Retrofitting Radio Systems
General Information
Before installing radios and telephone systems (radio
systems), disconnect the negative terminal of the Battery -A-.
Refer to
→Electrical Equipment; Rep. Gr.27.
Use the applicable wiring diagrams. Refer to
→ Wiring diagrams, Troubleshoo
Note
On vehicles with a high-voltage system but without a heat
pump (for example on Audi A3 e-tron, Audi Q5 hybrid, Audi A6
hybrid and Audi A8 hybrid) no check valves are installed in the
refrigerant circuit. On these vehicles valves are installed in
the refrigerant circuit which regulat