The Audi A4’s electrical system consists of several subsystems, including the engine control module (ECM), transmission control module (TCM), lighting system, charging system, and others.
A – battery B – starter C – alternator C1 – voltage regulator F125 – multifunction switch J60 – automatic transmission relay T2ab – 2-pin gray plug connector on the engine harness on the right side T6z – 6-pin red plug connector at the humidifying box, junction box for electrical connections T10v – 10-pin brown plug connector on the right side, station A T10x – 10-pin blue plug connector on the right side, station A 11 – ground point, in the battery box 81 – ground connection, at the distribution panel for wire groups 114 – ground connection, in the wire group for the automatic transmission
- vehicles with automatic transmission ** – vehicles with manual transmission
The ECM is responsible for controlling various engine functions, such as fuel injection, ignition timing, and emissions. It receives input signals from sensors throughout the engine and uses this information to adjust the engine’s performance.
The TCM controls the transmission and receives input signals from various sensors, such as the throttle position sensor and vehicle speed sensor. It uses this information to determine the appropriate shift points and engage the appropriate gears.
The lighting system includes the headlights, taillights, turn signals, and other exterior lights. It is controlled by the light switch and various relays and fuses.
The charging system includes the battery, alternator, and voltage regulator. The alternator charges the battery while the engine is running and the voltage regulator ensures that the electrical system operates at the correct voltage.
Overall, the car wiring diagram for an Audi A4 is a complex document that requires a good understanding of automotive electrical systems to properly diagnose and repair any issues.
