No power to left rear turn/ brake light

automatic transmission or manual stick, the brake/clutch switch operations are NOT THE SAME on both car options.
no country told, lighting (for sure external) are not the same all over earth, sorry I do not make laws (like DOT USA?) or anywhere.
this forum is www, a world wide web forum. so where are you ,a country.?
and you work with no voltmeter or service manual schematic.
and no scan tool? wow endless guessing done. throwing parts wild.
its is modern car, 2009 totally unlike a 1990 or 1980 or older car.
for sure.
there is never a need to replace all fuses ever, testing is super easy even if they all look good. (did they?). (look test, ohms or volts tests)

that melting thing means a lamp shorted. (they can)
I see reverse lamps failing and parking lamps
the transmission PRNDL SWITCH MUST WORK IN "R" OR THE LAMPS WILL BE DEAD REVERSE. BOTH WERE SO.....
I GUESS INDICATOR MEANS turns signals failed( blinkers)
the car has 4 corners, why not tell what all 4 do when Turns or parks fail.?>??? what they all do outside matters most. (electrics)

the huge problem here is not scanning the OBD2 port with a real scan tool. I bet it tells you why it fails I sure do but you failed to do that.

does this car have the parking AID option?
does this car have optioin
Daytime Running Lamps, a.k.a DRL?>? also wiring for TT is unique so states the SM (service manual)
i can't see you work on any car so now comes right parts questioln
using only these parts.,
Rear Turn Signal Bulb

1. Left/right Rear Turn Signal Bulb M6
2. Right Rear Turn Signal Bulb M8
3. 12 V, 18 W
4. W16W

the German manual calls park lamps TAIL even when front and side park lamps are park lamps. same source.
It does call TURNS turns, so we can find the correct schematics,
searching the online service manual for you.
most modern cars, use BCM to run all that. I call it the body brain
each maker uses there names and Germans use CODES
LIke J123. to name a model. (that must be decoded first to work the problem, yes a pain on all germane cars)
deep in the manual i found the secret german body brain
J519 - Vehicle Electrical System Control Module
this module runs the whole rear (it has DRIVERS)
Drives means electronic high power regulator drivers to lamps.
that if it sees a short , it simply goes OFFLINE until cures.
then magically goes back on one,

J519 - Vehicle Electrical System Control Module
M6 - Left Rear Turn Signal Bulb
M8 - Right Rear Turn Signal Bulb
M9 - Left Brake Lamp Bulb
M10 - Right Brake Lamp Bulb
M16 - Left Back-Up Lamp Bulb
M17 - Right Back-Up Lamp Bulb
M37 - Left Rear Side Marker Lamp Bulb
M38 - Right Rear Side Marker Lamp Bulb
T2g - 2-Pin Connector, In the Luggage Compartment, Right, Black
T6k - 6-Pin Connector
T6l - 6-Pin Connector, Black
T12c - 12-Pin Connector, Black
T12d - 12-Pin Connector, Brown
X3 - Rear Fog Lamp
395 - Ground Connection 30 (in Main Wiring Harness)
662 - Ground Connection in Left Rear Side Panel
676 - Ground Connection 2 in Luggage Compartment, Left
------------------------

J519 is here
Behind driver's left stowage compartment, beside steering column -2

Fuse 7 (On Fuse Panel C)? blown fuse?
this car uses CAN BUS.
many of the switches wire directly to the J519 Body brain
but not all.
lets look at that now, (my book is USA only SM)
the steering switchs for park, turn and heads.
are all sent to the cluster brain directly,
then the cluster brain via the CAN_BUS network sends data commands to the J519 (body brain)
then if this fails the scan tool told you it did but you never scanned the OBD2 port. while failing
others found water leaks to dash module (windshield cracks or glued in wrong and leaks)
some Audi versions 2009 have top of brake pedal brake switch that must work, and is direct drive signal to J519
TURNS are not switch actual direct drive to the J519. no.


example 1
U1113 Audi Code
lacking scan tools you will never fix this by guessing. sorry
CAN Bus wiring intermittently open, shorted to power or ground
U0001
U0155<< lost comms to IP cluster.
and more lots and lots more possible
we check all fuses in all fuses boxs A ,B,C etc.
then scan the OBD2 port. for errors. for sure comm errors'

see this fuse box?

Main Fuse Box in Right Rear of Luggage Compartment on Battery see? drivers (electronic) to each lamp. proof (no fuses to lamps)
so if one lamp shorts. the other do not die. by design
and J519 must get the commands to turn them on first.

Check that it's earthed properly. Might be a little corrosion on the contacts.

If the other brake and turn lights are working the brake light and flasher units are ok . With a test light check at the bulb holder terminal and bulb holder body, test light should glow ,if not check from terminal to a metal part of panel away from the light body . If test light now glows the brake light body has a bad earth if the test still not glowing the power cable to the light is broken.

Tail Lights
The procedure for removing and installing turn signal light bulbs is the same as that for brake light and taillight bulbs. Only the procedure for brake light and taillight bulbs is described here.

1. Before servicing the vehicle, refer to the Precautions Section.
   
2. Disconnect the battery.
   
3. Switch off all electrical connectors.
   
4. Turn off ignition.
   
5. Remove the rear light, as follows:
   
6. Remove the rear striker mount cover.
   
7. Reach behind the respective quarter panel trim and unscrew the knurled nut. Make sure the washer and spacer do not fall down.
   

Taillight housing

Remove the rear light and disconnect the electrical connector.

Turn the bulb holder in the direction shown and remove from the housing

Turn the bulb holder in the direction shown

1. Remove the bulb from holder.
   

To install:

1. Install the bulb in the reverse order of removal. When installing, make sure bulb holder engages in housing by turning in opposite direction.
   
2. Install the rear light, as follows:
   
3. Connect the electrical connector.
   
4. Insert the rear light housing into the body opening.
   
5. Insert the retaining bolt into the body opening.
   
6. Insert the rear light into the cutout.
   

Insert the rear light into the cutout in the direction of arrow

Slide the spacer and washer onto the retaining bolt, attach the knurled nut and tighten by hand.

Turn the bulb holder in the direction shown and remove from housing.

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I had similar symptoms - rapid flashing of directional when headlights on and brake depressed when making a left turn, both directional indicators in dash light dimly when brake depressed, "Check Traction Control System" indicator On even with ATC turned Off and "strange" indications in tail lights.

Check the pins in the connector at the Lamp Holder Assembly for your Rt. Tail Light for arcing and corrosion. (The female pin is in the vehicle harness connector and the male is part of the Lamp Holder Assembly.) If found, because the male connector is part of the Lamp Holder Assembly, you'll have to replace the Lamp Holder Assembly and the harness section coming in from the vehicle containing the female connector.

I just repaired this problem in the left tail light on my '01 van with a part from a '99 van I found at a local salvage yard.

Removing:

• Switch off all electrical consumers, switch off ignition key and remove ignition key.
• Remove rear luggage compartment side panel trim (left or right).

• Remove 3 nuts, arrows, and remove housing.
• Remove bulb holder.

Installing:

• Install bulb holder.
• Insert housing into body opening.
• Tighten nuts.
• Install applicable rear luggage compartment side panel trim.

Rear Light Bulb Holder Removing And Installing:
Removing:

• Disconnect electrical connector.
• Depress retainers, arrows, and remove bulb holder.

Installing:

• Install in reverse order of removal.

And the Center Mounted Brake Lamp.
High mount Brake Light Removing And Installing:
The high mount brake light is installed in the rear shelf.
Removing:

• Switch off all electrical consumers, switch off ignition key and remove ignition key.
• Disconnect electrical connector from high mount brake light.
• Remove rear shelf
• Un-clip high-mount brake light from rear shelf, arrows.
• Install in reverse order of removal.

NOTE: The bulb holder base plate contains soldered- in light emitting diodes (LEDs) that are not replaceable. In the event of LED malfunction, replace complete bulb holder.
Additional

Bad or borken wire harness in the steering coloum. check power to brake switch, should have power on one side, if not check the fuse if fuse is good and you have no power then your turn signal switch or harness is bad.

If the driver's side tail light is working, it's not a fuse. Use a test light to check for power at the bulb holder. One terminal will be for tail light, the other for brake/turn light. If the is constant power for tail light, replace bulb. If no power, trace wiring from bulb holder to driver's side junction. Probable broken wire between the two tail lights.

i had a similar problem. i thought i was buying the correct bulb at an auto store. Turned out, i needed to by the bulb directly from Jaguar as they are slightly different

The tail light housing bulb holders are notorious for not making good contact to the tail light housing. Remove the housing, and disconnect the electrical connector. Label each bulb holder prior to removal, with a marker pen. 1, 2, 3, upper, middle, lower, etc. Remove each bulb holder, by turning counter clockwise 1/2 turn, and withdraw holder. Inspect each contact. You can bend the contacts outward a tiny bit, just flex it a tiny bit, and check with an ohmmeter for contact. Also inspect the bulb holders for melting from bulb heat, so much so that the plastic holder, which contains the bulb contacts, no longer make proper contact to the bulb. Also check the bulbs with an ohmmeter to verify that the bulbs are good. When reinstalling the bulb holders, check that the little flanges on the holders are properly inserted into the tail light housing. Reconnect electrical connector, and reinstall housing into vehicle. On a further note, with the electrical connector disconnected from the housing, you can check for voltages from the connector pins to ground, using a voltmeter. Turn ignition switch to run position, turn on headlight, and turn on blinker, or use stick to push brake pedal, against front of seat, and verify voltage from pins to vehicle frame (or connector ground pin). If no voltage, then check fuses, or broken wiring. My experience, however, is poor connection from bulb holders to tail light housing.