Notes on avoiding damage to ignition system - AH15.10-P-0002-01V

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ENGINE 133, 152.9, 157, 177, 178, 270, 272, 273, 274, 276, 278

Shown on ENGINE 272

Fig 1: Identifying Electrical Connector And ME-SFI (ME) Control Unit - Shown On Engine 272

Courtesy of MERCEDES-BENZ USA

Shown on ENGINE 272

Fig 2: Identifying Spark Plug Connector And Cylinder Ignition Coils - Shown On Engine 272

Courtesy of MERCEDES-BENZ USA

Before detaching the electrical connection (R) from the ME-SFI [ME] control unit (N3/10 or N3/34) turn the key in the ignition lock to position "0".
Before detaching the electrical connection (L) from the ME-SFI [ME] control unit (N3/10 or N3/34), disconnect the battery.
Install genuine parts only into the ignition system.
Do not operate the ignition system without fully connected lines or without the spark plug connector (a).
Do not detach the electrical connections from the ignition coils (T1 1 to T18) at starting speed or when the engine is running.
Do not remove the ignition coils (T1 1 to T18) from the spark plugs at starting speed or when the engine is running.