I have a 4 door 2004 V6 Accord - I'm getting a P0685 code so I got a new Engine Control Module (ECM) power relay which I'm hoping will fix it. Before I start tearing stuff up though, anyone know where in the car this relay is physically located and about how hard it is to get to (ie how long it will take to change)? I'm finding lots of fuse diagrams on the internet but no where that shows where the relay is actually located... thanks!

 

DTC P0685 can be caused by many other things other than the main relay 1.

See the attached Honda job aid PDF file.

Anyways, to answer your question, PGM-FI Main Relay 1 is located in the under-dash fuse box.

 

Thanks! I know there could be other things causing that, but I figured I'd try the simple stuff first.

 

 

Yeah it fixed it. Car seemed to shut off at random times.