BMW X5: Ignition Coil

NOTES ON CHECKING IGNITION SYSTEM

Troubleshooting

• Fault in fuel injection system
• Spark plug faults
• Ignition coil faults
• Further fault patterns with evaluation
• Additional fault notes for troubleshooting

Oscillograms

• Normal oscillogram
• Oscillograms of ignition coils from different manufacturers

Check

• Secondary signal for stationary ignition distribution

ADDITIONAL FAULT NOTES FOR TROUBLESHOOTING

Necessary preliminary tasks:

• Connect diagnosis system

Fig. 5: Identifying Diagnosis Information System

CHECKING SECONDARY SIGNAL FOR STATIONARY IGNITION DISTRIBUTION

Special tools required:

• 12 7 030

Remove ignition coil. Clip special tool 12 7 030 on relevant ignition coil to be tested. Clip high tension clip around ignition lead.

Fig. 6: Removing Ignition Coil

Connect earth lead of adapter to vehicle earth and ignition coil. Connect up diagnosis connector.

If trigger signal is not present (terminal 1), connect black clip of universal adapter cable to pin 1 of primary adapter cable.

Fig. 7: Connecting Earth Lead Of Adapter To Vehicle Earth And Ignition Coil

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

NOTE: Neighboring ignition leads could produce interference on the screen of the oscilloscope.

Interrogate fault memory and its fault reports.

Fig. 8: Identifying Waveform

FURTHER FAULT PATTERNS WITH EVALUATION

Necessary preliminary tasks:

• Connect diagnosis system

Fig. 9: Identifying Diagnosis And Information System

CHECKING ROD-TYPE IGNITION COILS (M54, M56, N40, N42, N43, N45, N46, N52, N62, N62TU, N73)

Special tools required:

• 12 1 301
• 12 7 050

Necessary preliminary tasks:

• Read out fault memory in DME (Digital Engine Electronics)
• N40: Remove sound absorption hood
• N42: Remove sound absorption hood
• N43: Remove sound absorption hood
• N45: Remove sound absorption hood
• N46: Remove sound absorption hood
• N52: Remove sound absorption hood
• N62/N62TU: Remove sound absorption hood
• N62/N62TU: Remove ignition coil cover Open control unit box
• Remove M54/56 ignition coil cover

Unlock plug fastener (1) of ignition coil.

Fig. 10: Unlocking Plug Fastener Of Ignition Coil

Detach plug (1) in direction of arrow.

Pull out ignition coil (2) towards top.

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

Fig. 11: Detaching Ignition Coil Connector

Install special tool 12 7 050.

Installation:

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

Fig. 12: Identifying Special Tool 12 7 050

Secondary measurement:

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

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.

Fig. 13: Identifying KV Clip-On Probe

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.

Procedure on DIS Tester:

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

For subsequent procedure, follow DIS instructions.

IMPORTANT: Ignition signal is a multiple spark ignition.

Fig. 14: Identifying Connector

Illustration of multiple spark ignition

1. Start of ignition peak.
2. Level of ignition voltage.
3. Level of sparking voltage.
4. Spark duration.
5. Sparking voltage curve.
6. Start of decay process.
7. Decay process.

Fig. 15: Multiple Spark Ignition Graph

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:

Depending on engine temperature (approx. -20º to 100º) 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.

Fig. 16: Identifying Waveform Of Ignition Peak

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

Differences of 3000 to 4000 volts are permitted.

REPLACING IGNITION COIL (N62TU)

Necessary preliminary tasks:

• Switch off ignition
• Remove INTAKE FILTER HOUSING

Release screws and remove holder (1).

Pull ignition coil covers (2) out of rubber grommets.

Fig. 17: Locating Holder And Screws

Unlock plug fastener (1) of ignition coil.

Fig. 18: Unlocking Plug Fastener Of Ignition Coil

Detach ignition coil connector in direction of arrow.

Pull out ignition coil (2).

This procedure is applicable to all ignition coils.

Fig. 19: Detaching Ignition Coil Connector

Installation:

Insert rubber seal on ignition coils (2) between guides.

Fig. 20: Inserting Rubber Seal On Ignition Coils Between Guides

Assemble engine.

NOTE: Read out DME fault memory.

Check function of DME.

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