My 2001 RX300 AWD has about 10K miles.

Last week I happened to notice that the high beam lamps/bulbs seemed to be cloudy, a smoky grey film on the interior of the glass. So I bought replacement bulbs yesterday.

On removing the OEM bulbs I confirmed the interior of the bulb's glass enclosure is heavily covered with what appears to be soot, most likely from the bulbs operation at the low DRL voltage. In addition, there was a definite "bubble" in the glass immediately above the filament, likely due to heat buildup that the glass was not designed to withstand.

I went ahead and replaced the bulbs but at the same time I disconnected the DRL resistor under the battery on the chance that was the source of the "sooting" problem.

 

I noticed the same on my 2000 RX. I took a close look at the high-beam bulbs and noticed some sort of brown buildup on the tip of each bulb. I was surprised to see it there. I just forgot about it and it never really bothered me.

It's just interesting to hear you having a similar occurance. You're not alone!

- Nick

 

I found the same problem on my RX last summer when I replaced them with higher output 'blue' bulbs. What may have happened is that in the process if putting them in place at the plant they were handled with bare hands or some vapor from assembly got cooked when they were first used. My new bulbs have not done this yet and it has been months.

 

maybe this is a problem with the drls because after reading this post i looked at my bulbs and found the same thing, should i replace them?-paul

 

I have the HID lights and wanted the Drive/Highbeams to be blue also, so I put in some 100watt blue PIAA type bulbs in about 6 months ago and the have been great.