Hi,
I want to double check my factory speaker wiring to see what is negative vs. positive. SOmeone said that if I got a cheap multimeter I could check this by attaching the speaker wires to the multimeter with the headunit on. They said if the reading would be negative or positive. My question is this, I have the Scosche multimeter, what do I put all the settings to? Please see the attached picture, that is the multimeter I have. Thanks and please let me know asap. Thanks, Landon.

 

Actually to see the what the Vrms coming out you would use the AC setting, BUT this will not tell you polarity. The signal coming out is a sine wave.

 

I like to have whatever that person was smoking hahha. What you can do is use the multimeter in the continuity setting( the one with the beep). This is only good if you know + or - at the HU. Is the HU after market or stock? Put the meteron cont., take one lead at the HU side then which ever wire at the speaker you touch that makes it beep is the same wire from the HU. Also you have to disconnect the speaker before you do this. Generally speaking, on the newer vehicles the wire with the yellow stripe is the (-).