I have a 1998 civic with a 1994 gsr engine/ecu. The civic harness is used and I have a premade jumper plug (the $20 version you can buy on ebay etc.) to go from obd2 harness to my obd1 ecu. I am getting code 6. I have replaced the sensor and ecu and still have the code. My sensor is reading around 2000 ohms. I have read a bunch of threads and it seems like the wire should be 5v. Mine is reading 12v with wire unplugged from the sensor and key on.

Anyone know why it's 12v?

How do I get it to the needed 5v?

What else am I doing wrong here?


Thank you

 

Check continuity of the red/white wire between the ECT sensor and the ECU. Then make sure the green/black wire is a ground.

 

Do you have the original OBD2 ECU? If so plug it in and see if the code goe away. This will isolate the problem to the harness or OBD1 ECU

 

I will check the continuity and ground. Thank you

 

I do not have the obd2 ecu. I bought the swap this way. Good point though...

 

This was very helpful, thank you. I had the wrong plug on the ect. I didn't do the swap so not sure of all the schematics. I appreciate you mentioning wire colors b/c that's what clue'd me in. Silly mistake but glad it's fixed!

 

Did you have the vtec pressure switch on there?

 

Glad you found the problem... always happy to help.

 

Yes. Whoever did the swap made the harness to where the correct vtec pressure switch plug doesn't reach so I assumed I had it correct b/c one reached and the other didn't. Lost a lot of time on this but at least it's corrected now.