Hi everybody, long story but I need your help with my Xterra 00, like 6 months ago I got the service engine soon light, after I scanned my Xterra I got the P1605 code, however my Xterra runs good like nothing happen. I tried to clean this code many times but this same code comes when I just turn on the key and this happen not all the times, I mean I clean the code and 2-3 days or 2-3 weeks after when I just star my car the service engine light comes with the same issue. Based on other people recommendation's I check continuity between the ECM and TCM to find an open wire issue but everything looks fine, even I bought another TCM and I got the same issue. If any of you guys could have an idea about what is wrong I really appreciate your help. Thanks

You dont by chance have a "remote start" installed do you? If so it might be worth checking things with that first. Also have you checked all the related connections you can reach, make sure they are clean, making contact, no wires melted anywhere. anything else you might have installed aftermarket, or other work you might have had done around the time it started happening.

Long time ago I fixed this issue and since that I didn't visit the site however I want to share the solution and pay back to the XOC.
The problem that I had was the ignition switch Assembly since the P1605 just come up with the ignition signal I mean I didn't start the engine and the P1605 came up replacing the ignition switch assembly resolve this issue, hope this help to anybody with the same issue.