Installation Instructions for Bixenon Projector Solenoid Controller

What's Included

What You Need

Wiring Instructions

  1. After installing your projectors where you want them, decide on a location to mount the bixenon solenoid controllers. This location should be protected from the elements, since it is a bare circuit board. Inside a headlight housing is a good location. As the circuit board is very small, it could be fastened down using some caulking or RTV, or some epoxy. Be sure to be handle the boards fairly carefully as the surface-mount components on the bottoms are easily damaged.

  2. Bosch projector
  3. Your Bosch 3-wire projectors should come with a pigtail with a connector for the solenoid on one end, and three wires coming out of it: black, green, and red. After trimming the wires to the appropriate length and stripping about 1/4-inch of insulation from the ends, insert the ends into the 3-position connector on the bixenon solenoid controller. The connector is labeled "B", "R", and "G" for black, red, and green.

    bixenon controller installed
    Warning: Some models of this projector may have different wire colors. The photo above shows the projector I have, from the bottom, with the plastic cover over the circuit board removed. The photo below shows a slightly different model of this projector, with narrower circuit boards and different wire colors. As can be seen in the photo, the black wire remains the same, while the blue wire corresponds to the red wire, and the brown wire corresponds to the green wire. If your projectors have these different wire colors, be sure to take this into account.
    Bosch projector
    If you purchased pigtail harnesses from me, see the photo below for how to properly install them. On some earlier models of my harnesses, the connectors are not keyed, and can be inserted upside-down. Newer models have keys which prevent this.

  4. Bosch projector
  5. Attach +12V and ground wires to the remaining 2-position connector, which is labeled "+" and "-". These wires should provide 12V power and a ground connection when high beams are enabled. As every application is different, I unfortunately cannot provide detailed instructions here.


Now that you've connected your controllers to your projector solenoids, it's a good idea to test your new system to make sure the controllers are connected properly and the solenoids are operating correctly. To do this, turn on your high beams to activate the solenoids. The shutters should open quickly and forcefully, with a loud thump. After this, with the high beams remaining on, you should be able to close the shutters by hand, and they should either not reopen at all on their own, or only open very weakly. If you can't close a shutter by hand without it popping open with as much force as initially, then something's wrong, and the "pull" solenoid is being powered continuously, which is bad since it will eventually overheat.

Headlight Wiring

This diagram shows the electrical diagram for the Integra's headlights, in stock form. Other vehicles should be similar.

Integra Headlights
Integra Headlights

As you can see, this car has the headlights arranged in a positive-switched circuit, where the positive connections to the headlights are switched on and off, and the headlights' ground connections are always connected. This is probably the most common arrangement. Some cars have a negative-switched arrangement for some reason, so watch out for that on your car.

Like many cars, this car forgos using any relays on the headlights, and switches them on directly with the headlight switch. This is fine for regular halogen bulbs, but not for HID systems because of their very high current draw during warm-up. Also, you can see the multiple levels of fusing; some main fuses (100A, 50A) in the under-hood fuse box, and some smaller (10A) fuses for each individual bulb in the under-dash fuse box.

This next diagram shows how this system should be modified for HID bulbs and my bixenon solenoid controllers.

Integra Headlights Modified
Integra Headlights Modified for HID

In this circuit, relays have been added to switch power to the HID ballasts, along with an appropriate fuse and connection straight to the battery. In addition, the bixenon solenoid controllers have been added, and its labeled connections are shown. The B, R, and G connections are connected to the matching colored wires from the Bosch bixenon solenoid, the "-" connection is connected to a ground wire, and the "+" connection is connected to the high-beam positive wire. This way, the solenoid will be activated when the high beams are switched on.

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