For sale here is a controller circuit for Bosch bixenon (or bi-xenon) projectors which use 3-wire solenoid connections which are commonly found in the BMW E46, M3, and Mercedes CLK. We also sell 3-wire pigtail harnesses for connecting these controllers to the Bosch projectors.
Why They're Needed
Bosch bixenon projectors are commonly found in many European cars, especially the BMW E46, and have become very popular for retrofitting into different cars' headlights because of their low price, good reputation for performance in a small package, and ease of use in retrofitting. These projectors are fairly easy to find on Ebay for $75-150 per set.
These projectors use solenoids to change the position of a metal shield, so that in one position it acts as a cutoff to prevent light from blinding oncoming drivers, and in the other position this restriction is removed for full brightness. The problem is that there are actually two solenoids in this package, a strong one for pulling and a weak one for holding, and consequently there is a 3-wire connector on the projector. For proper operation, the pull coil is supposed to be activated for about 1/5 of a second, and then turned off while the hold coil is still powered as long as high beams are desired. The hold coil alone is not strong enough to move the shield, only to hold it in the high-beam position. While it is possible to just use the pull coil all the time, powering the pull coil for long periods of time is not a good idea because it consumes a lot of power, and consequently generates a lot of heat. The solenoid is not designed to get that hot, so this would certainly reduce its lifespan a great deal, and it would probably burn out quickly.
Normally, in the E46 car, the solenoids are triggered by a special circuit that is located in the ballasts which came with that car. If you're using these E46 bixenon ballasts, then you don't need our circuits at all (go here to see how to use this functionality), but most people buy these components separately on Ebay and end up using different ballasts which don't have this extra circuit built-in. So I designed these circuits to handle this. See these diagrams to see how the OEM Bosch system worked, and how our components replace its functionality.
We have seen another circuit on the internet for controlling these solenoids, however this circuit uses a relay and a capacitor and resistor to achieve the proper delay. While this probably works (we have not tried it), we believe our circuit to be better because it uses a MOSFET transistor and therefore has no moving parts unlike a relay-based circuit, making mine extremely reliable. It is also much smaller, and could be easily hidden inside a headlight housing or other enclosure.
This device is shipped as a bare circuit board with two connectors: one to connect to the solenoid and one to connect to the high-beam circuit. You may mount these boards anywhere you choose, though it is advisable to mount them inside the headlight enclosures where they will be protected from the elements. Each unit is fully tested. Normal orders will be for two units, though you may order a single unit if you wish. For the sake of reliability and easier wiring, we recommend buying two, one for each headlight.
The only catch for buyers is that they must handle the installation themselves (or hire someone such as a car-audio installer who knows how to deal with car wiring). But if you're retrofitting projectors into your headlight housings yourself, you can probably handle this as well. These circuits are easily wired with only a screwdriver, as the connectors have a cavity where you insert the stripped wire end, and then turn a screw to clamp it in place.
This controller circuit is designed for the Bosch bixenon projector solenoids normally found in the BMW E46 and other vehicles. It will interface to any vehicle which can activate high beams with a simple +12V connection.
To make sure your projectors need this device, check the photos below. The left picture shows the correct E46 solenoid circuit board, which needs a circuit such as mine to control the solenoids. This variant usually has a solenoid marked "Binder" or "Kendrion" in black. The right picture shows a different variant of the E46 projectors, which only has two wires and does not need a controlling circuit. It usually has a solenoid marked "Kendrion" in red. Notice that the middle pin does not go anywhere on the circuit board on this one.
|Correct Solenoid (needs controllers)||Incorrect Solenoid (does NOT need controllers)|
The price for this bixenon solenoid controller is $18 for a pair, or $9 for a single unit, plus any applicable shipping charges. When you purchase using the Paypal checkout, it will calculate your shipping and should give you multiple options for shipping.
Additionally, if you need the 3-wire pigtail harnesses to connect the controllers to your projectors, we are offering these for an additional $10 per pair, or $5 for a single harness. You can purchase these by selecting the appropriate button below. Please see the Installation Instructions page to see how to properly install these.
Interested? You can order one or a pair quickly and easily by clicking on one of the buttons below. Feel free to add more products to your cart before checking out, such as the Time-Delay Relay, and save with combined shipping. If you would like to pay by money order, or have some other special needs, just email us and let us know how we can help you.