Remove/install heated O2 sensor - AR07.52-P-5303SX

ENGINES 156, 157, 272, 273, 275, 276, 278 in MODEL 221

ENGINES 156, 157, 273, 275, 278 in MODEL 216

Shown on model 221.171

Fig 1: Identifying O2 Sensor Components

Courtesy of MERCEDES-BENZ USA

Fig 2: Identifying O2 Sensor Components

Courtesy of MERCEDES-BENZ USA

Shown on model 221.176

Fig 3: Identifying O2 Sensor Components

Courtesy of MERCEDES-BENZ USA

	Remove/install
	Risk of injury to skin and eyes caused by handling hot or glowing objects.	Wear safety gloves, protective clothing and safety glasses, if necessary.	AS00.00-Z-0002-01A
1	Switch off ignition
2	Remove bottom engine compartment paneling	Vehicles without code (Z07) Top protection	AR61.20-P-1105SX
2	Remove bottom engine compartment paneling	Vehicles with code (Z07) Top protection	AR61.20-P-1105SXS
3.1	Unclip electrical connector and electrical feed line for corresponding O2 sensor out of retaining clamps on the transmission	Except model 221.095 /195
3.2	Unclip electrical connector and electrical feed line for corresponding O2 sensor out of the retaining clamps on the transmission or on the power distributor for the power electronics	Model 221.095 / 195
4	Unclip electrical connector and electrical feed line for corresponding O2 sensor out of the retaining clamps at the rear on the corresponding charge air cooler on the left or right	Engine 275
5	Disconnect electrical connector for corresponding O2 sensor
6	Remove respective O2 sensor	Installation: Coat thread with paste.
		O2 sensor on CAT for engine 156, 272, 273, 275, 276	*BA14.00-P-1002-01A
		Diagnostic sensor downstream of CAT for engine 156, 272,	*BA14.00-P-1004-01A
		Control sensor upstream of CAT for engine 156, 157, 272, 276, 278	*BA14.00-P-1005-01A
			*000589710300
		Paste	*BR00.45-Z-1005-06A
7	Install in the reverse order
8	Read out fault memory with STAR DIAGNOSIS and erase if necessary		AD00.00-P-2000-04A
	Risk of accident caused by vehicle starting off by itself when engine is running. Risk of injury caused by contusions and burns during starting procedure or when working near the engine as it is running	Secure vehicle to prevent it from moving by itself.	AS00.00-Z-0005-01A
		Wear closed and snug-fitting work clothes.
		Do not touch hot or rotating parts.
9	Test run engine and check exhaust system for leaks

O2 sensor

Number	Designation		Engine 156	Engine 272	Engine 273	Engine 275
BA14.00-P-1002-01A	O2 sensor on catalytic converter	Nm	50	50	50	50
BA14.00-P-1004-01A	Diagnostic sensor downstream of catalytic converter	Nm	50	50	-	-
BA14.00-P-1005-01A	Control sensor upstream of catalytic converter	Nm	50	50	-	-

O2 sensor

Number	Designation		Engine 276	Engines 157, 278
BA14.00-P-1002-01A	O2 sensor on catalytic converter	Nm	50	-
BA14.00-P-1004-01A	Diagnostic sensor downstream of catalytic converter	Nm	-	50
BA14.00-P-1005-01A	Control sensor upstream of catalytic converter	Nm	50	50

Fig 4: Identifying Box Wrench Bit (000 589 71 03 00)

Courtesy of MERCEDES-BENZ USA

Repair materials

Number	Designation	Order number
BR00.45-Z-1005-06A	Paste, hot lubrication 1 kg, DB supply specification 6879.20	A 000 989 76 51