So Ive done lots of aftermarket interior modding to my car, and all my previous cars. Never had a problem never faced any issues. In my RX8 I have the metra double din kit running a carputer, and I also have 3 Prosport gauges grabbing power from the same source as my carputer.

Ive had the setup up and running for about 4 months without any problems, until this morning. I turned the car on and only one of the 3 gauges started up and the backlight for the dash LCD display didnt come up. At first I thought it might be a loose wire but after a bit of thought, I realized it couldnt be. All my gauges are soldered together to the same source, and why would the backlight go off?

Then I went to fix my sideview mirrors and they wouldnt move. I noticed that whenever I tried to move them, the only working gauge went on and off, and the lights on the A/C Buttons went off as long as I was holding the mirror buttons down.

Also, I noticed that while idle, if I revved the engine the backlight on the LCD display would gradually get stronger and then weaker again when I took my foot off.

At this point im thinking its probably a fuse problem, but Im not sure. Any idea's??

 

Surprised no one has replied yet, but I solved the problem.. Surprisingly it was a fuse. I would have thought that if a fuse went out I would loose total power running to that line. Im not sure why or how I DIDNT loose all power, and still vaguely had some instruments working. But yeh, it was the 30amp ACC fuse by the pedals.

 

sorry just saw it, but the one that was working may get its source from the illumination and ave a crossover inside the gauge. or power is backfeeding from something else. I have seen things like this happen before, only small consuming things turn on....lol

 

Fuses can partially blow too. Test the faulty fuse with a multimeter. Does it show open? Or just like ~300k ohms resistance?

Also, this forum isn't as active as you may think. Not shocking someone didn't respond within 5 1/2 hours. Especially on a problem like this where you have modded the hell out of your electrical system.