Engine Electrical System - Repair (n54) BMW Z4 E89

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

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.

Scheme 8

Choose repair kit.

Example: Repair kit, circular plug system D 2.5.

Scheme 9

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 10

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).

Scheme 11

Scheme 12

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

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 )

Scheme 13

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

Scheme 14

Crimp unused wire end to butt connector.

Scheme 15

Pull shrink-on sleeve over butt connector.

Scheme 16

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 17

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

High tension! - High tension!

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
5. Additional fault notes for troubleshooting

Oscillograms

1. Normal oscillators
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

1. Green = MOST ( M edia O riented S ystems T ransport) optical fibre
2. Yellow = ISIS ( I ntelligent S afety I ntegration S ystem) optical fibre
3. Orange = repair optical fibre cables

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

The following applies in general

To avoid damage, observe the following instructions

1. Avoid compressive and tensile loads
2. To ensure professional repairs, perform repair work only with BMW-approved or recommended special tools and spare parts
3. Make sure cables are laid without kinks or abrasions
4. Ensure non-contacting routing at sharp-edged body parts; use edge protection if necessary
5. Secure additionally laid cables/leads with cable ties

The following additionally applies

Shielded lines (coaxial lines)

Fibre-optic cable

Note. Fibre-optic cables are colored differently as follows

1. Green = MOST ( M edia O riented S ystems T ransport) optical fibre
2. Yellow = ISIS ( I ntelligent S afety I ntegration S ystem) optical fibre
3. Orange=repair fibre-optic cables

FlexRay

It is possible to repair the FlexRay. In the event of damage, the cables can be joined with conventional BUTT CONNECTORS AND HEAT-SHRINK HOSES .

Note. FlexRay lines may only reveal one separation point (bride); renew complete line if necessary The cable is a twisted cable. If possible, maintain twisted cable after repair

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

When replacing the DME/DDE control unit, observe the following

1. 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.
2. 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.
3. 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.
4. 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.
5. 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.

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.

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)

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 18

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 Workshop mode A = 10 mm 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 19

When working with diagnosis tools

1. Observe instructions in diagnosis tool

12 12 011 Replacing all spark plugs (N54)

Necessary preliminary work

1. Switch off ignition.
2. Remove «IGNITION COILS»(/bmw/z4/e89-2009-2013/remont/gauges-instrument-panels/#engine-electrical-system-repair-n54__12-13-511-replacing-ignition-coils) .

Clean spark plug slot with compressed air.

Unscrew the spark plugs with special tool 12 1 220 and an extension with a minimum kink of 8°.

Scheme 20

Attach new spark plug (1) 12 1 230 to special tool.

Scheme 21

Screw the spark plug hand-tight with special tool 12 1 230 into the cylinder head plug thread to the limit position.

Scheme 22

Installation note

Tighten the spark plugs with a torque wrench, special tool 12 1 220 and an extension with a minimum kink of 8°.

Observe tightening torque.

Tightening torque 12 12 2AZ .

12 13 Carrying out engine cleaning (N54, N53, N43)

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

Oscillograms

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

Check

1. Secondary signal for stationary ignition distribution

12 13 511 Replacing ignition coils (N54)

Necessary preliminary tasks

1. Read out fault memory of DME control unit.
2. Switch off ignition.
3. Remove «ACOUSTIC COVER»(/bmw/z4/e89-2009-2013/remont/oem-general-information/#maintenance-and-general-information-repair-n54__11-removing-and-installingreplacing-acoustic-cover)
4. Remove right «TENSION STRUT»(ref-381258-S30910208292010122800000)

Unlock plug catch (1) of ignition coil (2) and disconnect plug.

Pull ignition coil (2) up and out.

This procedure is applicable to all ignition coils.

Scheme 23

Installation

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

Scheme 24

Installation

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

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

The plug catch must snap into place without great effort.

Scheme 25

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)

Refer to "Diagnosis and Coding" service information bulletins on subject of coding.

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)

Refer to "Diagnosis and Coding" service information bulletins on subject of programming.

12 14 600 Removing/replacing knock sensors (N54)

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-n54__11-61-050-removing-and-installing) .

Unlock plug (1) and remove.

Feed out plug (1) behind feed line, remove FEED LINE if necessary.

Scheme 26

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

Installation

1. Replace aluminum screws.
2. Tightening torque «13 62 5AZ»(/bmw/z4/e89-2009-2013/remont/fuel-system/#fuel-system-tightening-torques-n54) .

Scheme 27

Installation

Clean contact surface of knock sensors on engine block.

Scheme 28

Note. Add final details to vehicle.

Check stored fault message.

Now clear the fault memory.

12 14 550 Replacing control unit (DME) (N54)

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)

Replacement

1. Carry out programming/encoding
2. If no data can be read out from the previous control unit, carry out injection quantity adjustment (description at end of instruction).

Switch off ignition.

Release bolts along line (1).

Tightening torque 12 90 1AZ .

Remove electronics box cover.

Scheme 29

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 30

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 31

Lift out control unit (1).

Scheme 32

Injector adjustment

If the DME control unit has been replaced, it will also be necessary to carry out adjustment of the injectors!

Injector adjustment is carried out with the aid of so-called adjustment values.

The adjustment values are printed in two blocks of three digits on each injector.

The adjustment values must be stored in the new control unit!

Scheme 33

If injector adjustment is not carried out, the engine may run roughly or fail to start.

Read off the adjustment values and enter according to the installation location (cylinder) of the injectors

1. Connect DIS Tester
2. Identify car
3. Select "Function selection"
4. Select "Service functions"
5. Select "Engine electronics"
6. Select "Adjustment programs"
7. Select "Adjust injectors"
8. Select "Test schedule"
9. The adjustment value must be entered for each cylinder.

Scheme 34

Note. Check stored fault message. clear fault memory.

12 14 521 Replacing crankshaft pulse generator (N54)

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 4AZ .

Scheme 35

Withdraw pulse generator (2) from crankcase.

Installation

Replace sealing ring.

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

12 14 524 Replacing pulse generator on exhaust camshaft (N54)

Necessary preliminary tasks

1. Read out fault memory of DME control unit
2. Switch off ignition
3. Remove «FAN COWL»(/bmw/z4/e89-2009-2013/remont/cooling-system-mechanical/#cooling-system-repair-n54__17-11-035-removing-and-installingreplacing)

Unlock plug (1) and remove.

Release screw.

Tightening torque 13 62 3AZ .

Remove pulse generator (2).

Scheme 36

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

12 14 523 Replacing pulse generator on inlet camshaft (N54)

Necessary preliminary tasks

1. Read out fault memory of DME control unit
2. Switch off ignition
3. «REMOVE FAN COWL»(/bmw/z4/e89-2009-2013/remont/cooling-system-mechanical/#cooling-system-repair-n54__17-11-035-removing-and-installingreplacing)

Unlock plug (1) and remove.

Release screw.

Tightening torque 13 62 3AZ .

Remove pulse generator (2).

Scheme 37

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

12 14 651 Replacing suction pressure sensor on charge-air duct (N54)

Necessary preliminary tasks

1. Read out fault memory of DME control unit
2. Switch off ignition
3. Remove «INTAKE FILTER HOUSING»(/bmw/z4/e89-2009-2013/remont/fuel-system/#fuel-system-repair-n54__13-71-000-removing-and-installingreplacing)

Note. The installation location of the suction pressure sensor is at the rear end of the charge-air duct.

Unlock plug (1) and remove.

Release screws and pull suction pressure sensor (2) out of charge-air duct.

Tightening torque 13 62 2AZ .

Scheme 38

Installation

Check sealing ring for damage. Replace sealing ring if damaged.

When installing, coat sealing ring with suitable antiseize agent.

Scheme 39

Note. Add final details to vehicle. Check stored fault messages. Now clear the fault memory.

12 14 650 Replacing suction pressure sensor on intake air manifold (N54)

Necessary preliminary tasks

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

Note. The installation location of the suction pressure sensor is at the rear end of the intake air manifold.

Unlock plug (1) and remove.

Release screws and pull suction pressure sensor (2) out of intake air housing.

Tightening torque 13 62 2AZ .

Scheme 40

Installation

Check sealing ring for damage. Replace sealing ring if damaged.

When installing, coat sealing ring with suitable antiseize agent.

Scheme 41

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

12 31 020 Removing and installing or replacing alternator (N54)

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) and cover
3. Remove «INTAKE FILTER HOUSING»(/bmw/z4/e89-2009-2013/remont/fuel-system/#fuel-system-repair-n54__13-71-000-removing-and-installingreplacing)
4. Release «CHARGE-AIR DUCT»(/bmw/z4/e89-2009-2013/remont/fuel-system/#fuel-system-repair-n54__13-71-160-removing-and-installingreplacing) at front, do not remove
5. Remove alternator «DRIVE BELT»(/bmw/z4/e89-2009-2013/remont/mechanical/#engine-repair-n54__11-28-010-replacing-drive-belt)

Note. In order to remove the alternator, it is necessary to remove the air-conditioning compressor for the air conditioning system. In so doing: Do not draw off A/C system refrigerant. Do not detach refrigerant lines from A/C compressor. Do not remove A/C compressor; instead, remove from bracket only and place to one side. See 64 52 521 REPLACING AIR CONDITIONING COMPRESSOR (N54) .

Note. For purposes of improved clarity, illustrations and description show A/C compressor removed.

Release bolts a few turns until bracket (1) is loose. Do not remove bracket (1).

Tightening torque, see 64 52 A/C COMPRESSOR .

Scheme 42

Unlock plug (1) and remove.

Remove protective cap (2) and release nut underneath.

Tightening torque 12 42 1AZ .

Remove battery positive lead.

Release screws (3).

Tightening torque 12 31 1AZ .

Tightening torque 12 31 2AZ .

Remove alternator.

Scheme 43

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

TIGHTENING TORQUE, 12 31 2AZ/12 31 3AZ .

Scheme 44

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

Remove and install alternator drive belt.

Grip alternator shaft with

1. internal serration

Release nut with special tools 12 7 120.

Installation

Tightening torque, see 12 31 3AZ in 12 31 ALTERNATOR WITH DRIVE AND MOUNTING PARTS .

Scheme 45

12 32 501 Replacing voltage regulator

Necessary preliminary tasks

1. Switch 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 alternator

Bosch

Release protective caps (1).

Scheme 46

Bosch

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

Scheme 47

Bosch

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

Scheme 48

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 49

Valeo

Slacken nut (1).

Slacken nut (2).

Release screws (3).

Release cover (4).

Scheme 50

Valeo

Release screws.

Remove regulator switch (1) towards top.

Scheme 51

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 52

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 53

12 41 020 Removing and installing/replacing starter motor (N54)

Necessary preliminary tasks

1. Switch 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 AIR MANIFOLD»(/bmw/z4/e89-2009-2013/remont/mechanical/#engine-repair-n54__11-61-050-removing-and-installing)

Unlock plug (1) and remove.

Release nuts (2) and disconnect battery positive leads.

Tightening torque 12 42 2AZ .

Release screws (3).

Installation

Replace aluminum screws.

Tightening torque 12 41 1AZ .

Remove starter motor (4).

Scheme 54

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 55

Release screws (1).

Scheme 56

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

Unhook pin (3).

Installation

Check pin (3) for wear and apply grease.

Scheme 57

12 42 500 Replacing battery positive lead between starter, alternator and battery positive terminal (N54)

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-n54__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 58

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 59

Note. Add final details to vehicle. Check stored fault messages. Now clear the fault memory.

12 42 540 Replacing safety battery terminal (SBK)

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 60

Release front side trim panel partly and fold forward.

Scheme 61

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 62

Battery in luggage compartment under spare wheel

Remove spare wheel.

Release screws.

Set air supply system (1) to one side.

Follow instructions for disconnecting and connecting battery.

Disconnect BATTERY NEGATIVE LEAD .

Scheme 63

Disconnect supply cable (1) for vehicle electrical system.

Installation

Remove faulty fuses and carry out troubleshooting.

Scheme 64

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 65

Release cable ties (1).

Disconnect plug connection (2).

Scheme 66

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

Scheme 67

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

Distance (A) = 15 mm.

Scheme 68

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

Scheme 69

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

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

Scheme 70

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

Scheme 71

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

Scheme 72

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 73

12 51 001 Replacing wiring harness section for engine (N54)

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. Partially remove «WIRING HARNESS»(/bmw/z4/e89-2009-2013/remont/gauges-instrument-panels/#engine-electrical-system-repair-n54__12-51-100-replacing-wiring-harness) for ignition coils and injectors
5. Remove «INTAKE AIR MANIFOLD»(/bmw/z4/e89-2009-2013/remont/mechanical/#engine-repair-n54__11-61-050-removing-and-installing)
6. Remove front «UNDERBODY PROTECTION»(ref-381258-S36346312162010122800000)
7. Remove rear «UNDERBODY PROTECTION»(ref-381258-S25614082772010122800000)

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 74

Long plug

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

Scheme 75

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

Scheme 76

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

Scheme 77

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

Scheme 78

Short plug

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

Scheme 79

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.

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

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

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 80

Unscrew screws (1).

Tightening torque 12 90 4AZ .

Remove cable duct (2).

Scheme 81

ENGINE WIRING HARNESS REPLACEMENT PROCEDURE

Release wiring harness 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 and injectors (N54)

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 «ACOUSTIC COVER»(/bmw/z4/e89-2009-2013/remont/oem-general-information/#maintenance-and-general-information-repair-n54__11-removing-and-installingreplacing-acoustic-cover)

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).

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).

Release nuts (2) and remove earth connections.

Tightening torque 12 90 2AZ .

Unlock all plugs on ignition coils and injectors and detach.

Release wiring harness (3) from retainers and cable ties, feed out and remove.

Replace defective cable ties.

Scheme 82

Note. Check wiring harness routing. Check plug connections for correct seating. Check stored fault messages. clear fault memory.

12 61 285 Removing and installing/replacing oil level sensor for engine oil (N54)

Necessary preliminary work

1. Switch off ignition
2. Remove front «UNDERBODY PROTECTION»(ref-381258-S36346312162010122800000)
3. Drain off «ENGINE OIL»(/bmw/z4/e89-2009-2013/remont/mechanical/#engine-repair-n54__11-00-engine-oil-service-n54)

Release connector (1) and remove.

Unscrew nuts.

Tightening torque 12 61 2AZ .

Remove oil level sensor (2).

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.

Scheme 83

Note. Check stored fault message. Delete fault memory.

12 61 280 Removing and installing/replacing oil pressure sensor (N54)

Necessary preliminary tasks

1. Switch off ignition
2. Remove «ACOUSTIC COVER»(/bmw/z4/e89-2009-2013/remont/oem-general-information/#maintenance-and-general-information-repair-n54__11-removing-and-installingreplacing-acoustic-cover)

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 84

See also:
• 12 1 220
• 12 12 2AZ
• ACOUSTIC COVER
• INTAKE AIR MANIFOLD
• FEED LINE
• 13 62 5AZ
• ESD PROTECTION (ELECTRO STATIC DISCHARGE)
• BATTERY NEGATIVE LEAD
• FAN COWL
• INTAKE FILTER HOUSING
• CHARGE-AIR DUCT
• DRIVE BELT
• 64 52 521 REPLACING AIR CONDITIONING COMPRESSOR (N54)
• 64 52 A/C COMPRESSOR
• 12 41 4AZ
• ENGINE OIL
• BUTT CONNECTORS AND HEAT-SHRINK HOSES
• IGNITION COILS
• INSTRUCTIONS
• WIRING HARNESS