How To: 9005 to 2-wire Bi-Xenon Solenoids

Here’s a quick writeup on how to make a “9005 to 2-wire solenoid” adapter, for connecting bi-xenon projector (e.g. AL aka “E46”) actuators to the high beam circuit inside the headlight housing of your P1 Volvo without permanent modifications (i.e. cutting wires). This assumes that you have the pigtail for the projector – if not, you’ll need to get that, too.

Wiring the "E46" AL projector bi-xenon solenoid using using a 9005 extension
Wiring the “E46” AL projector bi-xenon solenoid using using a 9005 extension
If you have 3 wires coming from your projector pigtail, and/or 3 wires running from the green circuit board to the coil, the connections are more complicated and you will need to get a 3-pin controller or use the BMW OE ballast.
Step 1: Cut off the loom to get at the wires

The 2-wire solenoid is connected in parallel with the high-beam bulb, so we need a connection to both wires, and the easiest way to do this is using a 9005 (aka HB3) extension. I used the iJDMToy adapter which has a ceramic output connector (probably intended for “hyper” watt cut-coil bulbs) and seems to be acceptable quality. The black loom was not split, so I had to cut it off.

Step 2: Cut extension, strip the wires to prepare for crimping.  Never use “t-taps” or “quick-taps”

Cut the extension, preferably as far away from the output (bulb side) as possible while leaving enough wire to work with on the input side. Strip off 1/4″ (6-7mm) of  insulation from the projector and the extension wires. If possible, try to find some high-quality butt-connectors (e.g. 3M) that have glue-lined heat-shrink (or use uninsulated ones and add your own shrink). The glue acts a stress relief which is important in automotive applications to stop vibration stress at the crimp point.

Step 3: Crimp on the output (female) ends. Try not to get too close to the middle until the other side is in.

I like to light crimp the easy side (close to the end of the barrel) before doing the tricker 2-wire connections. Once you’ve got the output side lightly crimped, twist the positive (pin 2, red or yellow wire) and the negative (pin 1, black, brown, or green wire) to the respective wire on the input side (male) connector and finish the crimp.

Step 4: Crimp the input side with the projector solenoid wires

Once everything is nice and tight (check by pulling hard on the wires) use a torch or heat gun to shrink and seal them.

Step 5: After shrinking, it’s done!

You can reuse the loom for a nicer look, not really necessary though..

With original loom reinstalled.

And that’s it!

Notes

Interestingly, I haven’t found many places you can buy these pre-made…

  1. AliExpress has them in bulk lots

 

The solenoid connector (female) is TE AMP 9-1718346-1 (replaces 968705-1), though 2-1718346-1 will work if you trim a small tab, and takes MQS pins, e.g. 20-18AWG tin is 965906-1, 23-20AWG tin is 962885-1