Jensen LXA400 I have had this amp for approximatly 3 years. All of a sudden it will not play any sound. The Amp powers up; the Jensen sign is illuminated as well as the power light. THe protect light remains off. IT powers up and remains on but doesnt play. I know its not a stereo wiring problem because I have a mono amp which the wire pass through the jensen to get to the mono and the mono is still pumping the subs. If the amp done for?

I have this same amplifier. I have noticed several ways it will "not work" during my ownership of it. I have it connected to a seperate battery to save my alternator, battery, etc as it is a power hungry beast for how low the output wattage is. Test the input voltage to see if you have enough, one way to see this is to check the "jensen" emblem that lights up. If you dont have enough power it will appear dim and only the right side lights up. Also the amplifier will not work if your speakers are "blown" even a little bit. Ive taken speakers that wont work on my lxa400 and connected them to a higher power amp and they will work (although they will sound horrible) If youre smart you will keep the gain under 3/4 on this amp, I see some people have found out the hard way that full gain fries the amplifier circuitry. Not an expert on electronics but it smells somewhat like melting glue or plastic. Ive noticed a lot of people have problems with the RCA jacks as well. There are 8 jacks, in two clusters. The first one is A+B and the second is C+D. Note: You do not NEED Y connectors on this amp! Connect your output rcas from the deck to top left and bottom left jacks of the left cluster. This will give you left and right (a+b) output from the first set of speaker outs. Then connect an rca patch cord from the top right and bottom right jacks of the first cluster and connect the other end to the top left and bottom left of the second cluster. This will give you output from the second set of speaker outs. Remember that this is in 4 channel mode. I dont remember the set ups for 3 channel but two channel I believe is the left deck rca goes to top left of the first cluster and the right deck rca goes to the top left of the second cluster. Then you just wire the speaker outs according to the picture on the amplifier. something like this: _________________________ |(+) - (-) +| ~~~~~~~~~~~~~~~~~~~~~~~~~ Speaker + goes to (+) and speaker - goes to (-) Also addressing another issue if you want to increase the wattage to your speakers you just use a lower resistance speaker (2ohm instead of 4) I would not recommend using anything over 4 ohms. As for the high level inputs, I dont recommend using them unless you have the plugs that go with them, its a lot easier to wire your deck rears to a line converter (changes straight speaker wire to RCA jacks) or to just buy a new deck with RCA outs. Last item, common knowledge: 400 watts does NOT mean 400 watts!!! This amplifier puts out very little actual wattage (50 or 83 per channel depending on the load) Hope all this helps someone out there.. Anyone who knows the 3 channel setups I would appreciate it.