Tracksyd,
Did you have to use a separate wiring harness with the DDM HID kit? Also, did you have to remove the DRL fuse to get the HIDs to work with out any issues? The reason I am asking is that I have installed 2 AC Digital HID kits (HIDLook, XenonSupply) and on both kits, either one side works and the other doesn't, or they both don't work, or the both do work; very intermittent. I did reverse polarity and even tried switching ballast from one side to the other but I would never get both HIDs to consistently turn on. I'm thinking its the ballast but they're both brand new kits. I ordered a set of the DDM slim HID kit in hopes that I have better luck. Thanks.
No, I didnt use a separate relay/wiring harness. I just used the wires that came with the ballasts to plug into the stock harness. I didnt need to do anything else funky other than mounting the ballast and plugging in the wires.
With that said, my friend bought a DDM slim ballast kit at the same time as I did, but for his Prius. He had the same issues you are describing. We swapped out bulbs and ballasts with ones that worked on my Sienna, but he still had intermittent firing issues. He even installed the relay harness, but that didnt seem to make a difference.
This was about 18 months ago. I actually asked him last week if he still had any issues and he said that a few months after installing them, the intermittent firing "went away" and that now his HIDs fire up fairly consistently. So much so that he doesnt even think about it anymore.
Another thing I will throw in is that when I was researching the DDM kits, I found a post on a BMW forum or something where the DDM guy was talking about his kits. He said the "fat ballast" (the non-digital ones) were by far the most popular and trouble-free ballasts he sells. IIRC, he even claimed they may be the most reliable on the market.
I've recently been looking into HID kits for another car and the retrofitsource.com came up a lot as a reliable source. When I looked at their kits, I saw it used "fat ballasts" (appear to be non-digital). So with that said, if you just cant get digital slim ballasts to work for you and you can get over the "fat vs slim ballast" thing, then you may just want to go with the fat ballasts. On my Sienna, I'm actually using the fat ballasts in the fog lights and the slims for the headlights. In the 18 months I've had them, neither of them have given me any issues (although when I first installed the slims, I did have one ballast swapped out).
Lots of people will say to run the harness. But from what I've seen, I dont think that is necessary. Yes, it may be better for your stock wiring. Yes, it may help with intermittent firing (but I think that has more to do with loose tolerances between various ballasts). But in my Sienna, they've been pretty reliable without it.
I was going to go with another brand of HID kit for my other car. But I've since decided to just get another set of the DDM slims, but I'll get it with the harness. The cost for the kit + harness is still less than most of the "so-called reliable brands". I will also say though that I work fairly close to DDM's office in Huntington Beach, CA. So its much easier for me to take advantage of their lifetime warranty on their bulbs and ballasts.