When you receive your new LED assembly, you may notice some labels on each of the wires. The labeling denotes where you will tap each of the wires to, in order to power up the LED assembly. Please follow the directions as labeled on the tags to ensure proper product usage.
This is a glossary of the locations where you will be tapping the wires and a general idea on where to tap your wires.
The battery positive terminal is usually located in the front of the vehicle, under the hood. Once you open the hood, you will see the vehicle's battery with a big red indicator that marks the positive terminal.
Some European cars are a little more complicated, so it may be a little more tricky to find the battery positive terminal because there are some instances of the battery located in the rear of the vehicle. However, there are still battery positive terminals in the engine bay area. The photo below is based on a BMW X5 showing a battery positive terminal location.
You can also refer to your owner's manual if you want to find the specific location of your vehicle's battery positive terminal.
The battery negative terminal is also located in the front of the vehicle, under the hood. The battery negative is denoted by an indicator that marks the negative terminal. The negative terminal is smaller in diameter than the positive terminal and marked with a (-).
Or, you can also connect the wire to the ground. A proper ground location will be one that is metal and clean of residue/paint.
The ACC 12V+ is located in the fuse box in the engine bay. To find a suitable ACC 12V+ location, you'll first need to open up your fuse box to test the relays. An ACC 12V+ location only gets power only when the car starts. If you can't find a unused relay socket, you'll need to pull off one relay in use. Try to pull out either the fan, horn, AC, and NOT the ECU, IGN etc.
Check out this video tutorial for a step-by-step walkthrough on how to find the ACC 12V+.
Some LED assemblies have an optional wire where you can tap to the headlight positive to turn off the DRL. You'll need to locate the headlight socket and access the back of the stock harness. There should be two wires (negative/positive). The negative wire is usually the black wire so you will tap the LED assembly's optional wire to the other wire, which is usually positive. Tap the optional wire to the positive headlight wire.
This is the same process as the one above, but with a different lighting function. Essentially, the wire tapping will be the same.
Some LED assemblies have an optional wire where you can tap to the headlight positive to turn off the DRL. You'll need to locate the headlight socket and access the back of the stock harness. There should be two wires (negative/positive). The negative wire is usually the black wire so you will tap the LED assembly's optional wire to the other wire, which is usually positive. Tap the optional wire to the positive headlight wire.
Tap the LED DRL wire to the turn signal positive. It's usually the most vivid wire color, as the least vivid wire color is probably the negative. However, you'll still need to test the wires in the stock harness to confirm the turn signal positive wire.
If there are three wires, tap the LED DRL wire to test to see if you have located the turn signal positive. You will basically be doing some trial and error to see which wire in the stock harness corresponds to turn signal positive. For example, in the photo below, there are three available wires that you will need to test to see which wire could be the turn signal positive. Since we know that the black wire is usually ground, you basically only have two more wires to test to see which one is the turn signal positive.
Optional functions are solely up to your discretion on whether or not you want to have that kind of function on your vehicle. If you choose not to tap the optional wire, it will not have any affect on the overall function of your LED assembly.