Isata 5 LED lighting issue

[random_james]

So, day before yesterday our front (labeled "Front Ceiling" on the touch panel and the Cabover switches, labeled "Entry Lights" on the switch set beside the door) LED ceiling lights stopped working - both bulbs at once. I got around to getting my meter out tonight to see what was going on, and that's when things got *really* odd. I double checked on a working light, and got what I expected on it - 0 volts when turned off, approximately 5 volts when turned on. On both the non-functional LED lights, I have a constant -7 (yes, negative 7) volts, whether they are turned on or not.

The multiplex system believes they are on, and no fuses are reading as bad on the display under the bed.

Anyone have any thoughts about how this could happen? I'm starting to worry that I've got something bad somehow shorted on to that LED circuit...

[bclemens]

I'll ask around.

[bclemens]

First response

"These are negative switched, so to properly check, he needs to put the + lead on the positive wire and the negative lead on ground, he should have 12V. The negative wire can be checked with a continuity to ground, when the light is on, the continuity should be very very low. When Off it should be open or really high"

[random_james]

OK - tomorrow I'll check V+ to ground, instead of V+ to V-. Another interesting thing though - today I pulled the fuse (F1, according to the panel under the bed - is that the correct one?), and I'm still seeing the same voltage (-7v) across V+ to V- on the LED light board.