Preparation for Test 1. Disconnect all vacuum lines at vacuum distributor block. 2. Check gray vacuum line to intake manifold for leaks. Permissible leakage of the elements with vacuum lines at 400 mbar vacuum per minute is 30 mbar.

Test equipment; See MBUSA Standard Service Equipment Program

Description	Brand, model, etc.
Connector	124 805 04 44

A. Vacuum Distributor Block, Vacuum Reservoir, Switchover Valve Block (Y11) Test

	Test scope	Test connection	Test condition	Nominal value	Possible cause/Remedy
1.0	Vacuum line to intake manifold	Vacuum tester to medium green line on switchover valve (Y11). Apply plug to gray line on intake manifold.	Be aware of check valve in vacuum line. Evacuate system with 300 mbar vacuum.	30 mbar pressure increase in 1 minute.	Vacuum lines.
2.0	Vacuum reservoir	Connect vacuum tester after connector (35) (passenger compartment).	Evacuate system with 300 mbar vacuum.	30 mbar pressure increase in 1 minute.	Vacuum lines, Vacuum reservoir.

B. Vacuum system test A 1. Left display : vacuum actuators 37, 38, 47 and 48 (medium green and red vacuum lines) with vacuum applied. 2. Left display and : vacuum actuator 41 (medium green vacuum line) with vacuum applied. 3. If vacuum on guage drops: remove lines from valve block (Y11) and then individually test lines and vacuum actuators. 4. Replace any defective vacuum actuator(s) or pneumatic line(s).

B. Vacuum system test B 1. Left display and : vacuum actuators 42 and 43 (red vacuum line). In addition: vacuum actuators 37 and 38 (see vacuum diagram 1, 32 /6). 2. If vacuum on guage drops: remove lines with support from valve block (Y11) and then individually test lines and vacuum actuators. 3. Replace any defective vacuum actuator(s) or pneumatic line(s). Vacuum diagram 2

Vacuum diagram 1

B. Vacuum system test C 1. Left display and : vacuum actuators 44 (dark red and medium green vacuum lines). In addition vacuum actuators 42 and 43 (see vacuum diagram 2, 32 /8). 2. If vacuum on guage drops: remove lines from valve block (Y11) and then individually test lines and vacuum actuators. 3. Replace any defective vacuum actuator(s) or pneumatic line(s).

Vacuum diagram 2