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.
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.
Power connectors removed.
Here is a picture on how everything is to be connected.
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.
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.
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:
Adapter saw in half to make the spacer:
Spacer and new H7 xenon bulb:
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.
Battery connection and ground.
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.
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:
Driver side:
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.
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.
Power connectors removed.
Here is a picture on how everything is to be connected.
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.
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.
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:
Adapter saw in half to make the spacer:
Spacer and new H7 xenon bulb:
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.
Battery connection and ground.
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.
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:
Driver side:
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