Advance LED Headlight Clearcoat Crazing/Flaking

Depending on what you pick up from the road, some materials can be quite abrasive or corrosive. Many car washes recycle the water, so these materials can accumulate in the wash-water. The best way to avoid such damage is to wash your own car.

I would turn the car around. I think it's ridiculous not to use a good extension cord. I know it's not recommended, but that's based on a hysterical approach to safety. The safety risks are practically zero if you use a good, heavy-duty outdoor cord.

 

Yep. Call Toyota's corporate office. That's ridiculous for that to happen in 2-1/2 years, especially in SoCal. Further, one can successfully argue that headlight effectiveness is reduced, producing a safety concern.

I had a similar issue with my 2004's taillights. For those who don't know about this, that first 2G year, the brake light LEDs were in a black plastic matrix that literally started melting (looking like a candle in a hot room). The "fins" of the matrix began to cover the LEDs. Dealer gave me a similar story to the OP's: it's cosmetic and not covered (under the extended warranty or otherwise). Once I pointed out the obvious safety issue of occluded brake lights, and she called corporate, her tune changed and they replaced them. The replacement lights have been fine for 6 years.

 

Mine has the receptacle at the rear of the vehicle. I thought only the prototype had it in front.

 

The clear coat on the headlight lens is a vital part of the light fixture.
Modern automotive headlights have Polycarbonate lenses. This type of resin is quite susceptible to damage from exposure to UV radiation and the clear coat is formulated to absorb the UV component of the sunlight before it can damage your headlight lenses. This coating is so vital that HID headlights have that coating on the INSIDE of their light fixtures as well as the outside, to protect the lenses from the UV rich part of the spectrum that Xenon lights emit.
Most cleaning solutions for transparencies (window cleaners like Windex) contain Alcohol or Ammonia which will destroy the UV Absorbing clear coat even if the cleaning solution is quickly rinsed off. If you need something stronger than clear water you can find a non-damaging cleaner in most any pilot shop at any airport. Most Aircraft Owners/pilots know better than to wash the expensive and easily damaged windshields of their aircraft with anything other than a cleaner approved for use on Aircraft Transparencies.
That said, the UV component of the sunlight where you are during any time except winter is about the same as what I have to deal with when I am in the Palm Desert area. That sunlight can kill any clear coat and Toyota uses clear coat on all of their paint codes including the solid non-metallic colors.
If you let the dealer renew the clear-coat on your headlight lenses make sure he knows it is a special UV Absorbing clear-coat he should be using and not just any clear-coat material. If he doesn't appear to know what you are talking about regarding a special UV Absorbing coating it is likely your headlights will not be correctly refinished with the correct materials.

 

Again, this is where "design flaw" lawsuits are born. It is totally foreseeable that solvent-laden liquids will contact headlights.

Maybe there's something to be said for tempered glass.

 

The Polycarb lenses are apparently the result of Federal Regulation (FMVSS 108) and not because it is the most durable material. High end European vehicles meeting ECE regulations like Mercedes or BMW and some VW group products like Bugatti and Lamborghini use Leaded Glass for their headlight lenses when the vehicle is made for any market except North America.
If the headlight lenses were made of the same acrylic resin as the parking lights or tail lights they would last the life of the vehicle, however the federal regulation is biased more towards how the material reacts to collision forces.

 

As I recall, some taillight lenses were made out of plexiglas in the 60s, and after a few years they basically rotted away.

 

Actually, not true. Glass lenses are perfectly acceptable, and in fact don't require the same types of testing that plastic lenses do. See 49 CFR § 571.108.

From what I can discern from this regulation, all plastic materials must undergo a two year test (in FL and AZ climate), and must not undergo visible changes within that period. For the OP, who has experienced significant hazing/discoloration/delamination in 2 1/2 years of actual use, this clearly suggests a problem.

 

My last three cars have all been parked outside full-time and each suffered the same headlight lens clear-coat breakdown between 4.5 & 5 years. So 2.5 years is too short a time under any circumstances. I do not use car washes and diligently maintain the cars by hand.

There are many do-it-yourself clear-coat kits available if you don't want to spend your time with Toyota.

Dupli-color Headlight Restoration Kit