Hello all, I am hoping someone out there can help me out. Just got done rebuilding my sons 2000 civic dx. Currently the speedo, the fuel, and temp gauges do not work (they didn't work before rebuild) , as well I get no communication with the ECU when plugging in a OBD scan tool.

In my research all the 2000 civics all came with OBD2b. However this car has OBD2a as a main harness and ECU. My question is, is there a difference between the OBD2a and OBD2b dash harness? And how do I tell what it is? I assume that only the same harness would plug into the ECU. I really need to get these gauges working. Ive been trying to trace the wire off the Speed sensor to at least get that working, with no luck. I am at the point I want to just scrap both harnesses and replace them both. And if I do go that route, does anyone have any leads on some nice upgrade harness manufactures? Thank you in advance for your help.

And if there are any civic tech geniuses that live in Eastern Washington, hit me up, I would love to have someone come take a look at this thing.

 

Did you ever figure this out? I have a similar issue currently, I put a obd2a d16y7 motor, harness, and ecu in my 2000 civic. Having issues hooking up the 2A ecu in the 2B chassis.

 

You are simply doing this wrong... changing the chassis to match the engine harness is WAY more difficult that changing the engine harness to match the chassis. Find an OBD-2B engine harness and modify it to fit the OBD-2A engine... I believe the only item that must be changed is the distributor unless you are willing to modify the engine harness distributor plug to fit the OBD-2A distributor.