Checking Check Valve - AR43.10-P-0023V

Model 171, 172, 217, 222, 231 

Shown on model 171 

Courtesy of MERCEDES-BENZ USA

	Check
1	Eliminate vacuum in BAS brake booster (A7/7)	To do this, press the brake pedal several times with the engine switched off.
2	Open engine hood and raise to vertical position	Model 171, 172, 217, 222, 231
		Model 171, 172	AR88.40-P-1000V
3	Connect vacuum tester (030) with test connection (031) to BAS brake booster (A77)		AR43.10-P-0024-01V
		Tester	Fig 2
		Test connection	Fig 1
4	Start the engine and produce a vacuum of 0.75 to 0.8 bar by pressing and suddenly releasing the accelerator pedal	Reduce vacuum >0.8 bar by depressing the brake pedal.
5	Check the check valve (17)	For this, switch off engine. The vacuum must not reduce by more than 0.2 bar within 30 seconds. With vacuum loss > 0.2 bar ↓ Replace vacuum line (8) with check valve (17).
		Model 217 with engine 157, 278	AR43.10-P-0355LC
		Model 222.057/157 with engine 276.9	AR43.10-P-0355LFH
		Model 222 with engine 642	AR43.10-P-0355LFD
		Model 222 with engine 278	AR43.10-P-0355LFB
		Model 222 with engine 276.8	AR43.10-P-0355LF
		Model 171 with engine 271	AR43.10-P-0355V
		Model 171 with engine 113, 272	AR43.10-P-0355VA
		Model 172	AR43.10-P-0355W
		Model 231	AR43.10-P-0355RK
		If necessary: ↓ Checking brake booster
			AR43.10-P-0325V
6	Detach vacuum tester (030) with test connection (031) from BAS brake booster (A77)

Fig 1: Identifying Test Connection (168 589 08 63 00)

Courtesy of MERCEDES-BENZ USA

Fig 2: Identifying Tester (201 589 14 21 00)

Courtesy of MERCEDES-BENZ USA