This is why rear windows are shattering spontaneously on newer Acura RDXs

Acura is aware that rear windshield glass on RDXs are breaking and will inspect and replace glass on affected models.

Researching rear windshield glass shattering on a completely different make and model car and I came across the fact that newer Acura RDXs (around 2019+) owners suffer from their rear windows spontaneously shattering for no apparent reason.

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This is the thread on AcuraZine that brought this to my attention.

It happened when RDX owners after they parked for a while, overnight waking up to the sound of glass shattering, or worse, while driving.

Head on over to the National Highway Transportation Association’s website, navigate to your year RDX (like this one for MY 2020) over to the complaints section and invariably you’ll come across dozens of owners complaining about shattered rear windshields.

“I went out, got in the vehicle and before starting, I heard a crinkling/rustling noise,” says one RDX owner. “It sounded as if something was in the rear of the vehicle. I got out of the vehicle and walked to the back and the entire rear window glass was shattered. There was no impact, no foreign object hit it, etc. It simply shattered while sitting in the driveway, with the vehicle off, when I closed the door. “

Complaints got so bad that Acura finally had to address, investigate the issue, and come up with some kind of response.

Acura did not recall affected RDX but instead issued a Technical Service Bulletin in June and updated it in October including additional affected RDXs.

I’m posting TSB 22-014 below.

All 2019 Acura RDXs and certain 2020 Acura RDXs within a certain VIN number range are affected.

According to the TSB the possible cause is an, “incorrect specification for the rear defroster grid.”

In other words, an improperly installed rear defroster grid (that grid of wires on the back of your windshield that heats the glass) or a defective rear defroster is the source of the issue.

This sort of issue doesn’t happen to just Acuras, over the years it’s been an (and continues to be) issue for all sorts of makes and models.

This thread from Jeep Wrangler owners suffering something similar further sheds light on what possibly’s happening with these RDXs.

From what I understand, a defective defroster grid, whether you turn it on or off, can cause an overheating condition or a hot spot on your rear windshield.

Rear window defrosters only ever get as hot as 85 degrees Fahrenheit so, a malfunctioning defroster, sending rear glass temperatures beyond that set point, can surely cause what’s called a thermal fracturing event.

Per the TSB, it looks like Acura will replace the affected rear glass free of charge.

As of this blog post a lot of car parts are still recovering from supply chain issues so you might have to wait a bit for new, unaffected glass to come in.

If you’re an RDX owner and this happens to you, I’d call your local dealership ASAP, get it fixed, and, when you have time, log the event in the NHTSA’s database under the appropriate year (click here to Report a Safety Problem to the NHTSA.)