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Impulse Counter Readout

Code retrieval is accomplished through use of Impulse Counter (124 589 19 21 00) connected to diagnostic connector. Impulse counter leads connect to diagnostic connector pins No. 1 and 4 and Red wire connects to battery voltage. Connect tester according to diagram. See Fig 1 . U-BAT LED on impulse counter display will illuminate if impulse counter is properly connected. If display does not illuminate, check impulse counter fuse, and measure voltage at diagnostic connector pin socket No. 1. Voltage should be 11-14 volts.

Fig 1: Connecting Testers (300D, 350SD & 350SDL)
G91D17460Courtesy of MERCEDES-BENZ OF NORTH AMERICA