Remove/Install Ignition Coils - AR15.12-P-2003W

Engine 276 in model 172 

Shown on model 172 with engine 276.9 

Fig 1: Ignition Coils Components Location - Engine 276 In Model 172 (Shown With Engine 276.9)

Courtesy of MERCEDES-BENZ USA

	Risk of injury  due to fan starting unexpectedly	Do not reach into the rotation or hazard area of the fan. Wear closed and close-fitting work clothes.	AS20.40-Z-0001-01A
	Risk of death  when working on component parts and systems with U >= 30 V alternating voltage (AC) or U >= 60 V direct voltage (DC)	Do not touch damaged or defective live component parts and lines or non-insulated electrical connections and lines.	AS00.00-Z-0035-01A
	Risk of injury.  Skin or eye injuries may result when handling hot or glowing objects.	Wear protective gloves, protective clothing and safety glasses, if necessary.	AS00.00-Z-0002-01A
Note	Information on preventing damage to electronic components due to electrostatic discharge		AH54.00-P-0001-01A
Note	Notes on avoiding damage through contamination and foreign objects		AH00.00-P-5000-01A
Note	Notes on avoiding damage to ignition system		AH15.10-P-0002-01V
	Remove/install
1	Switch off ignition and store transmitter key outside of transmission range (min. 2 m)
2.1	Remove front engine cover (1)	Engine 276.9 in model 172 Installation: The front engine cover is only installed after the engine test run.
2.2	Remove upper engine cover	Engine 276.8 in model 172 Installation: The top engine cover is only installed after the engine test run.
3.1	Remove air filter housing (2)	Engine 276.9 in model 172 For removal of the ignition coils (T1/1, T1/2, T1/3). Screw/bolt, air filter to cylinder head cover	*BA09.10-P-1001-01M
		Screw/bolt, air filter to air intake pipe support brace	*BA09.10-P-1002-01M
3.2	Remove right air filter housing	Engine 276.8 in model 172 For removal of the ignition coils (T1/1, T1/2, T1/3).	AR09.10-P-1150RKA
4.1	Remove the vacuum reservoir from the engine management control unit bracket	Engine 276.9 in model 172 When removing the ignition coils (T1/4, T1/5, T1/6).
4.2	Remove left-hand air filter housing	Engine 276.8 in model 172 When removing the ignition coils (T1/4, T1/5, T1/6).	AR09.10-P-1150RKA
5	Remove left or right soundproofing at the rail
6	Unlock and disconnect the electrical plug connections (4) for the ignition coils (T1/1, T1/2, T1/3, T1/4, T1/5, T1/6)
7	Unscrew the screws (5) at the ignition coils (T1/1, T1/2, T1/3, T1/4, T1/5, T1/6)	Screw/bolt, ignition coil to cylinder head cover	*BA15.10-P-1001-04A
8	Pull off and remove the ignition coils (T1/1, T1/2, T1/3, T1/4, T1/5, T1/6) including spark plug connectors (a) towards the top	Installation: Apply spark plug connector grease prior to installing the spark plug connector (a) to reduce the force required for connection and disconnection. Otherwise the spark plug connector will be damaged during renewed removal. Installation: Discharge approx. Fill 1 g of spark plug connector grease into the spark plug connector (a). Spark plug connector grease	*BR00.45-Z-1102-06A
9	Check the ignition coils (T1/1, T1/2, T1/3, T1/4, T1/5, T1/6) for damage	If a problem arises ↓ Replace the corresponding ignition coil (T1/1, T1/2, T1/3, T1/4, T1/5, T1/6).
10	Check spark plug connector (a) for damage	If a problem arises ↓ Replace the corresponding spark plug connector (a).
11	Install in the reverse order
	Check
12	Connect diagnostic system; read out fault memory.	Only if required.	AD00.00-P-2000-04A
	Risk of burn injuries  , suffocation and poisoning when working on the exhaust system and the components connected to it. Risk of suffocation and risk of poisoning caused by inhalation of gaseous and solid components of the exhaust. Risk of poisoning  caused by skin contact with solid components of the exhaust.	Wear protective clothing and safety glasses. Use the extraction system. Move people out of the hazard area.	AS49.00-Z-0001-01A
13	Risk of accident  from vehicle starting off by itself when engine running. Risk of injury  (bruises and burns) resulting from working on the engine while it is being started or when it is running. Conduct engine test run while checking for proper operation of the engine	Secure vehicle to prevent it from starting off by itself. Wear closed and snug-fitting work clothes. Do not touch hot or rotating parts.	AS00.00-Z-0005-01A