300SD (140.134) L6-3.5L DSL Turbo (603.971) (1993)
CHECKING VALVE BLOCK (Y11):
1. Ignition switched off.
2. Connect grey-green vacuum line to tester.
3. Evacuate with tester and read off pressure gauge. If a pressure increase occurs on the pressure gauge, renew valve block (Y11) or grey-green
vacuum line.
NOTE: If no fault was found on the above test, the vacuum elements of the automatic climate control (KLA) are to be checked.