Thursday, As I was returning from another successful test drive of the Sammy's new carburetor, I saw a Jeep broken down in the middle lane of Arapahoe Road near the Saddle Rock Golf Course.
By the time I got the Sammy turned around, other drivers had stopped and helped push the Jeep over to the right lane. I pulled over in front of it to offer assistance, putting on my Sammy's flashers as well.
I walked over, and the youngsters in the Jeep reported help already on the way. So I turned around and noticed that the right turn signal light wasn't working on the Sammy. Hmmm.
Figured it was a burned out bulb, so I disengaged the flashers and went home.
Took the light assembly's lens covers off, saw power going to the socket via a multi-meter so figured yeah, a burned out bulb, even though the filament looked OK.
Three new 1156 bulbs later, no joy. Hmmm. Much diagnostics later, along with a purchase of universal socket 1156 kit from auto parts store, it still wasn't working.
I would read voltage without a bulb in place, but put the bulb in place and no power! Weird.
I called the Sammy guru: Mike W., he walked me through verifying ground connectivity. It was fine. He had me check for power upstream of the cannon socket that provides connectivity to the right lights assembly, there was power, but it would again disappear when a bulb was installed. Weird.
Tiring of this, and quite frustrated by then, I started looking further upstream for a tap point to bypass the wiring harness' wires going to the light assembly.
As I looked, it occurred to me to check the wiring the PO had made to integrate a tow wiring assembly into the Sammy. The Sammy you see, came ready to be towed when I bought it. I'd not used the installed lighting system since the VRRV was set up for just a regular four pole connector instead.
Using the wire's color code, I located the diode involved and removed connections to verify it was indeed the one that would supply power to the rear right turn signal. I put the wires back on the diode and went to check the rear turn signal for power once more; damn if it wasn't working again!
Apparently, my removing connections and putting them back together had been enough to remove corrosion/dirt and allow the diode to function? Or something wonky in the diode? Unsure.
Of course, I was happy at this happenstance, and put everything back together and ensured all rear lights still worked.
The next day, I removed all the diodes, but left the tow wiring leading to the front socket on the front bumper in place. I wired up the respective cables directly to each other for hopefully more reliable electrical connections!
RichardM later explained to me about the diodes' function and a likely explanation of why I saw power via a multi-meter but not when bulb was in place. The meter was likely reading power from elsewhere involved with the flasher lights.