Audio Systems: Audio, digital voltmeter, analog type

Question
I have a 2004 chevy 2500 with the Bose audio system and it sounds like the amp has stopped working, fuses are good i was wondering if you could help me out?

Answer
There are many configurations used by Bose in that model, depending on the body and the engine.  Standard cabs have different installation system from the club cab, etc.

However, for Bose they applied the amplifier in two different ways: One system employs individual amplifiers that are built into the loudspeaker housing.  In this case if only one amplifier goes out, only one speaker is dead and the others should work normally.

In the other case they had one or sometimes two power amplifiers that fed two or more speakers.  In this case if the amp goes out you could lose all the speakers or half the speakers, depending on the amplifiers used and the number of speakers in the vehicle.

So, once you have located the amp(s), the next thing to do is determine if they are getting voltage/power to the battery input terminals.  Best way is to use voltmeter. You can purchase a good such meter for under $10 at Walmart or Home Depot (analog type; stay away from digital voltmeter for automobile work due to grounding problems and misreadings.)

If the amplifier(s) does not have the 12v (both lines) then you must determine why not and where the problem is.

If the amp HAS 12v on both lines (remote power turn-on and main power line) and still no output you must check for bad or shorted speaker(s) or wiring OR no signal coming from the head unit (audio cable broken or pulled out, etc.)  

I have oversimplified the system, but it is adequate for you to do basic troubleshooting and should lead you to the fundamental problem area.

Caution: Bose system are abnormal, i.e., the donot conform to the industry standards and they donot interface with other conventional brand products as a general rule.

Go to crutchfield.com and bose.com both of which have some basic troubleshooting and help guides among their many hotlinks.

Hope this helps; once you get closer to what is going on, let me know if you have further questions.
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