I am very, very pleased to report that the MSTR WARN dimming is finally working.

I purchased Zener diodes with two different values on Friday, and tried them both in my jumper-wired proof of concept. I selected the one that gave the best balance with the other annunciators lights, and did the wiring mod to put it in the circuit. It works perfectly.

I have invested much more time and thought in the annunciator lights than I had expected, and I have drawn two lessons from this saga. The first aborted effort was triggered when I was told that 12V bulbs for the Vivisun annunciators I used were rare and very expensive. I was told that I would need to acquire a 24V to 24V DC-DC converter, and a particular one was recommended. I took this advice at face value, and ordered the recommended converter, only to discover that the recommended mod to the converter involved replacing microscopic surface-mount components, which was well beyond my capability. I then e-mailed Vivisun to inquire about 12V bulbs, and found that they were readily available. Vivisun's price was a $5/bulb, but other vendors had them for much cheaper.

Lesson #1 - Don't make big decisions based on information from a single source, if possible.

My second mistake revolved around the way the MSTR WARN annunciator worked. I had noted that the sample wiring diagram provided for the Engine Monitor had the MSTR WARN lamp wired in a strange way. I studied that drawing, could not understand it, and decided to ignore it. Later on, after first wiring up the MSTR WARN lamp, I noted that it was always ON, rather than flashing as the instructions suggested it should be. I assumed that the instructions were perhaps out of date. Of course I eventually learned that the wiring diagram provided for the Engine Monitor was correct, and that the lamp would flash if it was wired correctly.

Lesson #2 - Pay attention to discrepancies. If something doesn't match up there is probably a good reason, and the sooner you find it the less grief it will cause you.

Here is what the annunciators look like without power.

Here they are with the MSTR WARN and the LOW OIL PRESSURE annunciators illuminated in BRT mode.

And here we have the same two lit in DIM mode.