Red light comes on and blue light comes on and no sound I have disconnected the speakers and input on my APX 4240

• Check that the transmitter AC power adapter is fully inserted into the wall outlet and the power cord from the AC adapter is firmly connected to the transmitter power input jack.
• If you're using the speaker power adapter, confirm that it's fully inserted into a wall outlet and the adapter power cord is firmly connected to the power input jack on the speaker.
• If you're using batteries for the speaker, check that they are fresh and inserted with correct polarity (+, -).
• confirm that the speaker is in 900MHz wireless mode-the indicator light on the front of the speaker should be either fl ashing or solid green. If the indicator light is blue, press the ON-OFF / RF-BT button on the back of the speaker to switch to 900MHz mode.
• confirm that the speaker is turned on and tuned to the transmitter-the indicator light on the front of the speaker should be solid green (not blinking).
• Check that the audio source component (stereo, MP3 player, etc.) is turned on and transmitting sound as it normally should.
• Make sure the volume on your audio source is turned up.
• Check that the speaker volume is turned up.
• Make sure you have disconnected the 3.5 mm audio in cable from the AUDIO IN jack.

The Amp in the trunk might have blown,
Town Car Radio Wire Diagram
Car Radio Battery Constant 12v+ Wire: Pink/Light Blue
Car Radio Accessory Switched 12v+ Wire: Yellow/Black
Car Radio Ground Wire: Black/Light Green
Car Radio Illumination Wire: Light Blue/Red
Car Stereo Dimmer Wire: Blue/Red
Car Stereo Antenna Trigger Wire: Blue
Car Stereo Amplifier Location: Trunk
Car Audio Front Speakers Size: 5? x 7? Speakers
Car Audio Front Speakers Location: Doors
Left Front Speaker Positive Wire (+): Orange/Light Green
Left Front Speaker Negative Wire (-): Light Blue/White
Right Front Speaker Positive Wire (+): White/Light Green
Right Front Speaker Negative Wire (-): Dark Green/Orange
Car Audio Rear Speakers Size: 6? x 9? Speakers[img src="http://www.assoc-amazon.com/e/ir?t=modilife-20&l=as2&o=1&a=B00009UHRE" width="1" height="1" border="0" alt="">
Car Audio Rear Speakers Location: Rear Deck
Left Rear Speaker Positive Wire (+): Gray/Light Blue
Left Rear Speaker Negative Wire (-): Tan/Yellow
Right Rear Speaker Positive Wire (+): Orange/Red
Right Rear Speaker Negative Wire (-): Brown/Pink
Check the fuses

wires are crossed. recheck connections

Are you using all five cables? RED, BLUE, and GREEN for the component video, and a set of RED and WHITE for right and left audio. Also try using the audio line of the set top box feeding a set of PC powered spekers just to verify that the box is putting out audio signals.

REMOVE THE RCA INPUTS AND DISCONNECT THE SPEAKERS, THEN POWER THE AMPLIFIER UP WITH THIS NO INPUT, NO SPEAKER LOAD CONDITION. IF IT STILL DOES NOT POWER UP, VERIFY THAT THE POSITIVE AND ESPECIALLY THE GROUND CONNECTIONS, ALONG WITH THE REMOTE CONNECTIONS ARE 100%, THEN TRY AGAIN. IF STILL NOT POWERED UP, MEASURE THE REMOTE WIRE VOLTAGE TO INSURE THAT IT IS NOT LOWER THAN 11 VOLTS. IF YOU CANNOT MEASURE IT, THEN DISCONNECT THE REMOTE LEAD FROM THE AMPLIFIER AND TEMPORARILY INSTALL A JUMPER WIRE FROM THE POSITIVE POWER TERMINAL TO THE AMPS REMOTE TERMINAL WHICH WILL FORCE IT TO TURN ON. IF IS STILL DOES NOT POWER UP, THEN IT WILL HAVE TO BE SERVICED. LET ME KNOW IF YOU NEED FURTHER ASSISTANCE.....V

Green is sound output
Blue is sound input
Black is for rear channels
Pink is for a Mic
Yellow is typically for a digital input/alternative for optical

I understand that you have tried connecting different audio source to the Receiver as some of the audio source will output only 2 channel audio. I hope you have tried changing the Input mode and Input selector to get the surround sound.
Please disconnect the speakers with the receiver and clean the edges of receiver and speaker cables using solution like alcohol and try.
If the issue persists, please interchange the rear speakers with front speakers and vice versa and check if audio is coming to make sure that the speakers are working fine.
If the audio comes after replacing the speakers but not from surround speakers, the receiver requires service.

This sounds normal. The light comes on when there is 12v supplied to the blue wire (remote input). Need more details. [email protected]

"One has positive and negative input, another positive and negative output (red and black on each)"

Just from your description, it sounds like pos/neg input are the 12 volt pos neg supply for the amp inside the subwoofer. Red is pos, black is neg.

"positive and negative output (red and black on each)"

This sounds like it's used if you want to proved 12 volt pos/neg to another component.

"and a third wire with left input right input positive and negative (blue, red, yellow and black)"

This is for the cables coming from the "subwoofer out" on the amp. This is 4 wires altogether -- correct?