number on it is 37820-P72-901803-100565. The writing on it says its a b18c auto ecu, not sure about the year tho. I think its obd II but the wires dont match for the pinouts i've found. Plus there are for plugs, and the auto might factor in too. Any ideas on how to figure out these plugs and pins ? JDM pinout? schematic or something......any help would be great......thanks........
JDM ecu? GSR swap
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and its a US OBD1 P72 (and i concur on it being an auto ECU)
before me and will get into a shouting match, im gonna cite my sources
https://hondaswap.com/forums/index.php?showtopic=61473
before me and will get into a shouting match, im gonna cite my sources
https://hondaswap.com/forums/index.php?showtopic=61473
okay so the most important part of the SN is 37820-P72-901
now the last 3 digits are 901. Where's the 'A'??? it's JDM and it's Manual... (and OBD2)
Yeah, I think you're misreading the chart there, dude...For starters, it can't possibly be USDM. The GSR was not offered with an automatic transmission in the United States.
Now, back to the ECU code...
37820-ABC-XYZ
ABC-Engine ECU designed for
X-Market of ECU
Y-0: 5-speed, 5: Auto
Z-even number: "11F0" board, odd number: "1720" board
Markets:
Axx-USDM 49-state
Lxx-USDM Cali Emissions
xxx-JDM
Jxx-JDM
9xx-JDM (auto)
Gxx-EDM
Qxx-Oz DM
Cxx-Canadian
Nxx-usually factory reprogrammed, no particular market
----
Now, the code on his ecu is 37820-P72-901. 9=JDM auto, but 0=5spd. That's weird...I'm really not sure what to think of it. However, the OBD1 auto ECU's only had 3 plugs (like the 5spd-this is why there's some confusion with people running auto p28's). The only 4-plug automatic ECU was the OBD2's. I'm gonna go ahead and stick with you having an OBD2 JDM automatic P72, and you can't use it.
Now, back to the ECU code...
37820-ABC-XYZ
ABC-Engine ECU designed for
X-Market of ECU
Y-0: 5-speed, 5: Auto
Z-even number: "11F0" board, odd number: "1720" board
Markets:
Axx-USDM 49-state
Lxx-USDM Cali Emissions
xxx-JDM
Jxx-JDM
9xx-JDM (auto)
Gxx-EDM
Qxx-Oz DM
Cxx-Canadian
Nxx-usually factory reprogrammed, no particular market
----
Now, the code on his ecu is 37820-P72-901. 9=JDM auto, but 0=5spd. That's weird...I'm really not sure what to think of it. However, the OBD1 auto ECU's only had 3 plugs (like the 5spd-this is why there's some confusion with people running auto p28's). The only 4-plug automatic ECU was the OBD2's. I'm gonna go ahead and stick with you having an OBD2 JDM automatic P72, and you can't use it.
The civic its going into was automatic, and its gonna stay that way. I have a b-series auto bolted up to the engine already........not sure if its actually a gsr auto tranny, or just an LS or something, but I'm lead to believe its all Japanese, cause a seperate harness was sent (besides the foot long cut section that came with ecu) and that harness has the shock tower plugs backwards, like for right hand drive. I figured it was a JDM ecu. Even the pin numbering is backwards, pin 1 is on the top right, instead of top left. I believe they read that way over there, right to left? Anyway. If it is a JDM ecu, I still have no clue on the wiring. The OBD II wire colors dont match with any of the pin numbers, even when looking at it backwards. Thats why I'm trying to track down another pinout or diagram or schematic or something. I'm not sure where to go from here. Thanks again for the help.
You aren't gonna be able to use that ECU.
What you need to do (if you haven't already) is wire up the engine with the wiring harness that came stock in your car. You'll have to do a little wiring, such as change the inector and distributor plugs, but nothing major for the most part. You CANNOT use the JDM engine harness with your car, period, end of story. Then find yourself an OBD1 auto ecu, and just plug it in.
What you need to do (if you haven't already) is wire up the engine with the wiring harness that came stock in your car. You'll have to do a little wiring, such as change the inector and distributor plugs, but nothing major for the most part. You CANNOT use the JDM engine harness with your car, period, end of story. Then find yourself an OBD1 auto ecu, and just plug it in.
sigh...
No. you can't use a JDM harness in a USDM car. Period.
No. you can't use a JDM harness in a USDM car. Period.
No.
Because it's OBD2 and your car is OBD1.
The problem is not that you have a JDM ecu, it's that you have the WRONG YEAR ecu. If you get the right YEAR ecu, it doesn't MATTER if it's JDM, USDM, CDM, RDM, whatever.