Turn signal light in left mirror

electrical fault breaker is powering the indicator. usually an earthing problem. could be in the light socket housing or the wiring.

The signal flasher. Maybe a bulb burned out.

change the bulb if still out then check and test socket/ground wiring/wire harness for damage

Sounds like a ground problem to me. Bulbs are not getting there ground to complete the circuit so they backfed through the other bulbs.

Try cleaning the fuse contacts, it may not work but is worth a try. I used an ignition breaker points file that i ground a bit off one side so it would fit in the contact slots when the left turn signal and brake light wouldn't work and it was successful on my 2009 grand caravan. I didn't know there was a problem until i hooked up the trailer and saw it had no left brake/stop lights. I used a small test indicator that plugs into the trailer connector and has 4 leds which light up when each item is activated. use a trailer connector kit that has the male and female connector connected to a 4 foot long wire set I bought at Walmart. I plug it into the car connector with the test indicator plugged in the other end and held on the rear window by the wiper blade so i can see in the rear view mirror if all the lights work. For a sedan I put in on the ground, anchored by any tool handy, so i can see it in the side mirror. It beats running back and forth to see if I made a repair.

When you are talking about "indicators" we could assuming that your are refer about signal lights. This work with "flashers" devices.

For 1996 Audi A4 2.8L SFI 6cyl the Flasher is located in front seating area, driver side, under dash, behind dash lower panel, mounted above driver side of steering column.

About generic fuses, open the driver side door. Remove panel on left side of dash. Fuse box is behind panel:

Fuse # / Description / Amps
1 / Heated washer jets / 5
2 / Turn signals flasher unit / 10
3 / Headlight washer, illumination of glove compartment, engine compartment, climate control, automatic transmission, instrument cluster / 5
4 / License plate light / 5
5 / Instrument cluster, seat heating, test connection for cruise control, bulb monitor for auto-check control, Automatic transmission display, switch lighting, mirror switches and actuators, airbag warning light, outside temperature indicator, Climate control / 10
6 / Central locking system / 5
7 / Anti-lock brake system / 10
8 / Vacant
9 / Mirror heating / 10
10 / Vacant
11 / Cruise control (automatic transmission) / 5
12 / On board diagnostic system / 10
13 / Brake lights / 10
14 / Interior lights, reading lights, anti-theft alarm system, vanity mirror / 10
15 / Instrument cluster, power windows, climate control, automatic transmission / 10
16 / Anti-lock brake system, Anti-Slip-Regulation / 5
17 / Heated door locks / 10
18 / High beam right / 10
19 / High beam left / 10
20 / Low beam right / 15
21 / Low beam left / 15
22 / Tail and side marker right / 5
23 / Tail and side marker left / 5
24 / Wiper and washer system / 25
25 / Blower for heating, climate control / 30
26 / Rear window defogger, mirror heating / 30
27 / Rear window wiper / 15
28 / Fuel pump / 15
29 / Engine timing / 20
30 / Sun roof / 20
31 / Tail lights, cruise control, automatic transmission / 15
32 / Engine timing / 20
33 / Cigarette lighter / 15
34 / Engine timing / 15
35 / Trailer receptacle / 30
36 / Fog lights / 15
37 / Radio / 20
38 / Luggage compartment light, central locking system / 15
39 / Emergency flasher / 15
40 / Horn / 25
41 / Anti-lock brake system / 25
42 / Vacant
43 / Vacant
44 / Seat heating / 30

Hope this helps (remember to rate and comme this free answeer).

If the turn signal bulbs are the same as the turn signal bulbs it would indicate the brake light on the left is not working. If the brake lights AND the right turn signal come on it could indicate a wire is getting a cross feed from an improper source. If you are comfortable with electrical systems - If you have a tow package you may want to check the wires to the trailer. Otherwise have it checked by an electrical shop.

Replace both sides with correct dual element bulbs which may be the culprit here

Usually when your signal blinks rapidly it indicates a blown bulb.   Switch on your four-way flashers and check your bulbs at each corner.  On the brake light staying lit, check to see if the left-rear bulb is installed correctly and is the correct bulb for the application.  I've seen people force bulbs in sockets causing the braking element of the bulb to light instead of the parking element.  The braking element is much brighter than the parking element.

Find the ground wire on one of the lights and add another ground wire to a good clean metal surface and see if that fixes the problem. It defently sounds like a ground problem at one of the lights.