12 13 ... Additional Fault Notes For Troubleshooting

Use the primary voltage test adapter, Special Tool 12 7 020, to troubleshoot the primary side of a separate ignition coil.

Fig 1: Identifying Primary Voltage Tester

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NOTE: If terminal 1 signal is not present on pin 1 in the diagnosis connector, the external trigger signal for the BMW Service Tester can be prepared with the help of Special Tool 12 7 020.

Connect BMW SERVICE TESTER.

Select Engine Test Step 05.

Enter number of cylinders (four).

Connect universal adapter to tester.

Connect brown clip to vehicle earth.

Connect black clip to terminal 1 of Special Tool 12 7 020.

NOTE: If trigger signal is missing from diagnosis box on 6-cylinder engine, preselect two cylinder settings on BMW SERVICE TESTER.

The red inductive clip is not used as only the cylinder is being tested. For this reason, the engine speed display will be too low by factor 4.

Connect Special Tool 12 7 020 to the ignition coil being tested and the vehicle wiring harness.

Produce a stationary signal on the oscilloscope by pressing key R.

Fig 2: Identifying Spark Line

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NOTE: The sparking voltage line on the oscilloscope will be very nervous, as the fuel/air mixture swirl of a 4-valve engine will be greater than that of a 2-valve engine.