JasonARGY

Ok, back with an update. It was the fusebox/junction box. It seemed unlikely that it was it since both headlights started flashing at the same time and then subsequently permanently died at the same time.

I took a risk and ordered a brand new, OEM part from a seller in Japan for $170. Used they seem to sell for $150 to $200 and about $280 brand new from the dealer so I was skeptical but I went for it. (Part Number: 82720-50081). The part I received is either an incredibly well-done fake or actually OEM. I'm convinced it's real.

Seems like this may indeed be a pretty common issue but if my new junction box can last another 13 years, I'm okay with that. Thank you all for all the support and help over the last month basically trying to get this sorted out.

JasonARGY

Does anyone know if a repair like this could cause the alternator to go out? After 3 days, the car suddenly was struggling to crank over and while at idle, I'm seeing about 10.4V. With car off i see about 12.2V.

Luckily, I was at the store, it cranked over really slowly but started, then after about 30 sec the AC turned off and I got a reduced power warning, but then it went away so I quickly drove home and parked it. I'm assuming it's the alternator as I smelled some sort of burned smell from under the hood and with the car running, I would expect at least 13.5V. I'm just curious if this is pure coincidence or there is something that possibly cooked the alternator.

swfla

iTrader: (1)

Stuff breaks. It's hard to guess if there's a common source. Having a trained tech hook the car to TechStream is your best bet if you need an answer and don't want to just keep throwing parts at it.

2007ls460l

You should consider checking the battery terminal connections. They may be loose, and I'm sure you disconnected / reconnected them when changing the relay box. Glad you were able to get the headlights working!

kdjae

Update from South Korea

I experienced the same problem, so I changed the bulbs but it was in vain.
Then, I went to the local Lexus service center in Seoul, and then the technicians found out that the under cover of the 'Junction box' was broken.
They recommemded me to change the junction box. I remember that the prices of the parts was more than US 300.
When they changed the whole Junction box, the problem was gone.
They were right. There might have been water penetration or someting unknown through the broken cover and it caused the malfuntion.
Anyway, I don't have futher headlight problem after the repair for more than a month.
Hope my experience is helpful.

Jimmy84

Many thanks! It was very helpful for same issue!

Also, I have opened an old unit. This is not just junction box, it has SMD board with relays and electronic switches. Not sure if repairable, due to protective silicon layer.