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Retrieving Codes: 5-Cylinder

  1. Turn ignition off. Perform pretest conditions. See PRETEST CONDITIONS  . Connect Pulse Counter (124 589 19 21 00) to vehicle battery and diagnostic connector located in right rear corner of engine compartment. See Fig 1 .
  2. U-BATT LED on pulse counter display will illuminate if equipment is properly connected. If U-BATT LED illuminates, go to step 5). If U-BATT LED does not illuminate, check pulse counter fuse. Replace as necessary. If pulse counter fuse is okay, go to next step.
  3. Using a DVOM, measure voltage between diagnostic connector terminal No. 1 and battery positive terminal. Voltage should be 11-14 volts. If voltage is not 11-14 volts, repair wiring as necessary or replace vehicle battery.
  4. Using a DVOM, measure voltage between diagnostic connector terminals No. 1 and 4. Voltage should be 6-12 volts. If voltage is not 6-12 volts, repair wiring as necessary or replace vehicle battery.
    Fig 1: Retrieving Codes (5-Cylinder)
    G93E79172Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
  5. Start engine and idle. Press START button on pulse counter for 2-4 seconds maximum. Pressing push button longer than 2-4 seconds will erase code in memory. Read pulse output on pulse counter. If pulse counter displays "1", no faults are stored. If pulse counter displays a number greater than "1", faults are stored.
  6. Press START button again for 2-4 seconds. If more fault codes are stored, pulse counter will display next code. Continue pressing START button for 2-4 seconds at a time until pulse counter displays first fault again. Record all fault codes. See FAULT CODE DEFINITION  .
  7. If no fault codes are displayed on pulse counter and driveability or customer complaints are present, perform functional test on ELR, EGR, and P-2 control. See 5-CYLINDER FUNCTIONAL TEST CHARTS  under FUNCTIONAL TESTS.