Engine Light On But No Diagnostic Codes
 

Recently, I replaced the rear rocker box cover gasket and the PCV valve underneath of it. During the process, I had to unhook some electronics in order to get the rocker box cover off. After I replaced the gasket and put the cover back on, I hooked up all of the electrical connections again.

Now, occasionally, the engine light will come on when I ride Talulah but will go out again after 5 to 15 seconds. So, in order to get a sense for the reason for the engine light, I checked the engine codes through the speedo.

This is a pretty straightforward process: turn the power off to the bike, press and hold the button on the back of the speedo, turn the power back on and then release the button after the "diag" message clears from the speedo.

Unfortunately, when I go through the process of cycling through the various subsets of diagnostics, I get no codes. In fact, I get either "None" or "No Rsp", usually followed by the part number for the speedo.

This process has worked before and produced codes. A while back when I was having problems the my TSSM, I was able to get some diagnostic codes out. Now, however, I get squat.

So, short of taking it to the dealer, how would I go about remediating the engine light issue and the lack of diagnostic codes?