Test brake system with pressure tester for leaks - AR42.10-P-0015CW

WARNING: This page is about a different car, the 2011 Mercedes-Benz C300, 2010 Mercedes-Benz C300, 2009 Mercedes-Benz C300, and 2008 Mercedes-Benz C300. However, it is still accessible from the selected car via links, so may be relevant.

MODEL 172, 204

Shown on model 204.0

Fig 1: Testing Brake System For Leaks

Courtesy of MERCEDES-BENZ USA

	Checking
	Risk of poisoning caused by swallowing brake fluid. Risk of injury caused by brake fluid coming into contact with skin and eyes.	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
	Brake fluid notes		AH42.50-P-0001-01A
	Notes on externally invisible brake fluid loss		AH42.10-P-9406-02V
	Notes on repairs to brake system		AH42.00-P-0003-01A
1	Deactivate easy entry and exit feature for steering wheel	Model 204 with code (275) Memory package (driver seat, steering column, mirrors)
2	Open engine hood and move to vertical position	Model 204
3	Clean area surrounding cap on brake fluid expansion reservoir (1)
4	Unscrew cap (1) on brake fluid expansion reservoir (2)
5	Connect brake fluid changer to brake fluid expansion reservoir (1)	Pay attention to manufacturer's operating instructions.
6	Remove bleed screw at the left front brake caliper (2) and connect pressure tester (3)	Pressure testers (3) for hydraulic oil systems must not be used for systems with brake fluid otherwise the brake fluid is mixed with mineral oil which can lead to brake failure. Pay attention to manufacturer's operating instructions. Measurement errors resulting form incorrect operation will otherwise occur.
7	Bleed pressure tester (3)
8	Switch off brake fluid changer and release pressure
	High-pressure check
	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 the engine as it is running	Secure vehicle to prevent it from moving by itself. Wear closed and snug-fitting work clothes. Do not touch hot or rotating parts.	AS00.00-Z-0005-01A
9	Allow the engine to run at moderate speed and release the accelerator pedal suddenly	To create the strongest vacuum in the BAS brake booster (A7/7).
10	Immediately press down brake pedal as far as possible and insert brake pedal jack (010) with adapter between brake pedal and seat	Cover the brake pedal and driver seat where they come into contact with the brake pedal jack and adapter. The brake pedal and driver seat can otherwise be damaged.
		Adapter for brake pedal winch	Fig 3
		Brake pedal winch	Fig 2
11	Read off and note brake pressure on high-pressure gauge of pressure tester (3)
12	Read off and note brake pressure again after 5 minutes on the high-pressure gauge of the pressure tester (3)	During the 5 min duration of the test, the brake pressure may not drop more than 5 %.
	Low-pressure testing
13	Switch off engine and remove brake pedal jack (010) with adapter
14	Push down brake pedal several times	In order to eliminate the vacuum in the brake booster (A7/7).
15	Depress brake pedal as far as possible and insert brake pedal jack (010) with adapter between brake pedal and driver seat	Cover the brake pedal and driver seat where they come into contact with the brake pedal jack and adapter. The brake pedal and driver seat can otherwise be damaged.
		Adapter for brake pedal winch	Fig 3
		Brake pedal winch	Fig 2
16	Slowly turn back brake pedal jack (010) until the low-pressure gauge on the pressure tester (3) displays a brake pressure of approx. 3 bar
17	Read off and note the brake pressure after 2 minutes on the low pressure gauge of the pressure tester (3)	The brake pressure must not drop during the 2 min duration of the test.
18	Remove brake pedal jack (010) and adapter
19	Disconnect pressure tester (3) from brake caliper (2) and screw bleed screw all the way into brake caliper (2)
20	Bleed brake system	Model 204	AR42.10-P-0010-02CW
		Rear axle	*BA42.10-P-1002-12J
		Front axle	*BA42.10-P-1003-10J
		Vehicle with manual transmission	*BA25.20-P-1001-01B
21	Disconnect brake fluid changer from brake fluid expansion reservoir (1)	Pay attention to manufacturer's operating instructions.
22	Check fluid level in brake system; correct if necessary	Model 204	AP42.10-P-4210CW
23	Screw cap firmly onto brake fluid expansion reservoir(1)
24	Close engine hood	Model 204
25	Activate easy entry and exit feature for steering wheel	Model 204 with code (275) Memory package (driver seat, steering column, mirrors)

FRONT AXLE BRAKE CALIPER

Number	Designation		Model 204 except model 204.077/277/377/9
BA42.10-P-1003-10J	Bleed screw to brake caliper	Nm	14

REAR AXLE BRAKE CALIPER

Number	Designation		Model 204 except model 204.077/277/377
BA42.10-P-1002-12J	Bleed screw to brake caliper	Nm	14

CLUTCH OPERATING MECHANISM

Number	Designation		Transmission 716.6
BA25.20-P-1001-01B	Bleed screw to central clutch operator	Nm	9

Fig 2: Identifying Brake Pedal Jack (000 589 18 31 00)

Courtesy of MERCEDES-BENZ USA

Fig 3: Identifying Adapter For Brake Pedal Jack (211 589 00 31 00)

Courtesy of MERCEDES-BENZ USA