If a rodent chews through your engine harness, or you are building a custom swap harness, the pinout datasheet is your bible. It tells you wire colors (if OEM info is included) and pin locations.
Identifying which pins send signals from sensors (MAF, MAP, O2 sensors) to the ECU to diagnose, for instance, a "No Signal" fault code. Bosch Ecu Pinout Datasheet
Look for 5V Ref (Five-volt reference loop for sensors), GND Ref (Sensor clean ground), and individual inputs like IAT (Intake Air Temp) or MAF (Mass Air Flow). If a rodent chews through your engine harness,
Once you have the correct document, understanding its symbols and layout is critical. Automotive wiring diagrams are logical maps, not physical representations of the car. GND Ref (Sensor clean ground)
