electronic BMW 525i 2001 E39 Workshop Manual
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Technical contact inlormation I
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Errata information
We will evaluate submissions and post appropriate editorial
changes online as text errata or tech discussion. Appropriate
errata will be incorporated with the
boolc text in future printings.
Read errata information for this book before beginning work on
your vehicle. See the following web address tor additional
information:
http://unw.BentleyPublishers.com/errata/
WARNING-important safety notice
Do not use this manual unless vou are familiar with basic automotive reoair orocedures and safe
workshoo oracfices. This manual illustrates
the workshop procedures requked formoslservice work. It is not a subsiituti for full and up-to-date information from thevehiclemanufaciurer
or for proper training as an automotive technician. Note that it is not possible for us to anticipate all of the ways or conditions under which
vehicles may be serviced or to provide cautions as to all of the possible hazards that may result.
The vehicle manufacturer will continue to issue service information updates and parls retrofits
after the editorial closing of this manual. Some
of lhese updates and retrofits will apply lo procedures and specifications in this manual. We regret that we cannot supply updates to
purchasers of this manual.
We have endeavored to ensure the accuracy
of the information in this manual. Please note, however, that considering the vast quantity and
the complexity of the service information involved, we cannot warrant the accuracy or completeness of the information contained in this
manual.
FOR
THESE REASONS, NEITHER THE PUBLISHER NOR THE AUTHOR MAICES ANY WARRANTIES, EXPRESS OR IMPLIED, THATTHE INFORMATION IN THIS BOOK IS FREE OF ERRORS OR OMISSIONS. AND WE EXPRESSLY DISCLAIM THE IMPLIED WARRANTIES OF MERCHANTABILTTY AN0 OF FITNESS FOR A PARTICULAR PURPOSE, EVEN IFTHE PUBLISHER OR AUTHOR HAVE BEEN ADVISED OFA PARTICULAR PURPOSE, AND EVEN IF A PARTICULAR
1 PURPOSE IS INDICATED IN THE MANUAL. THE PUBLISHER AND AUTHOR ALSO DISCLAIM ALL LlABlLrrY FOR DIRECT. INDIRECT. INCIDENTAL OR 1 I CONSEQUENTIAL DAMAGES THAT RESULT FROM ANY USE OFTHE EXAMPLES, INSTRUCTIONS OR OTHER INFORMATION INTHIS BOOK. IN NO EVENT 1
I Your common sense and oood iudoment are crucial to safe and successful service work. Read orocedures throuoh before startino them. I . -- - -~ ~ ---~. - ~ ~~ Think about whether the condition of your car, &r level of mechanical skill, or your level of reading compreh&sion might resill in or
contribute in some way to an occurrence which might cause you injuly, damage your car, or result in an unsafe repair. If you have doubts
for these or other reasons about your ability to pelform safe repair work on your car, have the work done at an authorized BMW dealer or
other qualified shop.
Part numbers listed in this manual are for identification purposes only, not for ordering. Always check wilh your authorized BMW dealer to
verify part numbers and availability before beginning service work lhat may require new
park.
Before anempting any work on your BMW, read the 001 General Warnings and Cautions, and any WARNING or CAUTION that
accompanies a procedure in the service manual. Review the WARNINGS and CAUTIONS each time you prepare to work on your BMW.
I Spec a too s req.1 red to perlorm cena n service operations arc oenl fed n the manLa an0 arc recomrnenoeo lor JSC Jse ol loo s olner than those recommended In lh s serv ce manual may be oelnmcnlal lo lrlc car's sale open1 on as rvec as lne salely 01 lne person servcng I the car. I
Copies of this manual may be purchased from most automotive accessories and parts dealers specializing in BMW automobiles, from
selected booksellers, or directly from the publisher.
This manual was published by Robert Bentley,
Inc., Publishers. BMW has not reviewed and does not vouch for the accuracy of the
technical specifications and procedures described in this manuai.
Libratv of Conaress Cataloaino-in-Publication Data " " -
BMW 5 Series (E39) : service manual : 523. 528i, 530i. 540i, sedan, sport wagon, 1997,
1998, 1999,2000,2001,2002
~Acludes index.
ISBN 0-8376-0317-X (obi<) ,, , 1. BMW 5 series automobiles--Maintenance and repair--Handbooks manuals, etc. 1.
Robert Bentley, Inc.
TL215.8258623 2003 629.28'722--dc23 2003052231
Bentley Stock No. 8502
Editorial closing 08/03
090807 10987654
The paper used in this publication is acid
free and meets the requirements of the National Standard for Information Sciences-
Permanence of Paper for Printed Library Materials. @
OCopyright 2007 Robert Bentley. Inc. Bentiey Publishers is a trademark of Robert Bentley, Inc.
All rights reserved. All information contained in this manual is based on the information available to the publisher at the time of editorial
closing. The right is reserved to make changes at any time without notice. No part of this publication may be reproduced, stored in a
retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or
ofhenvise, without the
prior written consent of the publisher. This includes text, figures, and tables. All rights reserved under Berne and Pan-American Copyright
conventions.
Cover photos of car exteriors by Jonathan Richard for
Bentley Publishers @ Robert Bentley, Inc. Cover design and use of blue band on
spine and back cover are trademarks
of Bentley Publishers. All rights reserved.
Manufactured in the United States of America
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Selected Boolcs and Repair Information from Bentley Publishers
MINI Cooper
MINI Cooper Service Manual: 2002-2004 Bc,illc!! Pirl~lisl!~~ ISBN 0-8376-1068-0 AlexZanardi - My Swectest Victory rllex Zmmrdi itjill! Ginrz11,cn Gns~x~ri,,i ISBN (1-8376-1249-7
BMW 3 Series IE36) Scrvire Manual: 1992-1998,318ilisliC. 323is/iC, 3?5i/is/iC, 328ilisliC, M3 Be~iili.!~ Pirl?lisliers ISBN 0-8376-0326-9
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5 Series Scrvicc Manual: 1997-2002 525i, 528i. 530i. 540i, Sedan, Sport Wagon Bcrrlluy P~rlilishens ISBN 0-8376-0317-X
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Bosch Handbook for Diesel-Engine Managcmcnt Ril1iei.t Bosdl, ClrrbH ISBN 0-8376-1051-6
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Page 20 of 1002
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01 0-1 0
General
Electrical testing
Many electrical problems can be understood and solved with
only a little fundamental knowledge of how electrical circuits
function.
Electrical current
only flows in a complete circuit. To operate.
every electrical device in the car requires a complete circuit
including a voltage source and a path to ground. The positive
(+) side of the battery is the original voltage source, and
ground is any return path to the negative
(-) side of the bat-
tery, whether through the wiring harness or the car body. Ex-
cept for portions of the charging system, all electrical current
in the car is direct current (DC) and flows from positive
(+) to
negative
(-).
4 Switches are used to turn components on or off by complet-
ing or interrupting the circuit.
A switch is "open" when the cir-
cuit is interrupted, and "closed" when the circuit is completed.
See
600 Electrical System-General for electrical trouble-
(LW, 1 shooting
Wire repairs
Light bulb
(consumer) ' - Repairs to a wiring harness require special care to make the
repair permanent. The wire ends must be clean.
if frayed or
Car body otherwise damaged, cut off the end and remove enough insu- (ground) i Battery lation to complete the repair. if the wire is too short, splice in a BOZLiEL new piece of wire of the same size and make two connec-
tions.
Use connectors that are designed for the purpose. Crimped
on orsoldered-on connectors are best. Crimp connectors and
special crimping pliers are widely available. If soldering, use
needle nose pliers to hold the wire near the solder joint and
create a "heat dam". This keeps the heat and the solder from
traveling up the wire. Always use a solder made specifically
for electrical
work (rosin core).
NOJE-
Twisting wires together to make a repair is not recommend-
ed. Corrosion and vibration will eventually spoil the connec-
tion and may lead to irreparable damage to sensitive
electronic components.
Insulate the finished connection. Electronics stores can sup-
ply heat-shrinkable insulating tubing that can be placed on to
the wire before connecting, slid over the finished joint, and
shrunic to a tight fit with a heat gun or hair dryer. The next best
alternative is electrical tape. Make sure the wire is clean and
free of
solder flux or other contamination. Wrap the joint tight-
ly to seal out moisture. See
600 Electrical System-General
for more information.
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- - ..
General
Many of the maintenance and repair tasks in this manual call
forthe installation of new parts, orthe use of new gaskets and
other materials when reinstalling parts. Most often, the parts
that will be needed should be on hand before beginning the
job. Read the introductorytext and the complete procedure
to
determine which parts will be needed.
NOTE-
For some biggerjobs, partial disassembly and inspection is
required to determine a complete parts list. Read the proce-
dure carefully and, if necessary, male other arrangements to
get the necessary parts while your car is disassembled.
Genuine BMW parts
Genuine BMW replacement parts from an authorized BMW
dealer are designed and manufactured to the same high stan-
dards as the original parts. They will be the correct material.
manufactured to same specifications, and guaranteed to fit
and work as intended. Most genuine BMW parts carry a limit-
ed warranty.
Many independent repair shops make a point of using genu-
ine
BMW parts, even though they may at times be more ex-
pensive than parts from other sources. They know the value
of doing the job right with ihe right parts. Parts from other
sources can be as good as BMW parts, particularly if manu-
factured by one of
BMW's or~ginal equipment suppliers, but it
is often difficult to know.
BMW is constantly updating and improving their cars, often
malting improvements during a given model year. BMW may
recommend a newer, improved part as a replacement, and
your authorized dealer's parts department will know about it
and provide it. The BMW parts organization is best equipped
to deal with your BMW parts needs.
Non returnable parts
Some parts cannot be returned, even for credit. The best ex-
ample is electrical parts, which are almost universally consid-
ered non returnable. Buy electrical parts carefully, and be as
sure as possible that a replacement is needed, especially for
expensive parts such as electronic control units. It may be
wise to let an authorized BMW dealer or other qualified shop
confirm your diagnosis before replacing an expensive non re-
turnable
Dart.
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.
General
Torque wrench
A torque wrench is used to precisely tighten threaded fasten-
ers to a predetermined value. Many of the repair procedures
in this manual include BMW-specified torque values
in New-
ton-meters (Nm) and the equivalent values in foot-pounds
(ft-
Ib).
4 Several types of torque wrenches are available. An inexpen-
sive beam-type (top) is adequate but must be read visually. A
ratchet-type (bottom) can be preset to indicate (click) when
the torque value has been reached. They all do the same job,
but offer different convenience features at different prices.
The most convenient ones have a built-in ratchet, and can be
preset to indicate when a specific torque value has been
reached. Follow the wrench manufacturer's directions
for use
to achieve the greatest accuracy.
A torque wrench with a range up to about 150 Nm (1 10 ft-lb) BOIBFNG has adequate capacity for most of the repairs covered in this
manual. For recommended torque values of
10 Nm orbelow,
the English system equivalent is given in inch-pounds (in-lb).
These small values may be most easily reached using a
torque wrench calibrated in inch-pounds. To convert
inch-
pounds to foot-pounds, divide by 12.
Digital multimeter
4 Many of the electrical tests in this manual call for the mea-
surement of resistance (ohms) or voltage values. For safe
and accurate tests of sensitive electronic component and
systems, a multimeter or digital
volt/ohm meter (DVOM) with
high input impedance (at least
10,000Sr) should be used.
Some meters have automotive functions such as dwell and
pulse width that are useful for troubleshooting ignition and
fuel injection problems.
CAUTIOI\C
Vehicle electronic systems may be damaged by the high cur-
rent draw of a test light with a normal incandescent bulb. As
a general rule, use a high impedance digital multimeter or an
LED test light for all electrical testing.
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Maintenance
Service Interval lndicator (Sll)
The BMW Service Interval lndicator (SII) notifies the driver
when oil change and other service is required. The
Sll dis-
plays the phrase "OIL SERVICE"
or"INSPECTI0N" and 7
light emitting diodes (LEDs) in the Instrumentcluster: 5green,
one yellow and one red.
For the
1997 and later 5 Series, BMW introduced an oil
change interval based on fuel consumption. The advantages
of this system are:
Fuel consumption is an accurate method of determining
engine load and the need for service.
The processing electronics are simple.
Resetting of indicator before the scheduled time will not
affect the time to the next service.
4 The Sll is programmed to measure a set volume of con-
sumed fuel. This volume varies between models, dependent
on vehicle and engine size. The
Sil control unit receives a
signal from the engine control module (ECM) when the vehi-
cle is in use. As
20% of the programmed fuel volume is con-
sumed, one of the green LEDs will go out. Each successive
20% of fuel consumption will cause the next LED to go out
until
100% of the measured volume has been consumed. At
this point the yellow LED will come on, indicating that service
is due. When
108% of the measured volume has been con-
sumed, the red LED will illuminate, indicating that service is
overdue.
Service Interval Indicator (SII), resetting
After the specified maintenance has been carried out, the Sll
memory should be reset.
NOTE-
For reference, the BMW oil service requirements are approx-
imately equivalent to the maintenance tliat other European
manufacturers specify at intervals with a maximum of every
15.000 miles or I2 months.
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Maintenance
< Remove NC compressor belt:
Loosen tensioner mounting fasteners (arrows)
Swing tensioner down to remove belt.
4 To reinstall compressor belt:
Route belt over pulleys.
* Pretension belt by turning adjuster clockwise (arrow) to
stop.
- Tighten tensioner mounting bolts (A).
Tightening torques
Fan clutch to coolant pump (left- hand thread)
with BMW tool
11 5 040
30 Nm (22 ft-lb)
without BMW tool 11 5 040
40 Nm (29 ft-lb)
Tensioner to engine block
8.8 grade
22 Nm (16 ft-lb)
10.9 grade (Ilquid-cooled alternator) 30 Nm (22 ft-lb)
Idle speed
Engine idle speed can change due to a number of factors, in-
cluding normal wear. The idle speed is electronically adaptive
and not adjustable. See
130 Fuel Injection for more informa-
tion.
Catalytic converter and oxygen sensors
OBD II enhanced emission standards require the engine
control module (ECM) to monitor the oxygen content in the
exhaust with oxygen sensors placed before and after the cat-
alytic converter. This allows for tighter control of tail pipe
emissions and also allows the ECM to diagnose converter
problems. If the ECM detects that catalytic converter or oxy-
gen sensor efficiency has degraded past a certain
prepro-
grammed limit, it will turn on the malfunction indicator light
(MIL), and store a diagnostic trouble code (DTC) in the ECM.
See OBD On-Board Diagnostics for more information on
OBD
ll systems.
Replacement of oxygen sensors at the specified intervals
he engine and emission control system will
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Engine identifying features
4 The M52 engine (MY97-98 528i) used a single on-off vari-
able intake valve timing system (called VANOS). The cylinder
block is cast iron and the cylinder head is aluminum. The en-
gine management system is Siemens MS 41
.I and features
NGK-type (0-5 volt) oxygen sensors.
NOTE-
VANOS is an acronym based on the German words Variable
Nocltenwellen Steuerung (variable camshaft timing).
4 The M52 TU engine (MY99-00 5281) and the M54 engines
(MY01-02 525il530i) are fitted with double VANOS. The en-
gine
blocits are constructed of aluminum alloy with cast iron
cylinder sleeves.
4 The double VANOS (variable camshaft control) system incor-
porates true variable control of both the
intake and exhaust
camshafts, as compared to the single VANOS system on the
M52 engine
(onloff control of the intaite camshaft only).
The M54 engines use a fully electronic throttle control (drive
by wire). There is no accelerator cable connecting the throttle
pedal to the throttle housing in these cars.
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100-4
I Engine-General
The M62 90" V8 engine uses four valves per cylinder, double
overhead camshafts and light alloy cylinder head and cylin-
der
bloclc engine construction.
On 1997 and 1998 540i models, Bosch engine management
systems are utilized. Table a lists engine management sys-
tem applications.
4 For the 1999 model year, the M62 TU VANOS engine was in-
troduced to the 540i models. This engine is primarily a carry-
over from the earlier M62 engine, but contains many unique
identifying components and technology:
Variable camshaft timing (VANOS) for the intake valves.
Bosch ME 7.2 engine management system with electronic
throttle control. There is no accelerator cable connecting
the throttle pedal to the throttle housing in these cars.
Compact water-cooled generator (alternator).
E39 vehicles are equipped with sophisticated self-diagnostic
engine management systems. These systems monitor and
store diagnostic fault information. If the malfunction indicator
lamp (MIL) illuminates, the first diagnostic test should be to
connect a dedicated scan tool for BMW automobiles and in-
terrogate the fault memory.
If the malfunction indicator light (MIL) comes on orflashes, it
indicates that an emissions-related fault has occurred and
that fault information is stored in memory within the ECM.
4 The MIL in E39 cars displays one of these warning graphics
in the instrument cluster.
The diagnostic capabilities of these systems have the poten-
tial to save hours of diagnostic time and prevent incorrect
5 placement. See OBD On-Board Diagnostics.
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Two common causes of driveability problems are incorrect
system voltage and bad grounds.
System voltage
Digital motor electronics (DME) requires that the system (bat-
tery) voltage be maintained within a narrow range of DC volt-
age.
DC voltage levels beyond or below the operating range,
or any
AIC voltage in the electrical system can cause havoc.
When troubleshooting an illuminated MIL, make sure the bat-
tery is fully charged and capable of delivering all its power to
the electrical system. An undercharged battery can amplify
AIC alternator output ripple.
To
make a quick check of the battery charge, measure the
voltage across the battery terminals with all cables attached
and the ignition off.
Afully charged battery will measure 12.6
volts or slightly more, compared to 12.1 5 volts for a battery
with a 25% charge.
The DME system operates at low voltage and current levels,
making it sensitive to small increases in resistance. The elec-
trical system is routinely subjected to corrosion, vibration and
wear, so faults or corrosion in the wiring harness and connec-
tors are not uncommon. Check the battery terminals
forcorro-
sion or loose cable connections. See 121 Battery, Starter,
Alternator for additional information.
If a battery cable connection has no
v~sible faults but is still
suspect, measure the voltage drop across the connection. A
large drop indicates excessive resistance, meaning that the
connection is corroded, dirty, or damaged. Clean or repairthe
connection and retest.
NOTE-
For instructions on conducting a voltage drop test and other
general electrical troubleshooting information, see
600 Elec-
trical System-General.
Visually inspect all wiring, connectors, switches and fuses in
the system. Loose or damaged connectors can cause inter-
mittent problems, especially the small terminals in the ECM
connectors. Disconnect the wiring harness connectors to
check for corrosion, and use electrical cleaning spray to re-
move contaminants.
Main grounds
Good grounds are critical to proper DME operation. If a
ground connection has no visible faults but is still suspect.
measure the voltage drop across the connection. A large volt-
age drop means high resistance. Clean or repair the connec-
tion and retest.
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