91 civic lx stereo problems

The first thing I would do in this situation is go on this site's wiring diagrams. From there you can see which factory wires are supposed to do what. Then I would use a testlight to make sure that the ground, power, and switch wires are working properly. Turn your ignition on and off while testing the switch wire and see if it blinks, if it does than your switch is connected right. The (extra wires youre reffering to are probibly for a power antenna or 12 volt switch to amp. If youre not going to use these trhen cap them off. If they are all working properly then you can see if your head unit turns on. Do a (bench test) with only the power, ground and switch wires attatched. Factory color codes change from car to car, but in the aftermarket (thank god) they keep them all the same. The red and yellow wires from the back of your head unit are always going to be your constant power wires, one for actually powering the radio, and the other for the clock. Your ground is black of course and the power switch wire will be thin blue with or without a stripe. These are the only wires you need to make your headunit function. Most people see the jumble of wires and get intimidated without realizing that 80% of them just go to the speakers.This should leave you with 8 wires (for the spearers) minus the ones you capped off. If your head unit turns on then you can attatch the speaker wires, agian using the 12 volts wiring color database. Hope this helps.