Changed my battery and now my radio, a/c and heat won't work. Instrument panel shows the battery light, ESC, and brake light???

were your battery cable ends corroded (blueish/white)??? Are your battery cables tight free from moving???

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).

Fuses: Fuse arrangement in fuse panel, behind instrument cluster, left
Fuse Arrangement In Fuse Panel

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

check your ground should have one for brake lights

Hi there, have you tried the radio fuse and lighter fuse as when tail lights and dash lights wont work it is normally one of those.

clean bulbs socket out using the electronic spray cleaner for electrical connectors.

There could be a fusible link under the hood off the starter relay that is burnt out.

I think I have found the problem. When I wiggle the ignition switch the turn signals and radio go on and off so I feel the issue is in the ignition switch. From what I understand the actual electronics for the switch are at the base of the sterring column behind the lower dash panel and is connected by a rod that may need adjusting.

it seems to be a wiring problem .get the wiring checked.