12 13 009 Checking ignition pencil coils with scan tool or oscilloscope

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2006 BMW X5, 2006 BMW X3, 2005 BMW X5, 2005 BMW X3, and 2004 BMW X5. However, it is still accessible from the selected car via links, so may be relevant.

Special tools required:

12 1 301
12 7 050

Necessary preliminary tasks:

Read out fault memory in DME (Digital Motor Electronics)
Remove ignition coil cover

Unlock plug fastener (1) of ignition coil.

Fig 1: Unlocking Plug Fastener Of Ignition Coil

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Detach plug (1) in direction of arrow.

Fig 2: Pulling Out Ignition Coil

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Pull out ignition coil (2) towards top.

NOTE: Procedure applies to all rod-type ignition coils.

Install special tool 12 7 050.

Fig 3: Identifying Special Tool

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Installation:

Special tool 12 7 050 is attached between spark plug and rod-type ignition coil.

Secondary measurement:

Connect KV clip-on probe (1) of DIS Tester to special tool 12 7 050.

Fig 4: Connecting KV Clip-On Probe

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Procedure on DIS Tester:

Select < Measurement >.
Select < Preset measurement >.
Select < Secondary ignition signal >.
Connect < TD cable to diagnostic head >.
Select < static ignition distribution >.
Select < Number of cylinders >.

For subsequent procedure, follow DIS instructions.

NOTE: Illustration shows: KV clip-on probe (1) US version.

Primary measurement:

Connect 26-pin pin box with special tool 12 1 301 to connector (1) DME module 5.

Fig 5: Connecting 26-Pin Pin Box

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Procedure on DIS Tester:

Select < Measurement >.
Select < Preset measurement >.
Select < Ignition signal term.1 >.

For subsequent procedure, follow DIS instructions.

NOTE: Pin assignment according to connection scheme. Illustration N42.

IMPORTANT: Ignition signal is a multiple spark ignition.

Illustration of multiple spark ignition

Start of ignition peak.
Level of ignition voltage.
Level of sparking voltage.
Spark duration.
Sparking voltage curve.
Start of decay process.
Decay process.

Fig 6: View Of Ignition Signal
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M54 / M56 / N40 / N42 / N45 / N46 / N62 / N73:

The following ignition oscillogram applies to engines with multiple spark ignition from a production date of April 2001:

Fig 7: View Of Ignition Peak On Oscillogram

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Depending on engine temperature (approx. -20° to 100°) and engine speed (< 2000 RPM, some ignition voltage peaks (approx. 1-5 ignition peaks) can occur before the typical ignition voltage characteristic.

The additional ignition peaks play no role in diagnosis.

The last ignition peak (1) on the oscillogram is decisive.

NOTE: The display of the ignition voltage peak is approx. 20-25 % lower than the real value.

It is not the height of the ignition voltage peaks but rather the uniformity of all the cylinders that is important.

Differences of 3000 to 4000 volts are permitted.