Seems that in 98-99, Honda had a separate sending unit for the temp gauge, but for 00-02, they didn't use it anymore, just the engine coolant temp sensor (ECT), which was present in the 98-99 as well. What are the temp gauge wiring differences between the two? I looked thru a Haynes manual, and it just showed a separate sending unit for the temp gauge, which is not the case for my 02. How did they get the temp gauge signal in 00-02 models? ECU output from the the ECT?

The sending unit in question is #14.

 

Hey man, did you ever figure this one out? I am just finishing a swap of a F23A into my 2002 Accord Ex 5sp M/T. The engine I pulled was the original 2002 F23A1, which did not use the Coolant Temperature Sending Unit, only the ECT. The F23A I put in was a 1998 (allegedly JDM), which does use sending unit. I'm using the F23A1 EUC, so I'm guessing that it won't look for it, but I'm just wondering how the ECT signal will get to the ECU?