(Checking Brake Booster - AR43.10-P-0325GG)

Model 460, 461

Model 463

up to model year 2013

except code 979 (Special protection MB Guard)

MODIFICATION NOTES

04.01.2002

Introduction of Brake Assist System (BAS) 30.09.01

Step 4

Courtesy of MERCEDES-BENZ USA

	Check
1	Connect vacuum tester (030) to brake booster		AR43.10-P-0024-01GG
	Measurement connection for checking non-return valve or brake booster	Only valid up to delivery date 31.12.1997.	WF58.50-P-4310-01A
		Vacuum tester	Fig 1
2	Connect pressure tester (051) to test connections. 000 588 07 21 00 Test equipment	On vehicles without test connections, connect the pressure tester (051) with the connection fitting to the brake caliper.	WS42.00-P-0014B
		Model 460, 461 Model 463 (except 463.270/271) up to model year 2013 except code 979 (Special protection MB Guard) Bleed screw at front axle fixed brake caliper	*BA42.10-P-1001-02B
		Model 463.270/271 up to model year 2013 except code 979 (Special protection MB Guard) Bleed screw to front axle floating brake caliper	*BA42.10-P-1001-03G
3	Attach pedal force meter (060) to brake pedal. 000 588 05 21 00 Roller brake test stand		WS42.00-P-0006B
4	Start engine and by opening the throttle produce a vacuum of 0.6 to 0.8 bar.	If only a substantially lower vacuum is attained, or if the vacuum immediately falls away, the O-ring between the brake booster and the tandem master brake cylinder may be damaged or the check valve in the vacuum line may be defective. Brake line pressure Brake line pressure The vacuum lines for the differential locks and vacuum reservoir may also be leaky. ↓ On vehicles with diesel engine, check vacuum pump. If air flow noises are audible at the brake booster: ↓ Install new sealing ring of diaphragm travel sensor.	*BE43.10-P-1003-01B
5	Apply specified force to the brake pedal and read line pressure	Brake line pressure Brake line pressure	*BE43.10-P-1003-01B
6	Detach pedal force meter (060) from brake pedal.
7	Disconnect pressure tester (051) from test connections	On vehicles without test connections, disconnect the pressure tester (051) with the connection fitting from the brake caliper.
8	Disconnect vacuum tester (030) from brake booster
9	Bleed brake system	Model 460, 461	AR42.10-P-0010GG
		Model 463.270/271 up to model year 2013 except code 979 (Special protection MB Guard) Only vehicles without test connections. Only bleed the brake caliper to which the pressure tester was connected.	AR42.10-P-0010GX

CHECK VALUES FOR PNEUMATIC BRAKE BOOSTER

Number	Designation					Model 460, 461	Model 463 up to model year 2019
BE43.10-P-1003-01B	Brake line pressure	Intake manifold vacuum 0.6-0.8 bar	Force on brake pedal	50 N	bar	11...21	11...21
				100 N	bar	35...45	35...45
				150 N	bar	53...63	53...63
				200 N	bar	81...90	81...90
				250 N	bar	98...120	98...120

CHECK VALUES FOR PNEUMATIC BRAKE BOOSTER

Number	Designation					Model 463 as of model year 2019
BE43.10-P-1003-01B	Brake line pressure	Intake manifold vacuum 0.6-0.8 bar	Force on brake pedal	50 N	bar	-
				100 N	bar	-
				150 N	bar	-
				200 N	bar	-
				250 N	bar	-

FRONT AXLE FIXED BRAKE CALIPER

Number	Designation		Model 460	Model 461 (except 461.339) Model 463 up to model year 2019
BA42.10-P-1001-02B	Bleed screw at front axle fixed brake caliper	Nm	14	14

FRONT AXLE FIXED BRAKE CALIPER

Number	Designation		Model 461.339 with code ZD4 (Vehicle for non-civilian operations)
BA42.10-P-1001-02B	Bleed screw at front axle fixed brake caliper	Nm	14

FRONT AXLE FLOATING BRAKE CALIPER

Number	Designation		Model 463.270/271
BA42.10-P-1001-03G	Bleed screw to front axle floating brake caliper	Nm	17

Fig 1: Identifying Vacuum Tester (201 589 13 21 00)

Courtesy of MERCEDES-BENZ USA