SangerZ28

Hi everyone, this is my first post but I've been following this forum quite a bit! So my wife has a 2015 ML350 with the standard lighting package. We agreed that since the first night we took the car home, the headlight performance on the halogen headlamps is horrible. I ordered a HID kit from DDM and tried to hook it up today. I installed just the right side first and wanted to test. I fired up the car and had the lights on. The driver side halogen comes on, but the HID doesn't. I flipped the power wires around in case I had the wrong polarity. Fired up the car again and same results. I took the entire assembly and connected it straight to the battery just to test that it all works. Sure enough, the light comes on nice and bright. So I know the issue isn't the bulb or ballast. Does it require that I have both HID's installed first? I didn't hook up the driver side yet cause I need to move the car out of the garage and it was raining today. The other thing I was thinking was it may need a relay harness, but I didn't find any HID threads on here with anyone stating they needed a harness to power the bulbs. I even connected my volt meter to the power output on the connector and get around 13 volts. I put the factory bulb back in and tested, and it lights right up. Any help or tips would be appreciated!

AZN Optics

You need canbus enabled HID kit, not just any generic kit to play nice with the SAM.

peter2772000

In other words, you need to fool the car into thinking that the factory bulb is still in there. One way, I would think, is to feed the HID's directly from the battery thru a relay actuated from the OEM power source feeding your halogens. On the coil of that relay you'd need a resistor with the same resistance as the factory bulb so that the car believes everything's normal. You'd have to make sure the resistor would be able to handle the wattage though. I'm guessing 50-60 watts?

I'm pretty sure the above would work. Anyone?

SangerZ28

I did ensure the kit supported CANBUS as I knew this would be required for the ML350. Here is a link the kit that I got if it's OK to share on the forums. It's the H7 model with 4500K bulb @ 35W.

http://www.ddmtuning.com/Products/DDMPlusCanbusHIDKit

SangerZ28

I'm starting to think I may need a relay as well. I'll wait to see what anyone else may suggest first before ordering.

AZN Optics

DDM kits are hit or miss with quality control. You might just have bad ballast and should hit them up for warranty replacement. One of the reasons we decided not to distribute their hid line in favor or more reliable Morimoto units.

peter2772000

He already tried powering everything up directly to 12v and it all works, I'm guessing you didn't see that in the OP's post.

Sanger, AZN is right though, and not just about DDM. There are very many outfits out there who sell sub-par stuff. So you have two choices; Send the kit back, get reimbursed and buy a Morimoto kit, or do the relay thing. With the relay option, you'd have to track down the proper resistors, relay etc. And in the end, you may very well end up yanking it all out after a year due to reliability issues.

Been there, done that!