Infotainment screen and dash dim with lights on

Although not all newer 5th gen 4Runners have this problem, I can personally vouch for the fact that the 2021 SR5 Premium has the issue (and fix) I'm about to describe.

Ever since I bought my T4R, I've been frustrated with the lack of brightness of both the infotainment screen and the dashboard during the day when I have my headlights on. Here in New York State, we have a law that basically states that any time your windshield wipers are on, your headlights need to be on.

I don't have any problem with the law, but my T4R had a weird quirk any time I turned the lights on during the day. Basically, as soon as I turned the lights on, my infotainment screen and main dash went into "night mode" which makes then significantly dimmer. The big problem was the backup camera which pretty much became useless when this happened. Sure, turning off the lights brought it back to full brightness, but it was a bit of a pain. No matter what I did in my Setup screens, the problem persisted.

So why do these screens go dark on my T4R and not on most cars? Because most cars have a light sensor on top of the dash that tells the vehicle if it's light or dark out. My T4R did not come with one and thus as soon as one turns the lights on, the vehicle assumes it's dark and dims everything. All I had was a plastic dummy plug clipped onto the wiring harness that does exist. Oh, and this dummy plug looks just like the sensor - until you pull it out.

After some searching around the internet, I found several folks suggesting that the following Toyota Part Number is a plug and play fix, so I ordered this:

$17 Auto Light Control Sensor 89121-50020 for Lexus Toyota 4Runner Avalon Camry Highlander Land Cruiser RAV4 Sequoia Sienna Tundra Venza

Amazon.com: Auto Light Control Sensor 89121-50020 for Lexus Toyota 4Runner Avalon Camry Highlander Land Cruiser RAV4 Sequoia Sienna Tundra Venza : Automotive

After gently prying my dummy plug out, I quickly discovered that the above part is not correct in that it has a completely different plug configuration. Here's the above part number (left) and the dummy plug (right):



Time for some more digging.

What I eventually found was that there is a different part number that actually works:

2014-2022 Toyota Ambient Light Sensor 89121-0E060 | Grieco Toyota Parts

Yes, there is a significant price difference, but this part works and the one everybody else says to buy did not work for me. This one is definitely plug and play and my original problem is totally gone.

Hope this helps some of you out!

 

Is this problem different from the setting of the dimmer in the setup?

 

Yes

 

Thanks

 

Great info