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

ENGINE 272.942 in MODEL 171.454 

ENGINE 272.963 in MODEL 171.456 

Fig 1: Identifying Heated O2 Sensor Components

Courtesy of MERCEDES-BENZ USA

	Remove/Install
	Risk of injury  to skin and eyes from handling hot or glowing objects.	Wear safety gloves, protective clothing and safety glasses, if necessary.	-
	Risk of death  caused by vehicle slipping or toppling off of the lifting platform.	Align vehicle between the columns of the lifting platform and position the four support plates at the lifting platform support points specified by the vehicle manufacturer.	-
1	Raise vehicle.		AR00.60-P-1000V
2	Detach the rear section of the lower engine compartment paneling	Installation:  Install engine compartment paneling only after the engine test run.	AR61.20-P-1105V
3	Unclip electrical connector for the respective O2Unclip sensor from retaining clamp
4	Unclip electrical line for the respective O2Unclip sensor downstream of catalytic converter from the retaining clamp
5.1	Unclip the electrical line for the respective O2sensor upstream of the catalytic converter from the retaining clamp at the transmission	On vehicles with retaining clamp (up to vehicle ID number 042765) Installation:  The electrical line for the respective O2sensor upstream of the catalytic converter must not be clipped back into the retaining clamp, as otherwise the electrical line can be damaged.
6	Detach the electrical connector of the respective O2 sensor
7	Remove the respective O2 sensor	Installation:  Coat the thread with heat resistant lubricant.
			*BA14.00-P-1002-01A
		Ring wrench socket	Fig 2
		Paste	*BR00.45-Z-1005-06A
8	Install in the reverse order
9	Read out fault memory
	Connect STAR DIAGNOSIS and read out fault memory		AD00.00-P-2000-04A
		STAR DIAGNOSIS diagnosis system	*WH58.30-Z-1048-13A
	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 engine	Secure vehicle to prevent it from moving. Wear closed and snug-fitting work clothes. Do not grasp hot or rotating parts.	-
10	Conduct engine test run and inspect exhaust system for leaks

Fig 2: Identifying Ring Wrench Socket (000 589 71 03 00)

Courtesy of MERCEDES-BENZ USA