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Check / adjust sensor setting of Distronic (DTR) - AR30.30-P-1000R

MODEL 164, 209, 211, 215, 216, 219, 220, 221, 230, 240, 251 with CODE (219) Distronic (DTR) 

MODEL 216, 221 with CODE (233) Distronic Plus 

MODEL 164, 251 up to model year 2009 

Shown on model 230 with arched radar sensor 

Fig 1: Identifying DTR Radar Sensor Components
G07587481Courtesy of MERCEDES-BENZ USA

shown on model 230 

Fig 2: Identifying Headlamp Adjustment Testing Unit Components
G07587482Courtesy of MERCEDES-BENZ USA

Vehicle with an arched radar sensor 

Fig 3: Adjusting Distronic DTR Sensor Setting - Arched Radar Sensor
G07587483Courtesy of MERCEDES-BENZ USA

Vehicle with a radar sensor that is not arched (flat) 

Fig 4: Adjusting Distronic DTR Sensor Setting - Flat Radar Sensor
G07587484Courtesy of MERCEDES-BENZ USA
Fig 5: Identifying Center Of Reticule
G07587485Courtesy of MERCEDES-BENZ USA
MEASURING Measuring, adjusting     
DANGER Risk of injury  to skin and eyes from laser beams Never look directly into the laser beam. Do not attempt to suppress natural reflex of eyelids.
Avoid direct skin contact with the laser beam.
If damage to the eye is suspected, consult an eye specialist immediately.		 AS30.30-Z-0001-01A
IMPORTANT Initialization of the DTR control unit (A89n1) is necessary after:
  • Replacement of the DTR controller unit (A89)
  • Replacement of the steering column tube module (N80)
  • Replacement of the rotational speed sensor and lateral acceleration (B24/15) (model 209, 211, 215, 216, 219, 220, 221, 230, 240)
  • Replacement of the yaw rate sensor for lateral and longitudinal acceleration (B24/15) (model 164, 251)
    
IMPORTANT Adjustment of the DTR radar sensor (A89b1, B29) is necessary after:
  • Replacement of or detachment/attachment of the DTR controller unit (A89)
  • Mechanical damage to the DTR radar sensor (A89b1, B29)
  • Accident repair in front area
  • Alterations on the camber, track width, caster or of the level of the vehicle at the front or rear axle
    
1 Conduct quick test with STAR DIAGNOSIS    
REFER TO SELF-DIAGNOSTIC SYSTEMS Connect STAR DIAGNOSIS and read out fault memory AD00.00-P-2000-04A
DANGER Risk of injury  caused by fingers being pinched or crushed  when removing, installing or aligning hoods, doors, trunk lids, liftgates or sliding roof Keep body parts and limbs well clear of moving parts. AS00.00-Z-0011-01A
2 Open engine hood Model 164 AR88.40-P-1000GZ
Model 209 AR88.40-P-1000Q
Model 211 AR88.40-P-1000T
Model 219 AR88.40-P-1000TX
Model 215, 220
Model 216, 221		 AR88.40-P-1000M
Model 230 AR88.40-P-1000R
Model 240 AR88.40-P-1000H
Model 251 AR88.40-P-1000RT
3.1 Remove radiator grille Model 164.1 up to model year 09, 164.8 AR88.40-P-4001GZ
Model 164.1 as of model year 09
Model 216		 AR88.40-P-4001GZA
Model 219 AR88.40-P-4001TX
Model 230 AR88.40-P-4001R
Model 251 AR88.40-P-4001RT
3.2 Remove bumper Model 240 AR88.20-P-2000H
4 Check DTR radar sensor (A89b1, B29) INSPECT Only conduct visual test on mechanical damages.
Check if:
  • DTR radar sensor (A89b1, B29) is damaged or dirty
  • Connectors (9) are loose

IMPORTANT On the DTR radar sensor (A89b1) only one connector is available.
  • Clips (10) for mounting adjusting bolts (3a, 3b, 3c) are loose or defective.
  • Spacers between clips (10) for mounting adjusting bolts (3a, 3b, 3c) and the DTR radar sensor (A89b1, B29) are available.
5 Perform a wheel alignment check Model 164 AR40.20-P-0200GZ
Model 209 AR40.20-P-0200P
Model 211 AR40.20-P-0200T
Model 219 AR40.20-P-0200TX
Model 215, 220 except code (979) special protection version except code (Z07) highest protection AR40.20-P-0200I
Model 220 with code (979) special protection version with code (Z07) highest protection AR40.20-P-0200MB
Model 216, 221 AR40.20-P-0200SX
Model 230 AR40.20-P-0200R
Model 240 AR40.20-P-0200H
Model 251 AR40.20-P-0200RT
6 Align front wheels to the geometric driving axle IMPORTANT The front wheels must be aligned to the geometric driving axle.  
7 Remove front measuring heads from the quick tensioning holders    
8 Fit the measuring rods (1) onto the quick tensioning holders in place of measuring heads    
9 Attach the spacer ring (8) to the DTR radar sensor (A89b1) Only for vehicles with non-arched (flat) DTR radar sensor (A89b1).
IMPORTANT Use a spacer ring (8) from the Distronic adjusting device.
Distronic adjustment device gotis://E_30_01.0 		  
10 Align headlamp setting/test equipment (2) with the guide rods (1) and adjust the height to the position of the DTR radar sensor (A89b1, B29) IMPORTANT Observe operating instructions of headlamp adjustment testing unit (2).
IMPORTANT Headlamp adjustment testing unit (2) must stand on even surface, parallel to contact patch.
IMPORTANT Set headlamp range adjustment at headlamp adjustment testing unit (2) to "0".
Headlamp aimer - mobile gotis://E_82_01. 		  
11 Fit optical adjusting device (5) with distance pins (5b) onto DTR radar sensor (A89b1, B29) and firmly suction using the SPECIAL TOOL hand vacuum pump (6) NOTES In order to secure the optical adjusting device (5) from falling down, hang up fastening strap (4) at vehicle.
IMPORTANT In order to guarantee a secure seating of optical adjusting device (5) on DTR radar sensor (A89b1, B29), Vaseline should be applied to the rubber lip of suction bell and the SPECIAL TOOL hand vacuum pump (6) should be evacuated from 600 to 700 mbar.		  
SPECIAL TOOL Hand vacuum pump
Distronic adjustment device gotis://E_30_01.0 		 Fig 6
12 Align headlamp adjustment testing unit (2) to vehicle IMPORTANT For alignment look into overhead mirror (2/1). Align headlamp adjustment testing unit (2) by rotating (arrow) around the vertical axis, in such a way, that the right and the left sounding rods (1) overlap with mirror reticule (2/1a) in the overhead mirror (2/1).  
13 Connect optical adjusting device (5) to cigarette lighter IMPORTANT On vehicles with code 889 Keyless Go: press the Keyless Go start and stop pushbutton once without depressing the brake pedal - the laser in the optical adjusting device (5) is activated.
IMPORTANT On vehicles without Keyless Go: turn ignition key to position "1" - the laser in the optical adjusting device (5) is activated.		  
14 Connect STAR DIAGNOSIS and starting off automatic calibration level Only for vehicles with code 489, AIRmatic or with code 487, Active Body Control (ABC).  
15 Read off point of impact of laser beam in headlight adjustment testing unit (2) IMPORTANT Point of impact and cross-hair center (7) must match.  
16 Adjust horizontal adjustment of DTR radar sensor (A89b1, B29), for this step bring point of impact to height of reticule center (7) by twisting adjusting bolt (3a) at DTR radar sensor (A89b1, B29) in the headlamp adjustment testing unit (2) IMPORTANT In case of a correction, ensure that adjustment screw (3a) is turned counterclockwise by one piece first (eliminate threaded play).
IMPORTANT The adjusting bolt (3b) is only to be twisted in the case, that range of adjustment of the adjusting bolts (3a, 3c), would not be adequate for a correction.		  
17 Set vertical adjustment of DTR radar sensor (A89b1, B29); for this step point of impact must overlap with the reticule center (7) in the headlamp adjustment testing unit (2) through twisting of the adjusting bolt (3c) at the DTR radar sensor (A89b1, B29) IMPORTANT For vertical alignment of optical adjusting device (5), observe bubble level (5a). In case of a correction, ensure that adjustment screw (3c) is turned counterclockwise by one piece first (eliminate threaded play).
IMPORTANT The adjusting bolt (3b) is only to be twisted in the case, that range of adjustment of the adjusting bolts (3a, 3c), would not be adequate for a correction.		  
18 Remove optical adjusting device (5) IMPORTANT Remove vaseline from the DTR radar sensor (A89b1, B29).  
19 Remove the spacer ring (8) of the DTR radar sensor (A89b1) Only for vehicles with non-arched (flat) DTR radar sensor (A89b1).
NOTES The spacer ring (8) must be removed to ensure that DTR radar sensor (A89b1) functions correctly.		  
20 Reset the learning values with STAR DIAGNOSIS    
21.1 Install radiator trim Model 164.1 up to model year 09, 164.8 AR88.40-P-4001GZ
Model 164.1 as of model year 09
Model 216		 AR88.40-P-4001GZA
Model 219 AR88.40-P-4001TX
Model 230 AR88.40-P-4001R
Model 251 AR88.40-P-4001RT
21.2 Install bumper Model 240 AR88.20-P-2000H
22 Close engine hood Model 164 AR88.40-P-1000GZ
Model 209 AR88.40-P-1000Q
Model 211 AR88.40-P-1000T
Model 219 AR88.40-P-1000TX
Model 215, 220
Model 216, 221		 AR88.40-P-1000M
Model 230 AR88.40-P-1000R
Model 240 AR88.40-P-1000H
Model 251 AR88.40-P-1000RT
Fig 6: Identifying Hand Vacuum Pump (001 589 73 21 00)
G07587486Courtesy of MERCEDES-BENZ USA
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