What are these side (marker?) lights for?

TomCanada

Time for a (possibly) dumb question but I can't seem to find this answer so maybe I'm just having a moment - the 2021 Tab 400 has these little LED yellow and red marker lights at the corners, but I don't see them light up under any circumstances - what are they used for?

N7SHG_Ham

They should light up anytime the TV lights/trailer lights are on. Are your teialerbtail lights coming on as well as the three red lights above the stargazer window?

Denny16

The side and top rear lights are clearance lights to show a trailer is being towed, so other drivers can see the size of the trailer at night.  Most states require these lights on box cargo trailers and RV trailers.  They are basically a safety measure for night driving.  

Cheers

MuttonChops

TomCanada said:

. . . 2021 Tab 400 has these little LED yellow and red marker lights at the corners

. . . . I don't see them light up under any circumstances

While @Denny16 clearly defined the what/why of these lights.

I'm concerned that you have noted they Never Light.
If that is the case there is a wiring issue . . . Most likely with your TV 7-Pin connector, or fuses in your TV.

These marker lights should turn-on when ever your TV Headlights are On.

P.S.  They are Important Safety Features.  Many decades ago US DOT started requiring side
marker lights on standard passenger vehicles to reduce/stop nighttime T-Bone accidents as a vehicle perpendicular to your line of travel can be invisible at night even when that other vehicle has
it's headlights On.

Denny16

Connect the TaB at dusk, with the 7-pin cable to yiur TV, turn on the vehicle ignition (not necessary to start the engine or hitch the trailer up and get close enough to connect the cable) and turn on your vehicle’s lights.  Then walk around the trailer and check all the running lights and clearance lights.  Next, turn on your 4-way emergency flasher, and again check the tail/brake lights to see if the flash bright, then normal.   Check your turn signals, and if all is working, including the clearance lights, then Bob’s your uncle... 
cheers

tabiphile

TomCanada said:

Tab 400 has these little LED yellow and red marker lights at the corners, but I don't see them light up under any circumstances

To test the side markers use your VOM (amp setting) to jump the two adjacent (on either side of the locator) connectors on the T@B side plug and see if they come on. Or, use a 10 amp fuse or a wire jumper between them. They should light up w/o power from the TV. If they don't you'll need to troubleshoot on the T@B side.

TomCanada

Thanks all - I'll try turning the headlights on and report back!  I didn't think to do that - as my lights are headlights are set to automatic so only the daytime running lights illuminate in the day, while the full headlights come on when it's dark..

dlb

Turn your headlight switch from auto to on.  That may be your issue.

AirBoss

@dlb beat me to it. At least on .y TV, headlight switch must be in "On" position, not "Auto."

TomCanada

Yup it's on my to-do list.  Day job and rain got in the way of me trying it out today - hopefully tomorrow!

TomCanada

Sure enough - when I turn my headlights full-on, all the side and rear lights all turn on.  Thanks all!

AirBoss

Ain't life grand! 

ScottG

Yep. I love it when the solution to a problem is "Oh, it works exactly as it's supposed to!"  If only that happened more often...  :-)

Marceline

TomCanada said:

Sure enough - when I turn my headlights full-on, all the side and rear lights all turn on.  Thanks all!

Great. Those side markers are really important when you're cruising in the right hand lane at night and someone is merging onto the freeway. After a couple of close calls with my boat trailer I ended up putting reflectors across the entire right side of the frame. Maybe we need reflective "splats" for the side of the T@B.

N7SHG_Ham

As soon as I plug in my trailer, I do a walk around with lights on and make sure all are working, then turn signals, then brake lights. Obviously the OP must not of towed after dark since getting the Tab nor checked the lights. IMO automatic lights are attempting to solve a problem that really shouldn't exist and in the process have caused issues like reported here. I can operate a light switch and drive with my lights on 💯 of the time, way before DRL and automatic lights were the thing.

Sharon_is_SAM

I agree @N7SHG_Ham.  I don’t use the automatic selection as I always have my lights on while driving, towing or not.  It became a habit years ago from parking in a dark employee garage.  Once less thing to think about or remember.