Why won't my reading lamps come on in my 2009 Tahoe?

Question edited for clarity and typos.
Question moved to model category.

Others report the same issue.

https://www.google.com/search?q=2009+Tahoe.+The+rear+lift+gate+open+on+its+own

Chevrolet Tahoe Powertrain Control Module Replacement Cost

https://repairpal.com > estimator > powertrain-control-...
The average cost for a Chevrolet Tahoe powertrain control module replacement is between $448 and $514. Labor costs are estimated between $96 and $121 while ..

The acutal brake lights are on constantly or the bake warning lamp in instrument panel?

Double check the ABS fuse and relays are in and proper. A malfunction in ABS will disable stabilitrac,

Are they burnt out

Check the owners manuals for reset

its all in the service manual seen below links.

what if there is no flasher module at all? (dedicated in olden days)
and THERE IS NOT ONE.
and is the BCM job to do that. as many are now , all? newer cars.
bingo this car BCM does it all.
whats failing?
all 4 corners dead.?? and mirrors and cluster blinker active lamp?
too fast or too slow??
hazard switch fails too.?
nobody like to hunt things that do no exist. and does not.

so post a problem and we go to the cause, and avoid useless hunts/
answer 1 scan the PCM and check fuses first
most cars 2009 flat tell you why it fails , why not do that first?
chebby tahoe, 09
ok I read your SM and there is no flasher like seen for 100 years
here, its GONE they blinker is a software loop inside the BCM
(body brain box) bbb
there are only 2 fuses but those bad cause right of left to fail
not both or all of them ever. 6+ (mirrors too)
the BCM has 4 outputs to blink all lamps so its NOT outputs bad

1. just , fuses blown (x2)
2. or BCM needs a reset, or battery is weak main (does car drive?)
3. or BCM bad.

the answer is learn to scan the car first and save time.

https://eautorepair.net/Marketing/Default.asp

Sounds like you have a tire pressure sensor in a tire going bad. Have it replaced and it should work

The air bag warning lamp should work, so that isn't a fault in itself.I'm therefore assuming that the warning indicator lamp is staying on after startup, which would require that you plug in a diagnostic computer and read any fault codes.

spanish on a USA english only forum.
ok,,,
red light illuminates on the board with the symbol (!)
why not post a photo of that lamp.
if car is no in USA< the lamps are all different, so where are you?
in SPAIN?
the glove box, has the operators guide, remove it and read the page on warning lamps, its all there to read, just read it.
if lost?, buy one, and not get stranded for silly lamps... ignored.

in CANADA< the (!) lamp is brakes bad
but im just guessing your unstated country.
99.9% of all post fail this way, no country stated, and is just a silly waste of time...
btw cars work different in different countries, by law......etc.

I would recommend not doing it...