Audio Systems: wiring, 4 ohms, memory backup

Question
My car was broken into and the stereo was stolen. We went out to buy a new one, only to find that when we went to install it, the car had been totally rewired from the last stereo that was installed. How do I install a stereo when the car has been re-wired.not alot of the colors match and my husband and I are confused.

Answer
Hi Christina,

This is a process you will need a multimeter for.

With the keys out of the ignition, Test for +12V on all the wires. One should have +12V, (this will be Batt or memory backup). Now turn ignition ON & test all remaining wires. One of these will now also have +12V (this will be ACC) Turn headlights ON & test remaining wires for voltage (this will be ILLUM) - With remaining wires check for continuity. There will be 2 wires for each speaker and when you have a correct pair, you will have a reading of 3 - 4 Ohms. Once established tape each pair together so you they don't get mixed up with other pairs or other wires. Then check continuity with the frame of the car - The wire that has continuity (approx 0 ohms) will be GND.

Test each pair of speaker wires with a 1.5V battery to hear a sound from a speaker. Take note of which speaker is making sound.

Now connect the stereo with the wires you have identified.

Let me know how this goes.

Regards Baily :)