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Test 6: MOTRONIC Control Unit

  1. Check power supply. Turn on ignition. Connections 18 and 35 of control unit have approximately 12 volts. Connections 5, 16, 17 and 19 are connected to ground.
  2. Pull off relay 2 and bridge terminals No. 87 and 30. This will supply voltage to control unit. If necessary, check activation or replace relay 2. Turn on ignition and check voltage (12 volts) on terminals No. 85 and 86.
  3. In order to ensure that source of defect is only in control unit, it is recommended to replace DME unit (Motronic Control Unit) for comparison. In addition, perform various L-Jetronic test using BMW service test unit first, depending on type of complaint.
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