Please help troubleshoot HID headlights

Brief background: 2009 Toyota Tacoma. Replaced original headlights with Notto HID headlight kit. First bulbs used were 10k...too blue...my mistake thinking the higher the number the brighter it would be. (I'm visually impaired) Replaced the 10k bulbs with SDX 43k HID bulbs...better, brighter, and not blue. Everything worked well.

Recently both headlights would turn on intermittently. Sometimes both headlights would not turn on for a few minutes, but then would turn on. Then it took longer and longer to turn on, but at least it would eventually turn on. It took a few months...now, it just won't turn on anymore.

This morning, I replaced the passenger headlight bulb (per advice of threads here)...nothing. It did not turn on. I am suspecting it is not the headlight bulbs. What could it be?

I know it can't be the fuses.
I am thinking it can't be the ballast...both couldn't be bad at the same time.

What could it be? What part controls both headlights?
Confession: I am old. It was actually my nephew who helped me install the HID kit over 5 years ago. It worked well until recently. Please help. Thank you.

 

Do both of the headlights come on at the same time? If so then you can rule out ballasts.

You may want to get a voltage meter and check that your are getting 12v at the relevant connections, and have someone work the relevant headlight switches while doing so.

Also might be worth your time to temporarily disconnect HID system and plug back in your factory bulbs to see what happens.

 

Do you have a full projector retrofit?

If not, rather than trying to fix that setup I would suggest replacing it with this one:
https://www.tacomaworld.com/threads/the-ultimate-headlight-upgrade-not-led-or-hid.398066/

 

Yeah! Definitely don't stick HIDs in a reflector housing. Or you're just a damn Douchebag.

 

May have a wiring or ballast issue. You can get more and better light output by simply changing to better lamps using stock wiring and road legal DOT certified optically engineered OEM housing. Here's how..

https://www.tacomaworld.com/threads/brighter-head-lights.493397/#post-15265236

 

Once again, thank you to all.

After checking the wiring and voltage...we still couldn't determine what's causing the headlight not to turn on. Per your advice, we decided to remove the HID kit and re-install the factory bulbs.

Both headlights work again. Thank you.