Removal and installation of rear wheel-speed sensor - RA42001240714X(42-0714)

Operation no. of operation texts and work units or standard texts and flat rates: 42-9803.

1. Models 124, 201 
   Fig 1: Identifying Rear Wheel-Speed Sensor Components - Models 124, 201

   Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

   Ignition	OFF  .
   Rear seat and rear seat backrest	remove, install.
   Wire connector (L6x1)	open, reconnect.
   Clips (42)	loosen, fasten.
   Lead (27)	remove downwards through the rubber grommet (28) in the frame floor.
   Self-locking hexagon socket screw (30)	unscrew, replace, 8 Nm.
   Rear wheel-speed sensor (L6)	remove complete with lead (27). When installing, ensure that no metallic foreign bodies are located on the magnetic edge of the wheel speed sensor and that the O-ring (29) is not damaged. The flange of the wheel speed sensor must abut the rear axle casing (67).
   O-ring (29)	check, replace if required.
   Rear axle rotor	check for any damage, contamination and firm seating of the driveshaft and number of teeth.
   Model 124 (except 124.034), 201  Test program	perform (42-0720).
   Model 124.034  Fault memory	read out, then erase (Chassis Diagnosis Manual, Volume 2).

   NOTE: Since 03/86 a modified wheel speed sensor with a steel flange (previously plastic) has been installed. The steel and plastic versions of the wheel speed sensors are not interchangeable owing to different dimensions.
   Fig 2: Identifying Wheel Speed Sensor Dimensions

   Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
2. Models 129, 140 

   Preceding work:

   Remove, install plastic cover above plug connection of rear axle to distributor (X62/8) and fuel pump package.

   Operation no. of operation texts and work units or standard texts and flat rates:

   Fig 3: Identifying Rear Axle Distributor - Models 129, 140

   Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

   Ignition	OFF  .
   Self-locking hexagon socket screw	unscrew, screw in at rear axle wheel speed sensor (L6). When installing, replace self-locking hexagon socket screw, 8 Nm.
   Rear axle wheel speed sensor (L6)	remove vertically out of rear axle casing. When installing, ensure that no metallic foreign bodies are located on the magnetic edge of the wheel speed sensor and that the O-ring is not damaged, replace O-ring if required. The flange of the wheel speed sensor must abut the rear axle casing.
   Rear axle rotor	check for any damage, contamination and firm seating on the driveshaft and number of teeth.
   Hose tie (arrow)	slacken, tighten in guide rail.
   Plug connection of rear axle/distributor (X62/8)	Open bayonet lock and detach plug connection. Slacken cover (123) of plug connection distributor (122) by one notch.
   Plug (L6)	detach from plug connection distributor (122). When assembling, ensure that the plug assignment is not interchanged (note letter marking).
   Model 129.060/061/066  Test program	perform (42-0720).
   Model 129.058/063, 140  Fault memory	read out, then erase (Chassis Diagnosis Manual, Volume 2).

3. Model 202 
   Fig 4: Identifying Plug Connector And Rear Wheel Speed Sensor - Model 202

   Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

   Ignition	OFF  .
   Luggage compartment floor trim and lower cover panel	remove, install.
   Plug connector (X62/11)	unplug, replug.
   Self-locking Allen bolt	unscrew from rear wheel-speed sensor, reinstall. Use new self-locking Allen bolt for reassembly, 8 Nm.
   Rear wheel-speed sensor (L6)	remove and re-insert vertically at the front axle housing. When installing, ensure that the sensor's magnetic edge is free of metallic particles, and that the O-ring is undamaged, replacing O-ring where necessary. The flange of the wheel-speed sensor must rest against the front axle housing. Do not use force!
   Rear-axle rotor	check for damage and contamination, ensure tight fit on drive shaft, check number of teeth, test.
   Fault memory	read out, then erase (Chassis Diagnosis Manual, Volume 2).

4. Rotor to rear axle assignments on Models 124,129, 140, 201, 202 

   Ratio i		Toothed wheel on drive pinion gear Number of teeth (rotor)
   Production/ABS	with ASD
   2.24	-	43
   2.47	-	39
   2.65	2.65	36
   2.72	-	35
   2.82	-	34
   2.87	2.87	33
   2.88	2.88
   3.06	-	31
   3.07	3.07
   3.23	-	30
   3.27	3.27	29
   3.29	3.29
   3.46	3.46	28
   3.42
   3.64	3.67	26
   3.67
   3.69	3.69	26
   3.91	3.92	24
   4.18	4.18	23