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Engine Electrical System - Repair (n52) BMW Z4 E89

Gauges & Instrument Panels 81 illustrations ~4869 words

61 20... Battery replacement information

A vehicle battery is constructed for the installation location and the individual power requirements of the particular vehicle. These individual power requirements depend on the motorization and different types of optional equipment. The individually assigned vehicle battery is the ideal compromise between the power requirements of the vehicle electrical system and the weight and service life of the vehicle battery.

Vehicles with the automatic engine start-stop function or particular motorization and optional equipment are equipped with a special vehicle battery (AGM battery), since only this battery type can provide elevated power requirements over the extended service life. Installing a different vehicle battery can cause problems with vehicle electronics, can reduce functions or can cause leakage of battery acid.

In the event of an accident where the airbags are deployed in vehicles with a vehicle battery in the luggage compartment, the electrical connection between the vehicle battery and the trigger is automatically disconnected through pyrotechnics. This prevents a possible short circuit.

Proper operation of all of these safety and convenience functions requires a battery that conforms with specifications and that is properly registered in vehicles with energy management systems (IBS, power module).

Vehicles with energy management systems (IBS, power module): Register battery replacement

The vehicle electrical system is informed about the vehicle battery characteristic data, such as type, size, age and current power capacity. Therefore, only one work scope will be provided that is permitted by the current status of information.

When installing a new vehicle battery, the battery must be registered and thus must also be registered with the vehicle electrical system.

Diagnosis system

Register battery replacement

  1. Service functions
  2. Body
  3. Voltage supply
  4. Register battery replacement
  5. Test plan

When retrofitting, a more powerful battery may be used. Standard batteries may always be replaced by AGM batteries with the same specifications.

When installing a battery of a different size or a different battery type, this change in vehicle data must be programmed into the vehicle data in accordance with specifications.

Programming system

  1. Battery retrofitting

61 13... Butt connector for repairing a plug connection

IMPORTANTIdentify cause of damage (e.g. sharp-edged body parts, faulty electrical loads, jammed mechanisms, corrosion caused by ingress of water, etc.). Read out fault memory Eliminate cause of damage. Disconnect battery negative terminal Make sure that no safety-related system according to circuit diagram (e.g. antilock braking system, active rear-axle kinematics, airbags, etc.) are influenced. Otherwise replace faulty wiring harness or use repair cable (sourcing reference: BMW Parts Service) Carry out function test and read out fault memories again Eliminate new faults if applicable and clear fault memories

Note. The repair range IV for vehicle electrical system contained the required special tools and individual parts for retrofitting and repair work with the aid of fan connectors. The case can no longer be ordered.

Scheme 95

Scheme 95

Choose repair kit.

Example: Repair kit, circular plug system D 2.5.

Scheme 96

Scheme 96

Remove following parts

  1. Pre-packaged end of cable with requisite wire cross-section
  2. Crimp connector for selected wire cross-section
  3. Shrink-fit hose

Scheme 97

Scheme 97

Open secondary lock on housing.

Mark damaged contact (4) with socket number of housing and press it out of housing using appropriate special tool contained in special tool kit 61 0 300.

See repair instructions

INSTRUCTIONS FOR OPENING CONTACTS AND LOCKS of different plug contact systems.

Scheme 98

Scheme 98
IMPORTANTCheck maximum length of repair cable If more than one wire is to be repaired, the individual interfaces must be offset so that the wiring harness is not too thick at the repaired point.

Adhere to following procedure

  1. Cut off wire with faulty contact at point which is easily accessible
  2. Strip insulation from end of wire at wiring harness end
  3. Cut preassembled wire end to length and strip insulation

Refer also to repair instruction

Scheme 99

Scheme 99

Crimp butt connector on preassembled wire end.

Special tools

  1. 61 4 328 (0.35 - 2.5 mm 2
  2. 61 0 240 (4.0 - 6.0 mm 2

See repair instructions

Scheme 100

Scheme 100

Push shrink-fit hose (8) onto free wire end.

Scheme 101

Scheme 101

Crimp unused wire end to butt connector.

Scheme 102

Scheme 102

Pull shrink-on sleeve over butt connector.

Scheme 103

Scheme 103
IMPORTANTDo not burn shrink-on sleeve.

With hot air blower, shrink the shrink-on sleeve on both sides (9) of shrink-fit hose until glue emerges uniformly all round.

Insert contact in housing.

Close secondary lock on housing.

Scheme 104

Scheme 104

12 00 Contents of Engine Electrical System General

General Information

  1. «WORKING ON IGNITION SYSTEM»(/bmw/z4/e89-2009-2013/remont/gauges-instrument-panels/#engine-electrical-system-repair-n52__12-00-instructions-for-working-on)
  2. «REMOVING AND INSTALLING ELECTRONIC CONTROL UNITS»(/bmw/z4/e89-2009-2013/remont/gauges-instrument-panels/#engine-electrical-system-repair-n52__12-00-notesinformation-on-removing-and)
  3. Welding work (overload protection of control units)
  4. «Disconnecting and connecting battery»(/bmw/z4/e89-2009-2013/remont/gauges-instrument-panels/#engine-electrical-system-repair-n52__61-00-instructions-for-disconnecting-and)
  5. Disconnecting and connecting test equipment
  6. Component inspection
  7. «EXTERNAL JUMP-STARTING AID»(/bmw/z4/e89-2009-2013/remont/gauges-instrument-panels/#engine-electrical-system-repair-n52__12-00-notesinformation-on-start-assistance)
  8. Compression testing

61 00... Instructions for disconnecting and connecting battery

Before disconnecting battery

Turn off the ignition and other electrical loads/consumers to prevent sparking when reconnecting.

Note. If the ignition is not turned off when the battery is disconnected, fault memories may be set in some control units.

IMPORTANTThere is a danger of mixing up battery leads: If the battery positive and negative leads are the same color and you are in doubt, follow the polarity to the battery, then mark and cover the leads. The on-board computer and clock may lose your data.

General notes on disconnecting battery

  1. Do not disconnect battery leads and leads from alternator and starter motor while engine is running.
  2. Cars with IBS on battery negative terminal
  3. Disconnect terminal of «BATTERY NEGATIVE LEAD»(/bmw/z4/e89-2009-2013/remont/horns/#general-electrical-system-repair__61-20-900-disconnecting-and-connecting) from vehicle battery. Cover battery negative terminal(s) and secure.
  4. When work is carried out on the electrical system, faults may be caused in the fault memories of some control units when the battery is connected.
  5. When installing battery terminal: Tightening torque «61 21 1AZ»(/bmw/z4/e89-2009-2013/remont/horns/#general-electrical-system-tightening-torques) .

After connecting battery

IMPORTANTThe scope of application of some systems may be restricted after a power supply interruption. Likewise, individual settings may be lost. Settings or activations must be carried out, depending on the equipment specification. For example: If necessary, carry out adjustment of active steering If necessary, activate slide/tilt sunroof If necessary, activate POWER WINDOWS

61 13... Instructions for opening contacts and locks of different plug contact systems

Abbreviations of contacts and what they mean
ELAStrand seal
D 1.5/2.5/3.5Round contacts with 1.5 mm, 2.5 mm or 3.5 mm diameter
MDKMiniature double flat spring contact
JPTJunior Power timer
DFKDouble flat spring contacts
EloElectronic contacts
Elo PowerElectronic contacts for heavy load
MQSMicro Quadlock system
MPQMicro Power Quadlock
MLKMini laminated contact
SLKSensor laminated contact
LSKLoad current contact
MLKMini laminated contact
MconMulti contact

SPECIAL TOOL DESCRIPTION

IMPORTANTThe contacts can be changed on ultrasonically welded plugs (1). Ultrasonically welded plugs (1) must be replaced completely.

Ultrasonic-welded connectors (1) can be identified by the welds (2) on their longitudinal side.

Scheme 105

Scheme 105

Note. Special tools referred to in the repair instructions below are contained in the following special tool kits: Release and pressing-off tool61 1 150 will be replaced on 09/2005 by 61 0 300 (BMW) and 61 0 400 (MINI) Release and pressing-off tool 61 1 100 (engine)

12 00... Instructions for working on the ignition system

CAUTIONAlways switch off ignition before working on ignition system. Use only test leads which have been approved and belong to these testing instruments (e.g. DIS Tester). Comply with operating instructions of the respective testing instrument used. Comply with the country-specific safety regulations. Never touch components under current with engine running! Comply with instructions of DIS tester. Do not connect any suppression capacitors or inspection lamps to terminal 1 on the ignition coil. Terminal 1 of ignition coil must not be connected to ground or battery positive lead. If an alarm system is subsequently installed, lead of terminal 1 must not be used for start prevention. When working on ignition system, always disconnect supply leads to ignition coils. High tension! - High tension!
IMPORTANTHazardous voltages occur at
  1. Ignition lead
  2. spark-plug connectors
  3. spark plugs
  4. Ignition coil (high voltage at terminal 4 is approx. 40 kV)
  5. Lead of terminal 1 from ignition coil to DME control unit (high voltage approx. 350 V)

12 13 Notes on checking ignition system

Troubleshooting

  1. Fault in fuel injection system
  2. Spark plug faults
  3. Ignition coil faults
  4. Further fault patterns with evaluation

Oscillograms

  1. Normal oscillogram
  2. Oscillograms of ignition coils from different manufacturers

Check

  1. Secondary signal for stationary ignition distribution

61 00... Notes on handling wiring harnesses and cables

The following applies in general

To avoid damage, observe the following instructions

  1. Avoid compressive and tensile loads
  2. Make sure cables are laid without kinks or abrasions
  3. Ensure non-contacting routing at sharp-edged body components; use edge protection if necessary
  4. Secure additionally laid cables/lines with cable straps

The following additionally applies

Shielded lines

Contact points in the shield can cause problems with regard to noise radiation and interference immunity. Consequently, distinctions have to be drawn between the following types

Coaxial line

  1. Shielded RTK031 coaxial lines may only be repaired with special crimping tools.

CVBS lines

  1. CVBS lines may not be repaired.
  2. CVBS lines must be replaced in their entirety.

HSD lines

  1. HSD lines may not be repaired.
  2. HSD lines must be replaced in their entirety.

Optical fibre cable

Note. Optical fibre cables are colored differently as follows: Green = MOST (M edia O riented Systems T ransport) optical fibre Yellow = ISIS ( I ntelligent S afety I ntegration S ystem) optical fibre Orange = repair optical fibre cables

IMPORTANTOptical fibre cables are permitted to show only one separation point (bridge), replace optical fibre cables if necessary Smallest permissible bending radius is 25 mm Avoid influence of heat > or = 85 °

Treating cables and optical fibre cables

FlexRay

It is possible to repair the FlexRay. In the event of damage, the cables can be joined with conventional butt connectors.

Note. The line is a twisted cable. If possible, maintain twist in line after repair.

Airbag lines

Repairing airbag cables

Ribbon cables

Repairing ribbon cables Z

12 00... Notes/information on removing and installing control units

IMPORTANTDisconnecting the vehicle battery will cancel the fault memories of control units. Consequently, before disconnecting the car's battery, always interrogate the fault memories. Investigate stored faults and, once any faults have been remedied, cancel the fault memory. Control unit plugs should only ever be connected and disconnected while the ignition is turned off. The removal and installation of components, relays, fuses etc. can cause faults to be stored in fault memories capable of self diagnosis. Always interrogate the fault memories after completing work on the electrical system. Investigate stored faults and, once any faults have been remedied, cancel the fault memory. If necessary, initialize power window units When replacing the DME/DDE control unit, observe the following: In each case read out the hardware/software status of the relevant control unit using the BMW diagnosis system. Comply with the instructions of the DIS diagnosis system on the steps pertaining to coding and programming. On vehicles with electronic vehicle immobilization, comply with the instructions of the BMW diagnosis system. Each control unit is programmed with certain basic values, which serve as mean values. The control unit receives different input values, depending on engine condition, which are compared with the stored values. The adaptive system compares the input values with the stored map values. The control commands are routed to the relevant actuators. If the DME control unit is without current for a long time (more than one hour), its adaptive system loses the stored values. When a cleared control unit is restarted or a new control unit is installed, the adaptive system must read in and store the input values of the associated engine as new basic values itself. This procedure could lead to erratic idling and disturbed overrunning of the engine after starting. Depending on the engine it could require some time before all values are adapted to the engine condition. Therefore observe the following procedure before replacing or reinstalling a DME/DDE control unit: If possible before exchanging control unit, run engine up to operating temperature. Exchange control units and run the vehicle at alternating engine speeds.

12 00... Notes/information on start assistance (jump starting)

Do not start the engine with help of starting sprays.

Preparation

Conform with the following when starting the engine with a jump starting cable.

  1. Ensure that the jump starting cable wires are of appropriate cross-section size.
  2. Only use fuse-protected jump starting cables.
  3. Check whether the current-supplying battery has 12 V voltage.
  4. If the engine is started from the battery of another vehicle, ensure that there is no contact between the bodies of both vehicles.
IMPORTANTNever touch electrically live ignition system components: high voltage - danger of injury!

If the battery in the vehicle supplying power is weak, start the engine of this vehicle and let it run at idling speed.

Operation

It is essential to conform to the procedures so as to avoid injury to persons or damage to parts.

  1. Automatic transmission: select drive position "P", apply parking brake.
  2. Manual transmission: move gear lever to neutral position, apply parking brake.
  3. Ensure that the jump leads cannot get caught in rotating parts, e.g. fan.
  4. First connect both positive poles of the batteries with one jump starting cable (red).
  5. Use the battery positive terminal in the engine compartment for vehicles with the battery in the luggage compartment.
  6. Then use the second jump starting cable (black) to connect the negative post of the current-supplying battery with the earth/ground point (not the negative pole or the body) of the vehicle to be started.
IMPORTANTDo not connect the second jump starting cable (black) with the negative pole of the battery in the vehicle to be started. Produced gas could be ignited by sparks.

Risk of explosion!

After the engine of the vehicle to be started has fired, first disconnect the jump starting cable between the negative pole and the earth/ground point. Then remove the starting cable from the positive poles.

00 Safety information for working on vehicles with automatic engine start-stop function (MSA)

WARNINGIf the engine hood/bonnet contact is pulled upwards (workshop mode), the information "switch closed" is output. The automatic engine start-stop function is active. An automatic engine start is possible.

Observe safety precautions when working on MSA vehicles

Before carrying out practical work on the engine, always ensure that the MSA functionality is deactivated so as to prevent automatic engine starting while work is being carried out in the engine compartment.

MSA function is deactivated by

Scheme 106

Scheme 106
  1. Deactivate MSA by means of button (1) in passenger compartment
  2. Open seat belt buckle and driver's door
  3. Open engine bonnet/hood and ensure that engine hood/bonnet contact is not in workshop mode
  4. Workshop mode A = 10 mm
  5. Basic setting (engine hood/bonnet open) B = 7 mm

To make sure that the engine hood/bonnet contact is at the basic setting, if necessary press the hood/bonnet contact up to the limit position before starting work and slowly release.

Scheme 107

Scheme 107

When working with diagnosis tools

  1. Observe instructions in diagnosis tool

12 12 011 Replacing all spark plugs (N52K)

Necessary preliminary work

  1. Switch off ignition.
  2. Remove «IGNITION COILS»(/bmw/z4/e89-2009-2013/remont/gauges-instrument-panels/#engine-electrical-system-repair-n52__12-13-511-replacing-ignition-coils) .
IMPORTANTWear safety goggles. Oil and dirt particles may get into your eyes!

Clean spark connector slot with compressed air.

Unscrew spark plugs with special tool 12 1 171 and an extension with a joint.

Installation note

First, hand-thighten the spark plugs with special tool 12 1 171 and with an extension with a joint into the engine.

Then tighten the spark plugs using a torque wrench, special tool 12 1 171 and an extension with a joint.

Observe tightening torque.

Tightening torque 12 12 2AZ .

Scheme 108

Scheme 108

12 13 009 Checking rod-type ignition coils (M54, M56, N40, N42, N43, N45, N46, N52, N62, N62TU, N73)

Necessary preliminary tasks

  1. Read out fault memory in DME (Digital Engine Electronics)
  2. N52: Remove sound absorption hood

Unlock plug fastener (1) of ignition coil.

Scheme 109

Scheme 109

Detach plug (1) in direction of arrow.

Pull out ignition coil (2) towards top.

Note. Procedure applies to all rod-type ignition coils.

Scheme 110

Scheme 110

Install special tool 12 7 050 .

Installation

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

Scheme 111

Scheme 111

Secondary measurement

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

Procedure on DIS Tester

  1. Select .
  2. Select .
  3. Select .
  4. Connect .
  5. Select .
  6. Select .

For subsequent procedure, follow DIS instructions.

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

Scheme 112

Scheme 112

Primary measurement

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

Procedure on DIS Tester

  1. Select .
  2. Select .
  3. Select .

For subsequent procedure, follow DIS instructions.

Note. Pin assignment acc. to connection scheme. Illustration shows N42.

Scheme 113

Scheme 113
IMPORTANTIgnition signal is a multiple spark ignition.

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.

Scheme 114

Scheme 114

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. -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.

Scheme 115

Scheme 115

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.

Troubleshooting

  1. Fault in fuel injection system
  2. Spark plug faults
  3. Ignition coil faults
  4. Further fault patterns with evaluation

Oscillograms

  1. Normal oscillogram
  2. Oscillograms of ignition coils from different manufacturers

Check

  1. Secondary signal for stationary ignition distribution

12 13 511 Replacing ignition coils (N52K)

Necessary preliminary tasks

  1. Read out fault memory of DME control unit.
  2. Check stored fault messages
  3. Switch off ignition
  4. Remove «ACOUSTIC COVER»(/bmw/z4/e89-2009-2013/remont/oem-general-information/#maintenance-and-general-information-repair-n52__11-00-removing-and-installingreplacing-acoustic)
  5. Remove right «TENSION STRUT»(/bmw/z4/e89-2009-2013/remont/axle-shafts/#front-axle-repair__51-71-371-removing-and-installingreplacing)

Unlock plug fastener of ignition coil (1) and disconnect plug.

Pull ignition coil (1) up and out.

This procedure is applicable to all ignition coils.

Scheme 116

Scheme 116

Installation

Check that rubber seal of ignition coil (1) is correctly seated.

Scheme 117

Scheme 117

Installation

Push plug (1) with plug fastener (2) open onto ignition coil.

Carefully close plug fastener (2) in direction of arrow.

Scheme 118

Scheme 118

Installation

The plug fastener must snap into place without great effort.

Scheme 119

Scheme 119

Note. Now clear the fault memory.

12 14 700 Coding control module (DME/DDE)

Switch on ignition.

Connect MoDiC or DIS/GT1 Tester.

Select "Coding" program.

For subsequent procedure, follow instructions in MoDiC or DIS/GT1 Tester.

Carry out adjustment of following control units

  1. EWS (electronic immobilizer)
  2. DME (Digital Motor Electronics) or
  3. DDE (Digital Diesel Electronics)

12 14 705 Programming control unit (DME/DDE)

Switch on ignition.

Connect MoDiC or DIS/GT1 Tester.

Select "Programming".

For subsequent procedure, follow instructions in MoDiC or DIS/GT1 Tester.

Carry out adjustment of following control units

  1. EWS (electronic immobilizer)
  2. DME (Digital Motor Electronics) or
  3. DDE (Digital Diesel Electronics)

12 14 600 Removing/replacing knock sensors (N52K)

IMPORTANTAluminium-magnesium materials.

No steel screws/bolts may be used due to the threat of electrochemical corrosion.

A magnesium crankcase requires aluminum screws/bolts exclusively.

Aluminum screws/bolts must be replaced each time they are released.

Aluminum screws/bolts are permitted with and without color coding (blue).

For reliable identification

Aluminum screws/bolts are not magnetic.

Jointing torque and angle of rotation must be observed without fail (risk of damage).

Necessary preliminary tasks

  1. Read out fault memory of DME control unit
  2. Switch off ignition
  3. Remove «INTAKE AIR MANIFOLD»(/bmw/z4/e89-2009-2013/remont/mechanical/#engine-repair-n52__11-61-050-removing-and-installing)

Unlock plug (1) and remove.

Scheme 120

Scheme 120

Release screws on both knock sensors (1) and remove knock sensors (1).

Installation

Replace aluminum screws.

Tightening torque 13 62 3AZ .

Scheme 121

Scheme 121

Installation

Clean support face of knock sensors on engine block.

Scheme 122

Scheme 122

Note. Check stored fault messages. Now clear the fault memory.

12 14 550 Replacing control unit (DME) (N52K)

IMPORTANTRead and comply with notes on PROTECTION AGAINST ELECTROSTATIC DAMAGE (ESD PROTECTION)

Necessary preliminary tasks

  1. Turn off ignition
  2. Disconnect «BATTERY NEGATIVE LEAD»(/bmw/z4/e89-2009-2013/remont/horns/#general-electrical-system-repair__61-20-900-disconnecting-and-connecting)
IMPORTANTFollow instructions for REMOVING AND INSTALLING CONTROL UNITS

Replacement

  1. Carry out programming/encoding
IMPORTANTIt is absolutely essential to read out the fault memory with the BMW diagnosis system and to create a fault memory printout.

Switch off ignition.

Release bolts along line (1).

Tightening torque 12 90 1AZ .

Remove electronics box cover.

Scheme 123

Scheme 123

Unlock battery positive lead (1), detach and lay to one side.

Release locks (2) in direction of arrow and pull control unit upwards slightly.

Scheme 124

Scheme 124

Pull control unit (1) upwards slightly until plug (2) can be released from control unit in direction of arrow.

Unlock plug (2) and detach from control unit (1).

Scheme 125

Scheme 125

Lift out control unit (1).

Scheme 126

Scheme 126

Note. Check stored fault messages. clear fault memory.

12 14 521 Replacing crankshaft pulse generator (N52K)

IMPORTANTRead and comply with notes on PROTECTION AGAINST ELECTROSTATIC DAMAGE (ESD PROTECTION) .
IMPORTANTAluminium-magnesium materials.

No steel screws/bolts may be used due to the threat of electrochemical corrosion.

A magnesium crankcase requires aluminum screws/bolts exclusively.

Aluminum screws/bolts must be replaced each time they are released.

Aluminum screws/bolts are permitted with and without color coding (blue).

For reliable identification

Aluminum screws/bolts are not magnetic.

Jointing torque and angle of rotation must be observed without fail (risk of damage).

Necessary preliminary tasks

  1. Read out fault memory of DME control unit
  2. Switch off ignition

Note. Installation location of pulse generator for crankshaft is underneath starter motor.

Detach plug (1) from crankshaft pulse generator (2).

Release screw.

Installation

Replace aluminum screws.

Tightening torque 13 62 2AZ .

Withdraw pulse generator (2) from crankcase.

Scheme 127

Scheme 127

Installation

Replace sealing ring.

Note. Check stored fault messages. Now clear the fault memory.

12 14 524 Replacing pulse generator on exhaust camshaft (N52K)

IMPORTANTRead and comply with notes on PROTECTION AGAINST ELECTROSTATIC DAMAGE (ESD PROTECTION) .

Necessary preliminary tasks

  1. Read out fault memory of DME control unit
  2. Switch off ignition

Unlock plug (1) and remove.

Release screw.

Installation

Replace screw.

Tightening torque 13 62 1AZ .

Remove pulse generator (2).

Scheme 128

Scheme 128

Note. Check stored fault messages. Now clear the fault memory.

12 14 523 Replacing pulse generator on inlet camshaft (N52K)

IMPORTANTRead and comply with notes on PROTECTION AGAINST ELECTROSTATIC DAMAGE (ESD PROTECTION) .

Necessary preliminary tasks

  1. Read out fault memory of DME control unit
  2. Switch off ignition

Unlock plug (1) and remove.

Release screw.

Installation

Replace screw.

Tightening torque 13 62 1AZ .

Remove pulse generator (2).

Scheme 129

Scheme 129

Note. Check stored fault messages. Now clear the fault memory.

12 31 020 Removing and installing or replacing alternator (N52K)

IMPORTANTAluminium-magnesium materials.

No steel screws/bolts may be used due to the threat of electrochemical corrosion.

A magnesium crankcase requires aluminum screws/bolts exclusively.

Aluminum screws/bolts must be replaced each time they are released.

Aluminum screws/bolts are permitted with and without color coding (blue).

For reliable identification

Aluminum screws/bolts are not magnetic.

Jointing torque and angle of rotation must be observed without fail (risk of damage).

Necessary preliminary tasks

  1. Turn off ignition
  2. Disconnect «BATTERY NEGATIVE LEAD»(/bmw/z4/e89-2009-2013/remont/horns/#general-electrical-system-repair__61-20-900-disconnecting-and-connecting)
  3. Remove «INTAKE FILTER HOUSING»(/bmw/z4/e89-2009-2013/remont/fuel-system/#fuel-system-repair-n52__13-71-000-removing-and-installingreplacing)
  4. Remove «ALTERNATOR DRIVE BELT»(/bmw/z4/e89-2009-2013/remont/mechanical/#engine-repair-n52__11-28-010-replacing-alternator-drive)

Unlock plug (1) and remove.

Slacken nut (2).

Installation

Tightening torque 12 31 1AZ .

Disconnect battery positive lead from alternator.

Release screws (3) and remove alternator.

Installation

Replace aluminum screws.

Tightening torque 12 31 2AZ .

Scheme 130

Scheme 130

Assemble engine.

12 31... Replacing alternator belt pulley

Remove and install alternator drive belt.

Depending on alternator type, grip shaft with

  1. hexagon socket
  2. multi-tooth socket or
  3. Torx socket wrench

Release nut with special tool 12 7 110 .

Installation

Scheme 131

Scheme 131

12 31... Replacing alternator belt pulley (with overrunning clutch)

Special tools required

Remove and install alternator drive belt.

Grip alternator shaft with

  1. internal serration

Release nut with special tools 12 7 120.

Installation

Tightening torque 12 31 3AZ

Scheme 132

Scheme 132

12 32 501 Replacing voltage regulator

Necessary preliminary tasks

  1. Switch off ignition
  2. Disconnect battery negative lead
  3. Remove alternator

Bosch

Release protective caps (1).

Scheme 133

Scheme 133

Bosch

Release screw (1) and nuts (2), remove cover.

Scheme 134

Scheme 134

Bosch

Release screws and remove regulator switch (1) in direction of arrow.

Scheme 135

Scheme 135

Bosch

Installation

Clean contact surfaces and check pretension of contact spring, replace regulator switch if necessary.

Measurement A = min. 5 mm.

Check collector ring for wear and recondition if necessary.

Scheme 136

Scheme 136

Valeo

Slacken nut (1).

Slacken nut (2).

Release screws (3).

Release cover (4).

Scheme 137

Scheme 137

Valeo

Release screws.

Remove regulator switch (1) towards top.

Scheme 138

Scheme 138

Valeo

Installation

Clean contact surfaces and check pretension of contact spring, replace regulator switch if necessary.

Measurement A = min. 5 mm.

Check collector ring for wear and recondition if necessary.

Scheme 139

Scheme 139

Installation

Fit new regulator (1) with attached mounting sleeve (2) or locked carbon brush.

Pull off mounting sleeve (2) and replace with cover (3).

Scheme 140

Scheme 140

12 41 020 Removing and installing/replacing starter (N52K)

IMPORTANTAluminium-magnesium materials.

No steel screws/bolts may be used due to the threat of electrochemical corrosion.

A magnesium crankcase requires aluminum screws/bolts exclusively.

Aluminum screws/bolts must be replaced each time they are released.

Aluminum screws/bolts are permitted with and without color coding (blue).

For reliable identification

Aluminum screws/bolts are not magnetic.

Jointing torque and angle of rotation must be observed without fail (risk of damage).

Necessary preliminary tasks

  1. Switch off ignition
  2. Clamp off «BATTERY NEGATIVE LEAD»(/bmw/z4/e89-2009-2013/remont/horns/#general-electrical-system-repair__61-20-900-disconnecting-and-connecting)
  3. Remove «INTAKE AIR MANIFOLD»(/bmw/z4/e89-2009-2013/remont/mechanical/#engine-repair-n52__11-61-050-removing-and-installing)

Unlock plug (1) and remove.

Unfasten nut.

Tightening torque 12 42 2AZ .

Remove battery positive lead (2).

Scheme 141

Scheme 141

Release screw (1).

Installation

Replace aluminum screws.

Tightening torque 12 41 1AZ .

Unfasten screws (2).

Installation

Replace aluminum screws.

Tightening torque 12 41 2AZ .

Remove starter motor (3).

Scheme 142

Scheme 142

Installation

Check starter pinion and ring gear for damage. Replace starter if necessary.

Assemble engine.

12 41 041 Replacing solenoid switch

Turn off ignition.

Remove starter motor.

Release nut (1).

Remove cable lug (2).

Scheme 143

Scheme 143: 12 41 041 Replacing solenoid switch
CAUTIONDo not turn cable lug (2) while tightening down - risk of short circuit to starter motor housing. Tightening torque, see 12 41 4AZ in 12 41 STARTER MOTOR WITH MOUNTING

Release screws (1).

Scheme 144

Scheme 144

Remove solenoid switch (1) and spring (2).

Unhook pin (3).

Installation

Check pin (3) for wear and apply grease.

Scheme 145

Scheme 145

12 42 500 Replacing battery positive lead between starter, alternator and battery positive terminal (N52K)

Necessary preliminary tasks

  1. Read out fault memory of DME control unit
  2. Switch off ignition
  3. Disconnect «BATTERY NEGATIVE LEAD»(/bmw/z4/e89-2009-2013/remont/horns/#general-electrical-system-repair__61-20-900-disconnecting-and-connecting)
  4. Remove «INTAKE AIR MANIFOLD»(/bmw/z4/e89-2009-2013/remont/mechanical/#engine-repair-n52__11-61-050-removing-and-installing)

Open cover.

Slacken nut (1).

Tightening torque 12 42 3AZ .

Remove battery positive lead (2) from battery positive terminal.

Scheme 146

Scheme 146

Release nut (1) on starter.

Tightening torque 12 42 2AZ .

Disconnect battery positive lead from starter.

Release nut (2) on alternator.

Tightening torque 12 42 1AZ .

Release battery positive lead from retainer (3), feed out and remove.

Scheme 147

Scheme 147

Note. Check stored fault messages. Now clear the fault memory.

12 42 540 Replacing safety battery terminal (SBK)

CAUTIONObserve safety regulations. Investigate cause of triggering of safety battery terminal. To do so, read out fault memory of airbag control unit. Note fault messages stored in memory. Rectify faults. Then clear fault memory.

Use of safety battery terminal

  1. From model year 1998 in Series E38, E39, E46
  2. From 4/99 in E36/Z3
  3. in each of following new Series

The different models have different installation locations

Battery in engine compartment

Safety battery terminal is replaced with cable up to battery positive support point.

Safety battery terminal is omitted as from 03/2002 from all E46 LHD models with 4-cylinder engines.

Battery in luggage compartment behind side trim panel

Remove side trim panel.

Follow instructions for disconnecting and connecting battery.

Disconnect and cover battery negative lead.

Scheme 148

Scheme 148

Release front side trim panel partly and fold forward.

Scheme 149

Scheme 149

Battery in luggage compartment under floor trim panel

Follow instructions for disconnecting and connecting battery.

Fold back floor trim panel (1).

Lift cover (2) on battery negative lead.

Disconnect and cover battery negative lead (3).

Release nuts (4).

Remove battery cover.

Scheme 150

Scheme 150

Battery in luggage compartment under spare wheel

Remove spare wheel.

Release screws.

CAUTIONDo not kink air pipes.

Set air supply system (1) to one side.

Follow instructions for disconnecting and connecting battery.

Disconnect battery negative lead.

Scheme 151

Scheme 151

Disconnect supply cable (1) for vehicle electrical system.

Installation

Remove faulty fuses and carry out troubleshooting.

Scheme 152

Scheme 152
CAUTIONPay attention to interface. The repair cable is always a standard length. The heavy-current connector of the repair cable has a larger diameter than the battery positive lead. In some Series (e.g. E46 touring), the heavy-current connector of the repair cable can lead to installation problems. This is the case when the interface is in the area of the close-fitting trim panels. Find matching interface (e.g. approx. 10 cm behind rear seat backrest in E46 touring).

Lay repair cable parallel to battery positive lead.

Mark interface of battery positive lead at end of repair cable.

Scheme 153

Scheme 153

Release cable ties (1).

Disconnect plug connection (2).

Scheme 154

Scheme 154
CAUTIONDo not use bolt cutters or similar tools to cut through the cable. A cable end that has been squashed flat will no longer fit into the clamping sleeve.

Saw through battery positive cable at marked point with an iron saw.

Scheme 155

Scheme 155

Strip insulation - length (A) - from cable end.

Distance (A) = 15 mm.

Scheme 156

Scheme 156

Push heavy-current connector (1) over stripped cable end and screw into position.

Scheme 157

Scheme 157

Push shrink-fit hose (3) over repair cable.

Screw threaded sleeve (1) of repair cable (2) to heavy-current connector.

Scheme 158

Scheme 158

Push shrink-fit hose (1) over connecting point and shrink on with a hot-air blower (2).

Scheme 159

Scheme 159

Note. Heat up shrink-fit hose until it has settled completely around the connection point.

Scheme 160

Scheme 160

When laying the repaired battery positive cable, observe the following

  1. The shrink-fit hose must not be scuffed during any movement.
  2. The repair cable must not cause any disturbing noises during driving operation.

Note. Offsetting cutting line by approx. 10 cm produces excess length of battery positive lead (1). Lay battery positive lead (1) without kinks or abrasions. (Shown on E46 touring.)

Scheme 161

Scheme 161

12 51 001 Replacing wiring harness section for engine (N52K)

IMPORTANTRead and comply with notes on PROTECTION AGAINST ELECTROSTATIC DISCHARGE (ESD PROTECTION) .

Necessary preliminary tasks

  1. Read out fault memory of DME control unit
  2. Turn off ignition
  3. Disconnect «BATTERY NEGATIVE LEAD»(/bmw/z4/e89-2009-2013/remont/horns/#general-electrical-system-repair__61-20-900-disconnecting-and-connecting)
  4. Remove front «UNDERBODY PROTECTION»(/bmw/z4/e89-2009-2013/remont/axle-shafts/#front-axle-repair__51-47-490-removing-and-installingreplacing)
  5. Remove rear «UNDERBODY PROTECTION»(/bmw/z4/e89-2009-2013/remont/axle-shafts/#rear-axle-repair__51-47-491-removing-and-installingreplacing)
  6. Partially remove «WIRING HARNESS»(/bmw/z4/e89-2009-2013/remont/gauges-instrument-panels/#engine-electrical-system-repair-n52__12-51-100-replacing-wiring-harness) for ignition coils
  7. Remove «INTAKE AIR MANIFOLD»(/bmw/z4/e89-2009-2013/remont/mechanical/#engine-repair-n52__11-61-050-removing-and-installing)

Release bolts along line (1).

Tightening torque 12 90 1AZ .

Remove electronics box cover.

Unlock battery positive lead (1), detach and lay to one side.

Release locks (2) in direction of arrows and pull control unit upwards slightly.

Pull control unit (1) upwards slightly until plug (2) can be released from control unit in direction of arrow.

Unlock plug (2) and detach from control unit (1).

Unlock and detach all plugs from engine wiring harness in electronics box (1).

Unclip rubber grommet hold-down devices (2) and (3) and release engine wiring harness from electronics box.

Installation

Make sure rubber grommets are correctly seated (watertightness).

Scheme 162

Scheme 162

Long plug

Press in retaining lugs and withdraw lock (1) in direction of arrow from plug housing.

Scheme 163

Scheme 163

Press locking tabs (1) in direction of arrow and pull contact carrier (2) out of housing.

Scheme 164

Scheme 164

Press locking tab (1) in direction of arrow and pull contact carrier (2) out of housing.

Scheme 165

Scheme 165

Unlock locking tabs (1) in direction of arrow and pull contact carrier (2) out of housing.

Scheme 166

Scheme 166

Short plug

Press in retaining lugs (1) and withdraw lock (2) in direction of arrow from plug housing.

Scheme 167

Scheme 167

Press locking tabs (1) in direction of arrow and pull contact carrier (2) out of housing.

Unlock locking tabs (1) in direction of arrow and pull contact carrier (2) out of housing.

Unclip cable duct upper section (1) and expose wiring harnesses.

Scheme 168

Scheme 168

Unclip cable duct (1) and remove from cylinder head cover.

Scheme 169

Scheme 169

Unclip plug connection (1) from holder (2) and disconnect.

Unclip wiring harness from holder (2).

Unclip holder (2) from fuel rail and remove.

Scheme 170

Scheme 170

Detach connector strip (2) in direction of arrow.

Do not remove fuel rail (3) and fuel line (1).

Scheme 171

Scheme 171
Work stepNote
Unlock plug connections on control sensors and disconnect
Unlock plug on alternator and disconnect
Unlock plug connection on knock sensors and disconnect
Unlock plug on crankshaft sensor and disconnect
Unlock plug on starter motor and disconnect
Unlock plug on throttle valve assembly and disconnect
Unlock plug connections on monitoring sensors and disconnect
Unlock plug on oil condition sensor and disconnect
Unlock plug on tank vent valve and remove
Unlock plug on transmission and disconnect
Unlock plug on air-mass meter and disconnect
Unlock plug on differential-pressure sensor and disconnect
Unlock plug on intake system servomotors and disconnect
Unlock plug on eccentric shaft sensor and disconnect
Unlock plug on solenoid valves and disconnect
Unlock plug on coolant temperature sensor and disconnect
Unlock plug on oil pressure sensor and disconnect
Disconnect connector strip on fuel injectors
Unlock plug on A/C compressor and disconnect
Unlock plug on coolant thermostat and disconnect
Unlock plug on hydraulic valve and disconnect
Unlock plug on coolant pump and disconnect
Release earth connection and remove Tightening torque 12 90 3AZ .

WIRING HARNESS REPLACEMENT PROCEDURE

Release wiring harness if necessary from clips and retainers

Feed out wiring harness and remove.

Installation

Check wiring harness routing.

Check plug connections for correct seating.

Note. Check stored fault messages. clear fault memory.

12 51 100 Replacing wiring harness section for ignition coils (N52K)

IMPORTANTAluminium-magnesium materials.

No steel screws/bolts may be used due to the threat of electrochemical corrosion.

A magnesium crankcase requires aluminum screws/bolts exclusively.

Aluminum screws/bolts must be replaced each time they are released.

Aluminum screws/bolts are permitted with and without color coding (blue).

For reliable identification

Aluminum screws/bolts are not magnetic.

Jointing torque and angle of rotation must be observed without fail (risk of damage).

IMPORTANTRead and comply with notes on PROTECTION AGAINST ELECTROSTATIC DISCHARGE (ESD PROTECTION) .

Necessary preliminary tasks

  1. Read out fault memory of DME control unit
  2. Turn off ignition
  3. Disconnect «BATTERY NEGATIVE LEAD»(/bmw/z4/e89-2009-2013/remont/horns/#general-electrical-system-repair__61-20-900-disconnecting-and-connecting)
  4. Remove «IGNITION COIL COVER»(/bmw/z4/e89-2009-2013/remont/oem-general-information/#maintenance-and-general-information-repair-n52__11-00-removing-and-installingreplacing-acoustic)

Release bolts along line (1).

Tightening torque 12 90 1AZ .

Remove electronics box cover.

Unlock battery positive lead (1), detach and lay to one side.

Release locks (2) in direction of arrows and pull control unit upwards slightly.

Pull control unit (1) upwards slightly until plug (2) can be released from control unit in direction of arrow.

Unlock plug (2) and detach from control unit (1).

Unlock and detach all plugs (1) from ignition coil wiring harness in electronics box.

Unclip rubber grommet hold-down device (2) and release ignition coil wiring harness from electronics box.

Installation

Make sure rubber grommets are correctly seated (watertightness).

Scheme 172

Scheme 172

Press in retaining lugs and withdraw lock (1) in direction of arrow from plug housing.

Press locking tabs (1) in direction of arrow and pull contact carrier (2) out of housing.

Press locking tab (1) in direction of arrow and pull contact carrier (2) out of housing.

Unclip cable duct upper section (1) and expose wiring harnesses.

Unlock and remove clip (1).

Unlock all plugs on ignition coils and disconnect.

Unlock plug (2) on Valvetronic servomotor and disconnect.

Release wiring harness from retainers and cable ties (3).

Replace defective cable ties.

Release nuts (4) and remove earth connections.

Tightening torque 12 90 2AZ .

Feed out ignition coil wiring harness and remove.

Scheme 173

Scheme 173

Check wiring harness routing.

Check plug connections for correct seating.

Check stored fault messages.

clear fault memory.

12 61 285 Removing and installing/renewing oil level sensor for engine oil (N52K)

IMPORTANTRead and comply with notes on PROTECTION AGAINST ELECTROSTATIC DISCHARGE (ESD PROTECTION) .

Necessary preliminary work

  1. Switch off ignition
  2. Remove front «UNDERBODY PROTECTION»(/bmw/z4/e89-2009-2013/remont/axle-shafts/#front-axle-repair__51-47-490-removing-and-installingreplacing)
  3. Drain off «ENGINE OIL»(/bmw/z4/e89-2009-2013/remont/mechanical/#engine-repair-n52__11-00-engine-oil-service-n52k)

Release connector (1) and remove.

Unscrew nuts (2).

Tightening torque 12 61 2AZ .

Remove oil level sensor.

Installation note

Clean sealing surface on oil sump.

Replace gasket on oil level sensor.

An excessively low torque value will result in oil leaks.

An excessively high torque value will result in damage to the oil level sensor.

Top up engine oil.

Reinstall holder for ground cable.

Scheme 174

Scheme 174

Note. Check stored fault message. Delete fault memory.

12 61 280 Removing and installing/replacing oil pressure sensor (N52K)

WARNINGScalding hazard! Only perform this task on an engine that has cooled down.

Necessary preliminary tasks

  1. Remove «ACOUSTIC COVER»(/bmw/z4/e89-2009-2013/remont/oem-general-information/#maintenance-and-general-information-repair-n52__11-00-removing-and-installingreplacing-acoustic)

Installation location

Oil filter housing, front left.

Engine oil may emerge when oil pressure sensor is replaced; have a cleaning cloth ready.

Unlock plug (1) and remove.

Release oil pressure sensor (2).

Tightening torque 12 61 1AZ .

Installation

Check engine oil level, top up engine oil if necessary.

Scheme 175

Scheme 175