520d

various systems. Battery replacement and charging system checks. Sensor diagnostics, including MAF, oxygen sensors, and ABS sensors. ECU (Engine Control Unit) troubleshooting. Cooling and Heating Radiator and thermostat replacement. Coolant

diagnostic codes for sensors like MAF or O2 sensors. Cooling System Failures: Inspect radiator, thermostat, water pump, and coolant hoses. Replace any worn parts. Electrical and Electronic Problems Check Engine Light (CEL) On: Use diagn