Interpret the colorful lines of the Standard ISO wiring harness on a car stereo

The general type of car stereos are the most cost-efficient ones, but many people are worried about the connection problem as there are over 10 lines to deal with. This article will show you all the lines’ function and which to connect at the end of two sides.

ISO wiring harness 

If the ISO lines you got weren’t labeled with names, here are their roles:

A side is to connect with the car stereo, B side is to connect with the car.

The yellow line is the memory line to connect with the car power’s anode.

The red line is ACC to connect with car key’s ACC gear.

The black line is to connect with the power’s cathode.

The white line and half-white, half-black line are to connect with the anode and cathode of the left front stereos.

The gray line and dark gray line are to connect with the anode and cathode of the right front stereos.

The green line and dark green line are to connect with the anode and cathode of the left behind stereos.

The purple line and dark purple line are to connect with the anode and cathode of the right behind stereos.

If the ISO lines are labeled, here are their explanations:

REVERSE-IN: control your backup reversing camera, need to be connected with the anode of the reversing light.

ANT: to provide power for automatically elevating radio antenna or power on the signal amplifier of the radio.

AMP-CON: to control the car’s amplifier (if not connected correctly, no sounds will be released)

KEY 1: to control the steering wheel.

KEY 2: to control the steering wheel (most cars only need to connect with either one of these two lines)

ILLUMI: to connect the car head unit’s button light with the car’s instrument light.

BRAKE-IN: to control with the braking and warn you not to watch videos while driving. (most car stereos shut off this function before products leave the factory.)