Working on a 2008 Mercedes CLS550. We diagnosed an issue with the rear trunk lid not wanting to close, diagnosed an issue with the TPMS (tire pressure monitor system) light flashing, we diagnosed an inoperative driver's door lock, tested the starting and charging system due to the vehicle being slow to crank, inspected the brake system due to a squeal in the morning when backing up, inspected for light bulbs out due to a bulb malfunction light on and inspected for needed maintenance. We replaced the trunk lock actuator, replaced the battery, replaced the rear brake pads and rotors, replaced the camshaft end plugs and the crankcase vent valve, replaced the engine air filter and replaced the left front outer door handle.