QuestionHi,
I recently had my car off the road for a few weeks whilst it was being repaired. Everything was working fine until I came to Re-install my Sub and amp. Firstly when i connected the Amp there was a very quiet noise coming from the sub... you could feel a pulse but barely hear the sound. I realised then that the inline fuse for the main live wire to the amp had blown. I replaced this and have power once again in the amp. However there is no sound from my sub. I have checked all fuses involved in the circuits and still have nothing. I checked the connection for the remote wire from the head unit and that is fine.
The only thing it may be I'm assuming is the RCA outputs or perhaps leads...but how do you go about testing those??
Regards
Amy
AnswerHi Amy,
If you're getting a power light on the amplifier, then it's not likely to be a fuse or remote wire problem.
You can test RCA wires with a multimeter set for AC volts. Place the red probe on the center pin of the RCA cable, and the black probe on the outside shield. If an audio signal is present, it will show as a varying AC voltage that increases with the volume music. If you have an analog meter, or a digital meter with a bar graph feature, you can watch it dance in time with the music; but the voltage on the RCA cable will probably be very low.
You can test the amplifier with an alternate signal source, like a portable CD player or MP-3 player. Fit the player with an mini to RCA Y-adapter; this is a cable that has a mini headphone plug on one end, and a pair of RCA plugs on the other. You can connect it to your portable player's headphone jack, and plug the RCA ends into the amp; a working amplifier should produce an output when you use the portable player as a source, just as it does with the head unit.
If you have a head unit with a subwoofer output that can be switched on and off, you might want to check that. If the battery was disconnected on your car, the head unit may have gone back to its default settings.
Hope this helps!
Brian
