Speedometer goes dark in tunnel/underpass -- normal? (solved)

Edit: Issue resolved (dimmer switch turned all the way down), review posted:

Review: 2012 Toyota Prius v Three - National Cars | Examiner.com




Hi all,

I review cars for Examiner.com, and I'm right now in a Prius v Three on loan from Toyota. I was wondering if anyone was familiar with this issue my test car has been having: when I pass through a tunnel or under a good-sized overpass, the speedometer and adjacent displays cut off until I'm back out.

I shot a quick video of one such instance, but the system won't let me post a link as a new member. Take out the spaces (but not the underscore) of youtu. be / r8k01wmxn_Y

Thanks!

Sounds like there is an optical sensor that upon detecting is is dark out, well like at night, and dims your interior displays accordingly. I imagine the headlights come on when things dim, part of the optical sensor system! There should be a mention of this in the owners manual. Dig it out and read it. It will help you understand how the car operates, thus helping you provide a more accurate and realistic review. Enjoy the car, be fair, and if you would, please post a copy of your review, or a link to the publication it will appear in!

With our (regular) 2010 Prius I've set the dash brightness wheel just below the detent that clicks it to maximum. It then behaves similar to what you describe, except that the dash doesn't "cut off", it just dims, when going through a tunnel or below an underpass. I believe that's normal behaviour.

Yes my 2012 mdl II will dim in the dark, but not fully out. Adjust the interior light dimmer to adjust to correct brightness. In brighter light it gets brighter so not to loose display by glare.

Thanks for the replies. The speedometer and other displays didn't just dim, they cut off altogether -- at least as far as I can tell. (If anyone with enough posts could post the active link or embed the video, that would be helpful.)

If it makes a difference, I was driving with the lights on (not auto).

look on the Lower Left hand side for the interior dimmer. Someone may have futzed with it so it dims way too low. Try setting it to as high of brightness and see if that helps.

It's normal to auto DIM when you have the lights on but what you're describing is fully turning off which maybe related to the manual dimmer control is set to the lowest setting. I will try this today.

BTW, is that GW Parkway you're driving on?

It would appear the dimmer wheel is completely turned down. When through the tunnel it will adjust brightness to the knob setting. You can turn the knob all the way down, which will do exactly as you show. But it will only turn completely off if your headlights are on.

So not under an overpass, wheel fully dimmed, it is on in the minimal brightness. You go under an overpass, wheel still fully dimmed, lights come on, display goes to set brightness of off.

Here is the video link: youtu.be/r8k01wmxn_Y

I'll play check the dimmer switch when I'm back in the car and report back. Thanks for everyone's help.

Right on the other side of the river -- Ohio Drive SW.

When dimmer controller is on the lowest settings, and when the headlights are on and it's daytime (sunny), driving through an underpass or a tunnel long enough for the light sensor to detect darkness, the lights in instrument cluster will dimm down in this case all the way off until the light sensor detects light again. I just tried it on my way home from work...

Adjusted the dimmer setting and all is well. Thanks again for everyone's help.

I just realized I hadn't come back and posted the link to the review. Use of social media fail!

Review: 2012 Toyota Prius v Three - National Cars | Examiner.com