Mechanics

RADIO, ENTRY LIGHTING AND CONSOLE LCD STOPPED WORKING

2004 Mazda RX8 • 62 miles

Last Friday all was well. On saturday, I noted the radio, entry lighting and console LCD (temp, clock, etc) stopped working. I suspected a fuse changed it and powered the system. The fuse blew. Tried again and the 15amp fuse blew.
All other electric works. OH the check engine light came on, too.
ANy ideas?
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Heartzinaz
June 18, 2012.



A simple trick to finding a short is to replace the blown fuse with a pair of spade terminals, then use small jumper wires to connect them to a 12 volt light bulb. A brake light bulb works well. When the circuit is live and the short is present, the bulb will be full brightness and hot so be sure it's not laying on the carpet or against a plastic door panel. Now you can unplug electrical connectors and move things around to see what makes the short go away. When it does, the bulb will get dim or go out.

Caradiodoc
Jun 18, 2012.
Thanks. I'll check it out.

Tiny
Heartzinaz
Jun 18, 2012.
Gotta leave for a few hours but will check back later tonight.

If you have courtesy lights on the doors, check for frayed wires between the door hinges. The fuse - test light may go dim when you open or close the door if there's bare wires touching there. Also look for anything stuck in the cigarette lighter socket. They are often on the same fuse. If you have an aftermarket radio that had the wiring spliced and taped with electrical tape, that is very unprofessional. The tape will unravel on a hot day and the wires can short together.

Caradiodoc
Jun 18, 2012.
It's the darnest thing. All of a sudden NO soor lights, no radio, no console temp/clock, etc. Wish I could afford to sell this. It's not the quality I am used to in Japanes vehicles. Last fall the steering harness failed! 2K$ later. It must be this hot arizona weather.

Tiny
Heartzinaz
Jun 18, 2012.
Forgot to mention - the fuse slot is electrically hot. I put a fuse in it and touched the case. Zap small spark. I pulled the main fuses under the hood. Loaded a new 15amp one. Returned the mains opened the door. Tester said fuse was bad. Visually confirmed. I will check the door wires. Not clear what else. Unless the dealer did something stupid.

Tiny
Heartzinaz
Jun 18, 2012.
Use my light bulb trick instead of the fuse. When the fuse blows, all you know is there was a short but you don't know when it blew or what you were doing at that instant. With the bulb, you won't have to keep on wasting fuses and you have a visual indication when the short is present and what you're doing or moving when the short goes away.

Caradiodoc
Jun 19, 2012.
I found a short in the right sun visor. It was the only thing I could think of. All other wires are covered with protective casings.
Removed the short and loaded a new fuse. It works.
Thanks.

Tiny
Heartzinaz
Jun 19, 2012.
All right. One in a row!

I actually had that same thing on a Chrysler Fifth Ave. Many years ago. The wire had cracked insulation where it came through the pivot. When you hit the brakes, the looseness in that pivot let the visor move forward less than a quarter inch but that was enough to blow the fuse feeding the vanity lights in the mirror. Hit the gas and the visor moved back and the short was gone. Took nine visits to our shop before I found it.

Happy yours is solved. Did you use my light bulb trick?

Caradiodoc
Jun 19, 2012.