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2005 Malibu LS Electrical Problems

Recently I tried installing a fire department 2 way radio in my brothers Malibu. I?m not sure if it was the radio or the car but I instantly blew the radio and a 50 amp fuse that controlled the lights and power options of the car.

As a background I tried tapping a fuse inside the car and grounding it to the metal of the center council near the other ground parts of the car.

I replaced the fuse, but now the car is popping smaller fuses left and right, and a brand new signal light bulb is now out. (So was this a preexisting problem???)

Anyone have any idea on how to diagnose the problem or other things i can do to stop this??

The first step is to remove any wiring and taps you installed, and make sure the insulation on any wires you tapped is repaired to prevent dead shorts.

You didn’t state what the RF power of the radio is but most radio sytems should be tied to power by a fused lead directly from the battery since the power requirement is usually pretty high. The control lead for the radio, if it has one, can tie to a fused lead in the dash fuse panel. I agree with NYBo, you should isolate what you have installed and see what happens then.

“As a background I tried tapping a fuse inside the car and grounding it to the metal of the center council near the other ground parts of the car”. If you literally did what you stated here it sounds like you grounded the fuse but I assume you mean you grounded the radio case. If other fuses are now blowing then it would seem something has been damaged by this installation. I can’t explain how that or the light would get damaged unless some voltage in the radio got connected to the cars power system somehow or the RF power output got involved.

As a installation tech for Motorola (2way FM police,fire etc,) I always isolate my equipment from the vehicles electrical system,worked out good.One thing about F.D. comm. equipment they wanted evervthing to come on with the turn of one switch.The radio’s on/off were wired on and all they had to do was move a high-amp capable mechanical switch and everything came on.(Switched the ground side).I have no idea what your getting at with your "as a background…"statement.Does the radio smell burned (did you let all the smoke out of it?)

The radio does not smell burned, there was 1 little wisp of smoke from the wire. The however has tested as DOA. (It was a well used m1225)

The car was immediately restored, the pig tail fuse removed, the ground replaced, and the nearby grounds checked.

Since I popped a 50 amp fuse under the hood, that controlled the radio aux power windows signal lights, and the fuses that blew since were independent of that, like aux power etc, i have a feeling the fuses just didnt blow with the big one and went later.

Any ideas are appreciated!

You need personal help with this, magnum771. Use a digital voltmeter, and the POWER DISTRIBUTION wiring diagrams. You may be able to get these through your local library’s online subscription service (I do). They may have ARRC and Ask a librarian at the Information Desk. The other approach is for you to unwrap every wire bundle and individually inspect each wire. It’s not impossible, just takes (a lot) of time. Choice.