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Checking Brake Booster - AR43.10-P-0325MFA

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Model 118, 177, 247 

G16050145Courtesy of MERCEDES-BENZ USA
G16050146Courtesy of MERCEDES-BENZ USA
CAUTION Risk of poisoning  from swallowing brake fluid. Risk of injury  from skin and eye contact with brake fluid Only pour brake fluid into suitable and appropriately marked containers. Wear protective clothing and eye protection when handling brake fluid. AS42.50-Z-0001-01A
Notice  Notes on externally invisible brake fluid loss   AH42.10-P-9406-02A
Notice  Notes on repairs to brake system   AH42.00-P-0003-01A
Notice  Brake fluid notes   AH42.50-P-0001-01A
REMOVING Remove     
1 Remove left front wheel and tire assembly.   AR40.10-P-1102MFA
2 Remove heat shield for firewall. Model 118, 177, 247 with engine 260
Model 118, 177, 247 with engine 282
Model 118, 177, 247 with engine 654
Model 247 with engine 608		  
    Model 247 with engine 608 AR49.10-P-0001MFE
    Model 118, 177, 247 with engine 282 AR49.10-P-0001MFD
    Model 118, 177, 247 with engine 260 AR49.10-P-0001MFC
    Model 118, 177, 247 with engine 654 AR49.10-P-0001MFF
3 Remove cover above brake fluid expansion reservoir.    
4 Clean area around cap on brake fluid expansion reservoir. NOTES
Before opening, clean the area surrounding the cap thoroughly.
Otherwise dirt particles in the hydraulic component parts can result in malfunctions and total failure of the brake system. Assembly cleaner		 *BR00.45-Z-1028-04A 
5 Unscrew cap on brake fluid expansion reservoir and suction off some brake fluid. SPECIAL TOOL Hand pump Fig 1
INSPECT Check     
WARNING 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. 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
6 Connect filling unit to brake fluid reservoir.    
REFER TO SPECIAL TOOLS 000 588 16 82 00 Filling unit   WS25.00-P-0038B
REFER TO CAPACITIES & SPECIFICATIONS General brake fluid   BB00.40-P-0330-01A
REFER TO CAPACITIES & SPECIFICATIONS Brake fluids (DOT 4 plus)   BB00.40-P-0331-00A
7 Reduce vacuum in brake booster (4) by depressing brake pedal several times.    
8 Connect vacuum tester (9) with test   AR43.10-P-0024-01V 
  connection (5) at brake booster (4). SPECIAL TOOL Tester Fig 5
    SPECIAL TOOL Test connection Fig 4
9 Remove bleed screw at front brake caliper on driver's side and connect test equipment
(7).		   WS42.00-P-0115B
REFER TO SPECIAL TOOLS 000 588 28 21 00 Test equipment    
    NOTES
Use correct connection fitting (pitch, centering cone, etc.).
Leaks and measurement errors can otherwise occur.		  
10 Bleed test equipment (7).    
REFER TO SPECIAL TOOLS 000 588 28 21 00 Test equipment   WS42.00-P-0115B
11 Connect pedal force meter (8) at brake pedal. IMPORTANTCommercially available devices/tools  Pedal force meter (8)  
12 Start the engine and generate specified vacuum. IMPORTANT If this vacuum is not reached or it drops immediately, the seal between the brake booster (4) and master brake cylinder may be damaged or the check valve (6) may be defective.  
    HAND-HELD TESTER Model 118.### 1# with engine 260 Model 118.### 1# with engine 282 except code 950 (AMG sport package) except code U29 (Sports braking system) Model 118.### 1# with engine 282 with code 950 (AMG sport package) Model 118.### 1# with engine 282 with code U29 (Sports braking system) Model 118.### 1# with engine 608 except code 950 (AMG sport package) except code U29 (Sports braking system) Model 118.### 1# with engine 608 with code 950 (AMG sport package) Model 118.### 1# with engine 608 with code U29 (Sports braking system) Model 118.### 2# Brake line pressure *BE43.10-P-1004-01J 
    HAND-HELD TESTER Model 177.### 1# with engine 260 Model 177.### 1# with engine 282 except code ME08 (Hybrid drive 75-84 kW VARIANT (INCLUDING PLUGIN)) Model 177.### 1# with engine 608 Model 177.### 2# with engine 260, 608 Model 177.### 2# with engine 282 except code ME08 (Hybrid drive 75-84 kW VARIANT (INCLUDING PLUGIN)) Brake line pressure *BE43.10-P-1004-01H 
    HAND-HELD TESTER Model 247.### 1# with engine 282 Model 247.### 1# with engine 608 Model 247.### 2# Model 247.0## 1# with engine 654 except code U29 (18-inch brake system) Model 247.0## 1# with engine 654 with code U29 (18-inch brake system) Brake line pressure
If the vacuum is not reached.
↓
Switch off engine, and check seal between brake booster (4) and master brake cylinder as well as the check valve (6).		 *BE43.10-P-1004-01I 
      AR42.10-P-0300MFA
      AR43.10-P-0023MFA 
13 Replace seal between brake booster (4) and master brake cylinder. If the specified vacuum has not been reached or if it drops off straight away and the check valve (6) is not defective.  
      AR42.10-P-0300MFA
14 Apply specified force to brake pedal and read off line pressure at test equipment (7).    
REFER TO SPECIAL TOOLS 000 588 28 21 00 Test equipment   WS42.00-P-0115B
    HAND-HELD TESTER Model 118.### 1# with engine 260 Model 118.### 1# with engine 282 except code 950 (AMG sport package) except code U29 (Sports braking system) Model 118.### 1# with engine 282 with code 950 (AMG sport package) Model 118.### 1# with engine 282 with code U29 (Sports braking system) Model 118.### 1# with engine 608 except code 950 (AMG sport package) except code U29 (Sports braking system) Model 118.### 1# with engine 608 with code 950 (AMG sport package) Model 118.### 1# with engine 608 with code U29 (Sports braking system) Model 118.### 2# Brake line pressure *BE43.10-P-1004-01J 
    HAND-HELD TESTER Model 177.### 1# with engine 260 Model 177.### 1# with engine 282 except code ME08 (Hybrid drive 75-84 kW VARIANT (INCLUDING PLUGIN)) Model 177.### 1# with engine 608 Model 177.### 2# with engine 260, 608 Model 177.### 2# with engine 282 except code ME08 (Hybrid drive 75-84 kW VARIANT (INCLUDING PLUGIN)) Brake line pressure *BE43.10-P-1004-01H 
    HAND-HELD TESTER Model 247.### 1# with engine 282 Model 247.### 1# with engine 608 Model 247.### 2# Model 247.0## 1# with engine 654 except code U29 (18-inch brake system) Model 247.0## 1# with engine 654 with code U29 (18-inch brake system) Brake line pressure *BE43.10-P-1004-01I 
    SPECIAL TOOL Adapter for brake pedal winch Fig 3
    SPECIAL TOOL Pedal arrester
If the line pressure is not reached,
↓
replace brake booster (4).		 Fig 2
      AR43.10-P-0350MFA 
15 Switch off engine.    
16 Remove pedal force meter (8) from brake pedal. IMPORTANTCommercially available devices/tools  Pedal force meter (8)  
17 Disconnect vacuum tester (9) with test connection (5) from brake booster (4).   AR43.10-P-0024-01V 
    SPECIAL TOOL Tester Fig 5
    SPECIAL TOOL Test connection Fig 4
18 Disconnect test equipment (7) with connection fitting and screw in bleed screw all the way at brake caliper on driver's side.    
REFER TO SPECIAL TOOLS 000 588 28 21 00 Test equipment   WS42.00-P-0115B
19 Bleed brake caliper on the driver's side.    
REFER TO SPECIAL TOOLS 000 588 16 82 00 Filling unit   WS25.00-P-0038B
      AR42.10-P-0010-02MFA
    TORQUE SPECIFICATION Bleed screw at brake caliper *BA42.10-P-1004-10ZA 
20 Disconnect filling unit from brake fluid reservoir.    
REFER TO SPECIAL TOOLS 000 588 16 82 00 Filling unit   WS25.00-P-0038B
REFER TO CAPACITIES & SPECIFICATIONS General brake fluid   BB00.40-P-0330-01A
REFER TO CAPACITIES & SPECIFICATIONS Brake fluids (DOT 4 plus)   BB00.40-P-0331-00A
21 Check and correct fluid level in brake fluid reservoir.    
REFER TO MAINTENANCE     AP42.10-P-4210D
INSTALLING Install     
22 Screw on cap of brake fluid expansion reservoir.    
23 Install cover above brake fluid expansion reservoir.    
24 Install heat shield for firewall. Model 118, 177, 247 with engine 260
Model 118, 177, 247 with engine 282
Model 118, 177, 247 with engine 654
Model 247 with engine 608		  
    Model 247 with engine 608 AR49.10-P-0001MFE
    Model 118, 177, 247 with engine 282 AR49.10-P-0001MFD
    Model 118, 177, 247 with engine 260 AR49.10-P-0001MFC
    Model 118, 177, 247 with engine 654 AR49.10-P-0001MFF
25 Install left front wheel and tire assembly.   AR40.10-P-1102MFA
CHECK VALUES FOR PNEUMATIC BRAKE BOOSTER

Number Designation Model 177.### 1# with engine 654 with code 411 with code B01, model 177.### 1# with engine 654 with code M013 except code 950/U29, model 177.### 2# with engine 260/608, model 177.### 2# with engine 282 except code ME08 Model 177 with engine 282 with code ME08, model 177.### 1# with engine 139/260, model 177.### 1# with engine 654 with code 950/U29, model 177.### 1# with engine 654 with codeB01 except code 411
BE43.10-P-1004-01H Brake line pressure Vacuum 0.92...0.98 bar Force on brake pedal (force to input rod for pedal -i = 3.3) 165 N bar 18 21
330 N bar 43 44
495 N bar 67 68
660 N bar 92 91
825 N bar 111 113
CHECK VALUES FOR PNEUMATIC BRAKE BOOSTER

Number Designation Model 177.### 1# with engine 282 except code ME08, model 177.### 1# with engine 608 model 177.### 2# with engine 139/654
BE43.10-P-1004-01H Brake line pressure Vacuum 0.92...0.98 bar Force on brake pedal (force to input rod for pedal -i = 3.3) 165 N bar 21
330 N bar 44
495 N bar 68
660 N bar 91
825 N bar 113
CHECK VALUES FOR PNEUMATIC BRAKE BOOSTER

Number Designation Model 247.### 1# with engine 282 except code ME08, model 247.### 1# with engine 608, model 247.0## 1# with engine 654 except code U29 (18 inch brake system) Model 247.### 1# with engine 260T model 247.### 1# with engine 282 with code ME08, model 247.0## 1# with engine 654 with code U29 (18 inch brake system), model 247.6## 1# with engine 654
BE43.10-P-1004-01I Brake line pressure Vacuum 0.92...0.98 bar Force on brake pedal (force on input rod where pedal i = 3.3) 165 N bar 18 21
300 N bar 43 44
495 N bar 67 68
660 N bar 92 91
825 N bar 111 113
CHECK VALUES FOR PNEUMATIC BRAKE BOOSTER

Number Designation Model 247.### 2#
BE43.10-P-1004-01I Brake line pressure Vacuum 0.92...0.98 bar Force on brake pedal (force on input rod where pedal i = 3.3) 165 N bar 21
300 N bar 44
495 N bar 68
660 N bar 91
825 N bar 113
CHECK VALUES FOR PNEUMATIC BRAKE BOOSTER

Number Designation Model 118.### 1# with engine 139/260 model 118.### 1# with engine 282/608/654 with code 950/U29 Model 118.### 1#
with engine 282/608/654 except code 950/U29
BE43.10-P-1004-01J Brake line pressure Vacuum 0.92...0.98 bar Force on brake pedal (force on input rod where pedal i = 3.3) 165 N bar 21 18
300 N bar 44 43
495 N bar 68 67
660 N bar 91 92
825 N bar 113 111
CHECK VALUES FOR PNEUMATIC BRAKE BOOSTER

Number Designation Model 118.### 2#
BE43.10-P-1004-01J Brake line pressure Vacuum 0.92...0.98 bar Force on brake pedal (force on input rod where pedal i = 3.3) 165 N bar 21
300 N bar 44
495 N bar 68
660 N bar 91
825 N bar 113
FRONT AXLE BRAKE CALIPER

Number Designation Model 118 Model 177
BA42.10-P-1004-10ZA Bleed screw at brake caliper M10 Nm 18 18
FRONT AXLE BRAKE CALIPER

Number Designation Model 247
BA42.10-P-1004-10ZA Bleed screw at brake caliper M10 Nm 18
Fig 1: Identifying Hand Pump (210 589 00 71 00)
G13657408Courtesy of MERCEDES-BENZ USA
Fig 2: Identifying Pedal Arrester (000 589 48 31 00)
G14790902Courtesy of MERCEDES-BENZ USA
Fig 3: Identifying Adapter For Brake Pedal Winch (211 589 00 31 00)
G16049313Courtesy of MERCEDES-BENZ USA
Fig 4: Identifying Test Connection (168 589 08 63 00)
G12939475Courtesy of MERCEDES-BENZ USA
Fig 5: Identifying Tester (201 589 14 21 00)
G14791030Courtesy of MERCEDES-BENZ USA
REPAIR MATERIALS

Number Designation Order number
BR00.45-Z-1028-04A Assembly cleaner A 000 986 56 01
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