Looks like you just can't go by what some of these sellers tell you. The ballast that I bought was claimed to be for the left side so I associated the W3TXXXXX with the left side. NOT SO. With some difficulty, I was able to view the OEM ballast on my car on the left side and it is X6TXXXXX. Then I looked at the ballast that I have on the bench and did a DUHHHHH...... it has the W3TXXXXX! There is no difference left to right as far as the number is concerned. For some reason, Mitsubishi must have had different ballast runs with different numbers on them but they are the same part functionally. Talk about chasing my tail.....Well, now I know. Much todo about nothing it seems. (I have to stop talking to myself..... )
John

 

Unfortunately I haven’t found a solution nor have I found out what the actual problem is. I’m still looking for an auto electrician that won’t charge me a huge cost just for a diagnosis on top of actually fixing it.

but I ordered the bulb and ballast (came
as a pair) from this website because it comes with an optional lifetime guarantee for a decent up charge.

https://www.hidsrus.com/

 

My problem was a bad ballast and finding one that would correctly mount to the brand new AP1 housings that I bought was more of the problem. I finally obtained a good used one from a garage in the UK by stressing that he PLEASE test the ballast before sending it out to me. He said that he would and when received, I also tested it and it was good to go. I got some new Morimoto bulbs for each side (D2S), removed the inner fenders on both sides and changed them out. It was not so bad of a job.
Does the replacement ballast that you bought have the same bolt pattern and mounting arrangement as the OEM? Keeping the inside of the headlight housing sealed from moisture is an important thing. Kudos to you if you have found a compatible ballast that's new. Honda's, ofcourse, is prohibitively EXPENSIVE at $800 ea via dealer.
So that was my experience anyway. Hope yours works out ok for you.
John

 

no they were aftermarket ones so I had to do some MacGiver-ing. I had to buy a T bracket from Home Depot and drill the ballast onto the T bracket and then screw the T bracket onto the headlight unit where the ballast goes. These ballast were a little different and plug and play so I bought some rubber caps also from Home Depot and cut a hole big enough for the wires and applied some weatherstripping to seal it. If I ever remove my front bumper I can take some pictures but it won’t be for awhile.

For context, my passenger side went out when I had all OEM and then I had a minor collision on my passenger side fender and so I used my insurance and took it to a collision center where they repaired/replaced and painted my fender. While they were doing that I had them replace my headlight units with SPEC D Ones and with the bulb and ballast. I thought that a replacement would fix the issue but when I got
my car back they told me that it still wasn’t working. They checked the voltage, the fuse (and replaced it just in case), the switch, everything and couldn’t find the issue and suggested I take it to an electrician. They said it might be a wiring issue.

 

The OEM ballast has a single braided ground wire that goes from the metal ballast housing to a standard 1/4" spade plug on the housing. The spade terminal goes directly to the negative side of the bulb socket to complete the circuit. Be sure that your new Spec D housing has some way to ground the metal negative side of the circuit otherwise the light in not going to light. Just a thought. Many electrical problems wind up being caused by poor or non-existant grounding.

 

the drivers side works fine after all the install of the aftermarket parts so it’s weird that the passenger side doesn’t mirror the same results