LEMON Manuals: Even more car manuals for everyone
Home >> Mercedes Benz >> 1984 >> 300SD >> Repair and Diagnosis >> Engine Performance >> System >> EGR System - Diesel >> Testing >> CALIFORNIA Turbo Diesel >> Vacuum Converter

Vacuum Converter

With engine off, ignition switched on. Pull plug from vacuum converter and connect to volt/ohmmeter and read voltage. If reading is 12 volts, vacuum converter is OK. If voltage is not 12 volts, check excess voltage protection and electric activation.



  1. Connect vacuum tester with vacuum line to connecter 2 of vacuum converter. With engine at idle, read vacuum value. Reading should be no more than 12 in. Hg vacuum. If test is OK, go to step 2). If test is not OK, test vacuum lines and vacuum pump.
  2. Connect vacuum tester (116 589 25 21 00) with "Y" fitting to connector 1. Connect volt/ohmmeter with test cable (102 589 04 63 00) to vacuum converter. Reading ohms, test vacuum converter at the following speeds: At 700-2600 approx. 7.5-10.0 in. Hg vacuum with 530 mA. At 2600-3000 RPM, vacuum should drop approx. 2.0 in. Hg vacuum with 370 mA. If test is OK, end of test. If test is not OK, go to step 3).
  3. If the current values are OK, but vacuum is not OK, Replace vacuum converter. If vacuum is OK, but current values are not OK, Perform activation test and replace ECU if necessary.
scientia non olet · About LEMON Manuals