1993 BMW 318I CONVERTIBLE trunk

E36 AUTOMATIC ELECTRO MECHANICAL (EM)
CONVERTIBLE TOPS
The Automatic EM convertible top was introduced as a“Semi”Automatic in the 1994
model year. The top was upgraded to a fully automatic top in 1997. Except for a few addi-
tional components and an additional function on the fully automatic version, both systems
function the same. For this reason the systems are described simultaneously and high-
lighted as required where differences occur.
FEATURES
The top is designed as a self tensioning, electric mechanical power operated folding top.
The main features include:
BOTH VERSIONS:
• Electrical interlock of the trunk lid when the top storage cover is unlocked or open.
 Automatic partial lowering of the four side windows when lowering or raising the top.
 Automatic full raising of all four windows once top is stored in the storage compartment.
 Fully diagnosible EM Top Control Module.
 A textile, crease free interior liner clipped to the top frame.
 Emergency release handle inside the passenger compartment, for manually raising the
top with an electrical failure.
 A removable (zipper) green tinted plastic rear window.
 Soft top material of 3-ply with 40% cotton fabric lining and 100% Arcyl outer skin.
SEMI AUTO ONLY:
 A centrally located turn lock fastener on the for-
ward edge of the top for locking and unlocking
the top to the windshield frame.
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MOTORS:
•Top drive motor (A) with gear assembly and position micro switches (S1 & S2). The top
drive motor is located under the top storage compartment on the left side of the trunk.
•Top storage cover motor (B) with drive linkage and an integrated hall sensor. The cover
motor is located in the trunk on the left side behind the trim cover.
•FULL AUTO ONLY:Top Lock Motor with flexible drive tubes and lock drive mecha-
nisms. The lock drive mechanisms also activate the off tension linkage rods for auto-
matically moving the top to the off tension position.
TOP LOCK MOTOR TOP LOCK MOTOR
FLEXIBLE DRIVE TUBES FLEXIBLE DRIVE TUBES
OFF TENSION LINKAGE RODS OFF TENSION LINKAGE RODS
LEFT LOCK/DRIVE LEFT LOCK/DRIVERIGHT LOCK/DRIVE RIGHT LOCK/DRIVE

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S5 - Identified as Trunk Lid Microswitch in the ETM (Not Adjustable)
•Located on Trunk Lock. Prevents convertible
top operation when trunk is open.
•S5 is also used on fully manual top. It provides a ground for the convertible top stor-
age lid lock motor. This is a unique component only found on the manual top system
which electrically prevents the storage lid from being opened manually when the trunk
lid is opened.
•S5 utilization on the automatic top system provides a ground signal to the control mod-
ule when the trunk is open. The control module cancels any top operation when this
ground signal is present.
S6 - Identified as Convertible Top Storage Lid Microswitch in the ETM (Adjustable)
•Located on Right Side Storage Cover Lock
Latch
•Signal is input to ZKE IV General Module.
•Low signal indicates convertible top storage
cover is open. Trunk can not be opened.
S7 - FULLY AUTOMATIC TOP ONLY: Identified as Position Microswitch Locking in
the ETM (Not Adjustable)
•Located on Top Lock Drive Assembly.
•Open anytime top is not locked to windshield
frame.
•Closed when top is locked to windshield frame.
S8 - FULLY AUTOMATIC TOP ONLY: Identified as Position Microswitch Unlocking
in the ETM (Not Adjustable)
•Located on Top Lock Drive Assembly.
•Closed only when the top lock motor is driven to
the fully unlocked position.
•Open all other times.
S7 S7S8 S8

OPERATION
The following prerequisites must be met for the top to function:
Trunk Lid Closed- Electrical interlock of the trunk and top. Due to the design of the top
storage cover and trunk lid, damage to the cover or lid would occur if both were open at
the same time.
Ignition key switched on KL R, (preferably engine running to prevent unnecessary bat-
tery drain)
Vehicle stopped(speed “A” signal <3 MPH)
Roll over bars retracted (if equipped) - bars interfere with the top operation as it is low-
ering into the storage compartment.
LOWERING THE TOP
•SEMI AUTOMATIC TOP ONLY - Unlock the top with the turn lock fastener and push
the top over the tension point.S4 must close for the top to operate. Press and hold
the top switch.Go to “TENSION BAR RAISED” on next page.
•FULLY AUTOMATIC TOP ONLY -Press and hold the top switch. All Side windows
lower automatically regardless of their position, by a signal from the top module to the
General Module (ZKE IV).
1. The top lock motor is powered in the unlock direction.
2. The left and right side locks are mechanically released via the drive cables.
3. Microswitch S7 opens indicating the top is unlatched from the windshield frame.
4. Once the locks are completely released, the top lock motor continues to run lifting
the front bow above the tension point via the tension rods.
5. As the front bow passes the tension point, micro switch S8 closes. The top lock
motor switches off and the top motor is switched ON.
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TENSION BAR RAISED
At the same time the windows are lowering, the top drive motor is switched on and the ten-
sion bar is raised to a vertical position. The drive lever of the top linkage rotates counter
clockwise to push the tension bar to a raised position.
The control module recognizes the raising of the tension bar by the closed contacts of
micro switch S1 in the motor assembly.
When the tension bar has raised to the full vertical position micro switch S2 closes and the
motor is switched off.
STORAGE COVER OPENED
The top storage cover motor is switched on and turns counter-clockwise. This action
releases the locks of the cover via the bowden cables. The locks are forced out of the
clamps by spring pressure.
The drive linkage continues to push the cover to a raised position. A hall sensor integrat-
ed in the cover motor provides status of the storage lid movement and position to the CVM.
The motor is switched off when it reaches the end of its predetermined travel.
S6 also closes the moment the storage cover is released from its locked position. The sig-
nal is provided the GM to prevent the trunk from opening.

RE-CONNECTING DRIVE MOTORS
Due to the interlock of the trunk lid an unlocked top storage cover, the following procedure
must be followed to reconnect the top drive motors, to restore electrical operation:
•Lower all the side windows with the central switch
•Unlock the top from the windshield frame, raise it over the tension point and open the
storage cover.
•Lower the top into the storage compartment and close the storage cover.
•Disconnect fuse #7 in the front power distribution box (this will override the forced lock-
ing of the trunk).
•Open the trunk lid and remove the trim cover from the left side of the trunk.
•Reconnect the motors with the gear drives. The actuating rods can be moved slightly
to allow the gear teeth to engage.
•Close trunk lid and reinstall fuse #7.
•The EM top system must now be initialized to restore normal operation.
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Z3 ELECTRO HYDRAULIC TOP COMPONENTS
The system components include:
•Electric motor/pump with reservoir
and relays,
•Hydraulic tubing,
•Hydraulic cylinder with piston,
•“Off tension” microswitch
•Console mounted switch
Located in the driver’s side B pillar, the
hydraulic piston connects to the body by
a clip and the top frame by a ball pin.
The electric motor/ hydraulic pump
assembly is in the left rear corner of the
trunk. The hydraulic tubing runs through
an opening in the trunk bulkhead to the
hydraulic piston.
The “see thru” reservoir of the pump has
“min/max” fill lines which allows quick visu-
al confirmation of the system fluid level.
Use hydraulic oil from kit P/N: 54 34 8 410
308.
Emergency Valve:The hydraulic unit has
an Emergency Valve located on its top sur-
face.
If the top can not be operated due to an elec-
trical or hydraulic fault, the valve is
unscrewed 1/2 turn allowing the top to be
raised manually.
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HYDRAULIC
FILLER PLUG
HYDRAULIC
HOSE ROUTING
RUBBER
ISOLATION
MOUNTS
AND
BRACKETS
“EMERGENCY”
VALVERESERVOIR
TRUNK MOUNTED
ELECTRIC MOTOR/
HYDRAULIC PUMP
FLEXIBLE
HYDRAULIC
TUBE
HYDRAULIC
CYLINDER/
PISTON
SYSTEM
CONNECTOR
OFF TENSION
MICROSWITCH