1999 BMW 535i M62TU Engine Workshop Manual

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M62 TU VANOS CONTROL
As the engine camshafts are rotated by the primary and secondary timing chains, the
ME7.2 control module activates the VANOS solenoids via a PWM (pulse width modulated)
ground signal based on a program map. The program is influenced by engine speed, load,
and engine temperature.
•Shown below: In its inactive or default position, the valves direct 100% engine oil pres-
sure flow to achieve max “retard” VANOS positioning
•Top of next page: As the Pulse Width Modulation (PWM) increases on the control sig-
nal, the valve progressively opens the advance oil port and proportionately closes the
retarded oil port.
Oil pressure pushes the piston toward the advance position. Simultaneously the oil
pressure on the retarded side (rear) of the piston is decreased and directed to the vent
port in the solenoid valve and drains into the cylinder head.
•Bottom of next page: At maximum PWM control, 100% oil flow is directed to the front
surface of the piston pushing it rearward to maximum advance.
Varying the pulse width (on time) of the solenoids control signals proportionately regulates
the oil pressures on each side of the pistons to achieve the desired VANOS advance angle.

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VANOS SERVICE NOTES
VALVE TIMING PROCEDURES
Refer to TIS for complete Valve Timing Procedures.M62 TU valve timing adjustment is sim-
ilar to the previous non VANOS M62 engine with the exceptionof setting the VANOS
transmissions to their max retard positions with an ohmmeter and attaching the camshaft
gears to each camshaft with single reverse threaded bolts.
• After locking the crankshaft at TDC, the camshaft alignment tools (P/N 90 88 6 112 440)
are placed on the square blocks on the rear of the camshafts locking them in place.
• The exhaust camshaft sprockets and VANOS transmission units with timing chains are
placed onto their respective camshafts.
• The exhaust camshaft sprockets and VANOS transmissions are secured to the
camshafts with their respective single, reverse threaded bolt. Finger tighten only at this
point. Install the chain tensioner into the timing chain case and tension the chain.
• Connect an ohmmeter across two of the three pin contacts on the front edge of one of
the VANOS transmissions. Twist the inner hub of transmission to the left (counter clock-
wise). Make sure the ohmmeter indicates closed circuit. This verifies that the trans-
mission in the default max retard position.
• Using an open end wrench on the camshaft to hold it in place, torque the VANOS trans-
mission center bolt to specification.
CAMSHAFT IMPULSE WHEEL POSITION TOOLS
The camshaft impulse wheels require a special tool set
to position them correctly prior to torquing the retaining
nuts.
The impulse wheels are identical for each cylinder
bank. The alignment hole in each wheel must align
with the tool’s alignment pin. Therefore the tools are
different and must be used specifically for their bank.
The tool rests on the upper edge of the cylinder head
and is held in place by the timing case bolts.
Refer to the TIS repair manual section for complete
information.
BANK I TOOL
BANK I TOOL
BANK II TOOL
ALIGNMENT
IMPULSE

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VANOS SOLENOID REPLACEMENT
Refer to TIS repair manual section for com-
plete solenoid replacement procedures.
The solenoids are threaded into the oil distri-
bution flanges through a small opening in the
upper timing case covers.
Special Tool 11 6 420 is required.
VANOS TRANSMISSION RETARD POSI-
TION SET UP TOOLS
Special Tool 11 6 440 is used to rotate the
transmission to the full retard position when
checking the piston position with an ohmme-
ter.
This tool engages the inner hub of the trans-
mission provides an easy method of twisting
it to the left for the ohmmeter test.
Refer to SI Bulletin 04 12 98 for additional
special tool information.
DIAGNOSIS
The VANOS is fully compatible with the diagnostic software providing specific fault codes
and test modules. Additionally, diagnostic requests section provides status of the PWM of
the VANOS solenoids and camshaft position feedback via the camshaft position sensors.
The Service Functions section of the DIS/MoDiC also provides a VANOS system test.
11 6 440
11 6 420

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ENGINE COOLING SYSTEM
The cooling system concepts introduced in
the 1999 Model year including the automatic
transmission heat exchanger and the the
water cooled alternator have been retained
for the X5.
The component locations have however
been changed:
• Thermostat for heat exchanger mounted
directly on radiator
• Transmission heat exchanger - right side
of radiator.

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IHKA SYSTEM AUXILIARY PUMP
The auxiliary water pump for the IHKA is mounted on the left side of the radiator. The func-
tion of the pump remains the same as follows:
• provide adequate coolant flow for IHKA opera-
tion.
• provide coolant circulation for the REST function
of IHKA.

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DME-ME 7.2 ENGINE MANAGEMENT SYSTEM
The “ME” designation identifies the system as “M” = Motronic, “E” = EML.
• Manufactured by Bosch to BMW specifica-
tions
• 134 pin SKE (standard shell construction) con-
trol module located in E box
• Diagnostic communication protocol-KWP2000
• Uses break-out box set (P/N 90 88 6 121 300)
• Integral EML throttle control system
- monitors an interior installed PWG
- actuates an electric throttle valve (EDK)
• Integral Cruise control functionality
- monitors cruise control requests
- monitors brake pedal and clutch switches
- carries out throttle control directly via EDK
• Carries out DSC III torque reduction requests.
• VANOS control
• Integrated altitude sensor
• Integrated temp sensor for monitoring E box
temperatures
• Control of E-box fan
• One touch engine start control
• Oxygen Sensor heating
• Engine overrev & Max speed limitation
• Active Hall sensor for camshaft position monitoring
• Single speed secondary air injection system
• Electrically heated coolant system thermostat
• Longlife spark plugs
• IHKA Auxiliary Fan control
•DM-TL (Diagnostic Module - Tank Leak Diagnosis System)
ME 7.2 LOCATION IN E-BOX
1
(9 pins)2
(24 pins)3
(52 pins)4
(40 pins)5
(9 pins)

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