My HID conversion experience

Here is my experience doing a HID conversion. I hope someone will find this useful.

From my initial research I though I will need a H7 HID kit (got the 4300K model) and a relay harness because the M5 uses the low bean as Daytime Running Lights (DRL). Here is the kit with the wiring harness.
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Since I will be using the relay harness to power the ballasts there is no need for the power connectors that is attached to the xenon lights.
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Power connectors removed.
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Here is a picture on how everything is to be connected.
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Now to the actual installation. I first removed the plastic covers that are over the driver side headlights, air box and battery. I than ran the relay harness to make sure that it will long enough to reach the 2 ballast. I would have preferred to mount the ballast with bolts but that was not possible and I did not want to drill holes. So I decided to use Velcro. Just make sure the area where the Velcro is to be mounted are clean. Here is a picture of the Velcro ready to be mounted.
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Once the 2 ballast are mounted its time to remove the original H7 bulbs. Here is the instruction on how to remove the factory bulbs. I would suggest practice reinstalling with the old H7 bulb before trying with the new xenon ones.
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I ran into a problem when installing the new H7 xenon bulbs, they require a spacer. I got my M5 used and don't know if the H7 bulbs on the car are original but they came with an adapter. I ended up cutting up the original H7 bulb adapters to make the spacers. Here are the pictures:

Original H7 adapter:
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Adapter saw in half to make the spacer:
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Spacer and new H7 xenon bulb:
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Once the xenon bulbs are installed is time to connect the power up. Here is how I hooked them up.

Factory H7 connection to relay harness. Note the wires and their color code.
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Battery connection and ground.
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Once everything was connected I tested the lights but ran into another problem with the DRL system. When the DRL is on the new xenon light would flicker.
To make a long story short this was solved by adding a 470uF 25V capacitor to terminals 85(+) and 86(-) at the relay socket to filter the DRL signal so the relay will not turn on and off to cause the lights to flicker. The capacitor is polarity sensitive, use a volt meter to make sure you have the right polarity. Here is the fix.
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After this modification, every works as they should. I just use tie wraps to secure the loose wiring and the 2 ballasts in case the adhesive on the Velcro fails.
Here are a couple of pictures of the completed installation.

Passenger side:
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Driver side:
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If you look on Ebay, there are lots of people that sell the H7 adapters for cheap. I've ordered a pair for my conversion for a grand total of $7. I'm a little disappointed that the kits doesnt come with them, but I'd reather spend the $7 than cut the factory adapters. If I dont lke the setup it's easy to switch back to factory if I have the original adapters!
 
so when you added the capacitor did the drl's still come on, just at full power? or were they just disabled. i've got an hid kit in the mail and this seems like the easiest solution i've come across. i don't care if they are off or on, just curious.
 
so when you added the capacitor did the drl's still come on, just at full power? or were they just disabled. i've got an hid kit in the mail and this seems like the easiest solution i've come across. i don't care if they are off or on, just curious.

The stock DRL system turns the original halogen lights on and off very quickly so the light is on but not at full intensity. This is fine for the halogen lights but the HID will not work because of the ballast, it needs a constantly on power source. The capacity on the relay's coil is acting as a low pass filter to keep the relay engaged all the time even though the DRL system is sending an on and off signal.

The HID will be on at full power all the time with using the relay kit and capacitor.
 
fantastic good to know, thats what i preferred. going to attempt the install this weekend and see how it goes.
 
I just finished my low beam HID install without any issues, but my fog lights was not successful. I broke the first bulb when attempting to install can someone point me in the right direction, do I need to modify my fog light housing?
 
I think there are reflectors inside near the tip of the fog lights, so you will have to make sure the new HID bulbs are not longer than the original halogen ones. Otherwise the new bulb will make contact with the reflector, or you will have to remove those small reflectors. Good luck.
 
question for davebert. did you (or anyone else) do anything to improve the seal around the bulb itself after the install? the rubber cover goes back on, but doesn't seal up tight to the HID bulb like with the stock h7 adapter, and it isnt held in place by the stock harnes either. so its not sealed tight. will this be an issue?

otherwise my install went off without any major issues. just the STUPID sping clip system holding the bulbs in. getting them done up (mainly the passenger side as i couldnt see in there at all) is a royal pain. so simple on paper, but in practice is another story. between that and getting all of the harness wires tucked out of the way was the "hardest" parts, the connections themselves were easy peezy.

for reference i used a ddmtuning 5000k 35w "raptor" kit with the extra harness. this kit did not come with bulb spacers either so i used the OP's method of cutting the stock H7 adapters. i used a dremel. i also used a 470uf 50v (as opposed to a 25v by the OP) capacitor and it works fine. couldn't easily get my hands on a 25v cap. makes no difference as it will never see anywhere near 50v or 25v. as for the harness, mine did not have the spade connectors on the actual harness, so i had to keep the power connectors attached to the bulbs unlike the OP and connect everything else up. its kind of redundant stuff but it all works in the end. the kit also did not come with brackets for the ballasts. i just used some 3m double sided trim tape and will see how it holds up.

the only thing i regret was not going with the 55w kit. the 35w is much brighter than stock, but more light could certainly be pushed out through the projectors.
 
I installed a DDM 55W 5k kit about 2 months ago and mine came with the adapters. I also have a DDM kit on my CX9 that has been there for two years now without an issue (knocking on wood). DDM is the best and most affordable kit IMHO.
 
I think there are reflectors inside near the tip of the fog lights, so you will have to make sure the new HID bulbs are not longer than the original halogen ones. Otherwise the new bulb will make contact with the reflector, or you will have to remove those small reflectors. Good luck.

How do I remove the reflectors?
 
Thanks for the detail write up. I follow it and was able to install this kit: Aukee 55W H7 HID Xenon. Good trick about the retainer. I use a 12 gauge electrical wire and wrap around the base instead. I will do your trick next week when I have sometime. Didn't want to break the old bulb because I didn't know if I should keep the set when I installed it. Interestingly, this kit also have the load register inline so DRL seems to work fine.
 
Just buy the retainers off Amazon or Ebay. I ordered mine from Amazon for $3. Shipped from China so it took weeks but it was worth it.

You can also ground the HID ballasts out and skip the capacitor step. It works just the same and there are bolts to ground to chassis on both sides near the headlight housing for the fenders.
 
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