Car Stereos: 2300htc audiobahn amp, using a digital multimeter, ac volts

Question
I have a 2300htc audiobahn amp. And everything works the lights light up the fans come on everything. But no sound comes out of the amp. my speakers are hooked up right i just don't know whats the problem. It don't say its protect mode or nuttin.

Answer
Hi Shawn,

It's really difficult to say where the problem is in a case like this.  I can tell you how I'd troubleshoot the problem.

When you have an amplifier that's not producing any sound, you have to determine whether there's an audio signal present at the input jacks, and whether there's an audio signal present on the output terminals.  Generally, I'll do this using a digital multimeter and a small test amplifier.

An audio signal really just consists of AC voltage.  As the audio gets louder, the voltage gets higher.  I'd start by disconnecting the speakers from the amplifier, then set the meter for AC volts and put one probe on a negative speaker terminal, and the other on a positive terminal. (I'm talking about the speaker terminals on the amplifier, here).  Turn on the system and turn up the volume; see if there's AC voltage present that increases and decreases with the music volume.  This works best if your meter has a bar graph display; you can also use an analog meter (the type with an actual needle).  If there's AC voltage present on the terminals, but no sound from the speakers, then the problem is in the speakers.

If there's no voltage on the amp's speaker terminals with the music playing, then you need to go back to the RCA plugs attached to the amp.  You can test these for AC volts the same way, placing one probe on the RCA plug's center pin, and the other probe on the outside shield conductor; but the voltage reading will be much lower.  I prefer to use a small, battery-powered amplified speaker that I bought from Radio Shack just for this purpose.  If there's an audio signal present on the RCA plug, then that narrows the problem down to the amplifier.  On the other hand, if there's no audio signal at the RCA plug, you may have bad RCA's or a problem with the head unit.  

Hope this helps!

Brian