2004 INFINITI QX56 key

BL-102
AUTOMATIC BACK DOOR SYSTEM
Revision: August 20072004 QX56
System DescriptionEIS002SV
The automatic back door system consists of a one piece unit that combines the back door control unit along
with the back door motor, back door clutch and the back door encoder. The back door latch contains a lock
function that can control the two functions of automatic back door latch closure and electrical opener with a
single motor when you close the back door to the halfway-state.

Back door auto closure
When the back door is closed to the halfway state (half-latch) position, the motor automatically drives to
rotate the latch lever and pull it in from half latched to full latched.

Power back door
With the back door closed, press the power liftgate switch or press the remote keyless entry button, or pull
the back door handle with the back door unlocked, the back door latch motor opens the locking plate and
releases the latch. The back door motor then raises the door to the full open position.
With the back door fully open, press the power liftgate switch, remote keyless entry button or the back
door close switch, the back door motor closes the door to the half-latch state. The back door latch motor
then drives the latch to the full close position.
At the onset of each power open or power close application, the hazard lamps will flash 3 times and the
warning chime will sound 3 times lasting a total of 2 seconds.
OPERATION DESCRIPTION
Power Liftgate Switch Operation (Fully Closed → Fully Open Operation)

When the power liftgate switch is pressed, back door control unit terminal 23 receives the signal.

The back door control unit checks the A/T selector lever (P position) through terminal 18, vehicle speed
through terminal 21, ignition status through terminal 7, glass hatch is closed through terminal 17 and bat-
tery voltage is present through terminal 3.

When the back door control unit receives the signal, if the auto back door operating enable conditions are
met, it sends a 5 volt signal through terminal 6 and grounds terminal 9 to sound the warning chime, sends
a signal to the BCM through terminal 4 to flash the hazard lamps and unlocks the back door latch through
terminal 12.

The back door control unit supplies power to the magnetic clutch and the back door motor and moves the
back door in the open direction. (At this time, it also executes speed control, input reverse, and anti-pinch
detection control.)

When the back door is opened to the full-open position, the full-open position is detected by the encoder,
and the back door control unit switches the back door motor OFF and the magnetic clutch is pulsed and
then turned OFF.

The back door is held in the fully open position by the gas stays.
Remote Keyless Entry Operation (Fully Closed → Fully Open Operation)

When the remote keyless entry button is pressed for at least 0.5 seconds, back door control unit terminal
21 receives the signal.

The back door control unit checks the A/T selector lever (P position) through terminal 18, vehicle speed
through terminal 21, ignition status through terminal 7, glass hatch is closed through terminal 17 and bat-
tery voltage is present through terminal 3.

When the back door control unit receives the signal, if the auto back door operating enable conditions are
met, it sends a 5 volt signal through terminal 6 and grounds terminal 9 to sound the warning chime, sends
a signal to the BCM through terminal 4 to flash the hazard lamps and unlocks the back door latch through
terminal 12.

The back door control unit supplies power to the magnetic clutch and the back door motor and moves the
back door in the open direction. (At this time, it also executes speed control, input reverse, and anti-pinch
detection control.)

When the back door is opened to the full-open position, the full-open position is detected by the encoder,
and the back door control unit switches the back door motor OFF and the magnetic clutch is pulsed and
then turned OFF.

The back door is held in the fully open position by the gas stays.

AUTOMATIC BACK DOOR SYSTEM
BL-103
C
D
E
F
G
H
J
K
L
MA
B
BL
Revision: August 20072004 QX56
Back Door Handle Switch Operation (Fully Closed → Fully Open Operation)

When the back door handle is pulled, back door control unit terminal 26 receives the signal.

The back door control unit checks that the back door is unlocked and checks the A/T selector lever (P
position) through terminal 18, vehicle speed through terminal 21, ignition status through terminal 7, glass
hatch is closed, battery voltage and back door close switch position through terminal 13.

When the back door control unit receives the signal, if all auto back door operating enable conditions are
met, it sends a 5 volt signal through terminal 6 and grounds terminal 9 to sound the warning chime, sends
a signal to the BCM through terminal 4 to flash the hazard lamps and unlocks the back door latch through
terminal 12.

The back door control unit supplies power to the magnetic clutch and the back door motor and moves the
back door in the open direction. (At this time, it also executes speed control, input reverse, and anti-pinch
detection control.)

When the back door is opened to the full-open position, the full-open position is detected by the encoder,
and the back door control unit switches the back door motor OFF and the magnetic clutch is pulsed and
then turned OFF.

The back door is held in the fully open position by the gas stays.
Power Liftgate Switch Operation (Fully Open → Fully Closed Operation)

When the power liftgate switch is pressed, the back door control unit terminal 23 receives the signal.

The back door control units checks door position through the rotary encoder.

When the back door control unit receives the signal, if the auto back door operating enable conditions are
met, it sends a signal through terminal 6 and grounds terminal 9 to sound the warning chime and sends a
signal to the BCM through terminal 4 to flash the hazard lamps.

The back door control unit supplies power to the magnetic clutch and the back door motor and move the
back door in the close direction. (At this time, it also executes speed control, input reverse, and anti-pinch
detection control.)

When the back door reaches the half-latch state, the half-latch switch detects this and the signal is sent to
the back door control unit terminal 22.

When the back door control unit receives the half latch switch signal, it switches OFF the back door motor
and the magnetic clutch and operates the cinch latch motor.

When the back door latch operates and full close is detected through terminal 14 of the back door control
unit, the cinch latch motor reverses to the neutral position and the back door auto closure operation ends
and the door is fully closed.
Remote Keyless Entry Operation (Fully Open → Fully Closed Operation)

When the remote keyless entry switch is pressed for at least 0.5 seconds, the back door control unit termi-
nal 21 receives the signal.

The back door control units checks door position through the rotary encoder.

When the back door control unit receives the signal, if the auto back door operating enable conditions are
met, it sends a signal through terminal 6 and grounds terminal 9 to sound the warning chime and sends a
signal to the BCM through terminal 4 to flash the hazard lamps.

The back door control unit supplies power to the magnetic clutch and the back door motor and move the
back door in the close direction. (At this time, it also executes speed control, input reverse, and anti-pinch
detection control.)

When the back door reaches the half-latch state, the half-latch switch detects this and the signal is sent to
the back door control unit terminal 22.

When the back door control unit receives the half latch switch signal, it switches OFF the back door motor
and the magnetic clutch and operates the cinch latch motor.

When the back door latch operates and full close is detected through terminal 14 of the back door control
unit, the cinch latch motor reverses to the neutral position and the back door auto closure operation ends
and the door is fully closed.

BL-104
AUTOMATIC BACK DOOR SYSTEM
Revision: August 20072004 QX56
Back Door Close Switch Operation (Fully Open → Fully Closed Operation)

When the back door close switch is pressed, the back door control unit terminal 8 receives the signal.

The back door control units checks back door disable switch terminal 13 status and door position (must be
fully opened), through rotary encoder and battery voltage.

When the back door control unit receives the signal, if the auto back door operating enable conditions are
met, it sends a signal through terminal 6 and grounds terminal 9 to sound the warning chime and sends a
signal to the BCM through terminal 4 to flash the hazard lamps.

The back door control unit supplies power to the magnetic clutch and the back door motor and move the
back door in the close direction. (At this time, it also executes speed control, input reverse, and anti-pinch
detection control.)

When the back door reaches the half-latch state, the half-latch switch detects this and the signal is sent to
the back door control unit terminal 22.

When the back door control unit receives the half latch switch signal, it switches OFF the back door motor
and the magnetic clutch and operates the cinch latch motor.

When the back door latch operates and full close is detected through terminal 14 of the back door control
unit, the cinch latch motor reverses to the neutral position and the back door auto closure operation ends
and the door is fully closed.
Reversal

If the power liftgate switch, remote keyless entry switch or the back door close switch is pressed during
back door power open and close operation, the back door will reverse direction.

If the outside handle switch is pulled during power open or power close, the power back door will automat-
ically stop and go to manual mode.
Anti-Pinch Function

During auto open or close operation, if an object is detected in the door's path, the back door operates in
the reverse direction until fully closed or open to prevent pinching.

During auto close operation, if an object is detected by the pinch strips in the door's path, the back door
operates in the open direction until it is fully open.

During auto cinch latch operation, if an object is detected by the pinch strips in the door's path, the back
door operates depending on the back door disable switch position. If the back door disable switch is in the
OFF position, the back door operates in the open direction until it is fully open. If the back door disable
switch is in the ON position, the back door will reverse only until the latch is fully released.

If the pinch strips are present but are not functioning properly (permanently sensing a pinch), the auto-
matic back door system will operate in the open direction only.

If the pinch strips are not connected to the automatic back door system, it will not operate.
Gas Stay Check

During each power open operation, the back door control unit monitors motor current draw to determine if
the gas stays are functioning properly.

If a failure of the gas stays is detected, the back door control unit will close the back door while sounding
the warning chime.
Warning Functions

The warning chime is sounded according to the back door operating state, operations, and conditions.

AUTOMATIC BACK DOOR SYSTEM
BL-105
C
D
E
F
G
H
J
K
L
MA
B
BL
Revision: August 20072004 QX56
Auto Back Door Operation Enable Conditions
Control When Operating Enable Conditions Not Met During Power Open/Close
Control When Operating Enable Conditions No Longer Met
Operation Power liftgate switch Remote keyless entry Back door handle switchBack door
close switch
Operating
directionFully closed →
openFully open →
closedFully closed →
openFully open
→ closedFully closed →
openFully open →
closedFully open →
closed
Disable
switchON or OFF OFF OFF
Vehicle stop
conditionA/T selector
lever in P or N
range and vehi-
cle speed less
than 2 km/h or
ignition switch
in OFF position—A/T selector
lever in P or N
range and vehi-
cle speed less
than 2 km/h or
ignition switch
in OFF position—A/T selector
lever in P or N
range and vehi-
cle speed less
than 2 km/h or
ignition switch
in OFF position——
Battery volt-
ageApprox. 11V or more
Back door
lock status— — — — Unlocked — —
Glass hatch Closed
Items Operation condition Not met case Control
A/T selector lever P positionP or N position with ignition ON
or any position with ignition
OFFOtherContinue power open or close,
but sounds warning chime.
Back door disable switch OFF ON
Cancels power open/close
operation or door will release to
manual mode. Voltage drop 11V or more11 > V > 9
9 > V > reset voltage
Reset voltage > V No power function available
Handle switch Normal (GND) Error (OPEN)No operation. Cancel power
open/close release to manual.
Glass hatch Closed OFFCancels power door open oper-
ation, door will release to man-
ual mode.
Description Operation Control
Back door disable switch turned ONWarning chime active
→ Shift to manual mode after full open or
close operation is complete
(Recovery to power mode when main
switch turned OFF or door fully closed)→ Shift to manual mode
A/T selector lever P or N position with igni-
tion switch ONWarning chime active and one-way opera-
tion continuous
(Warning chime inactive and door fully
open or fully closed or operating conditions
recovered)Full open: power close operation allowed
Full close: operating conditions not met →
no power open function.
Voltage drop 11 - 9VOne-way operation continued (equivalent
to the case of starting voltage ← 11V for
handle operation with warning chime
active)Not allowed
Voltage drop less than 9V
(Microcomputer reset voltage - clutch hold
voltage)

Motor stopped

Clutch may slip

Control not possible because microcom-
puter being resetControl not possible because microcom-
puter being reset

BL-106
AUTOMATIC BACK DOOR SYSTEM
Revision: August 20072004 QX56
Warning Chime Active Conditions
The warning chime uses two types of audio warnings, a friendly chime and a warning chime. The friendly
chime consists of dings lasting 0.66 seconds each immediately followed by the next ding. The warning chime
consists of beeps lasting 0.33 seconds with a pause of 0.33 seconds between each beep.
Reverse Conditions
Operation status Operation or conditions Warning chime pattern
When auto operation startsPower liftgate switch operation
Friendly chime
2 seconds, 3 dings Remote keyless entry operation
Back door handle switch operation
Back door close switch operation
When reverse operation startsWhen reverse request is detected from
power liftgate switch, remote keyless
entry or back door close switchFriendly chime
1.3 seconds, 2 dings
When obstacle is detectedWarning chime
2 seconds, 3 beeps
Operating at low voltage While opening or closing Warning chime
2 seconds, 3 beeps
A/T selector lever not in P positionBack door close operationFriendly chime
Continuously dings
Back door open operationWarning chime
Continuously beeps
(until close operation is started)
Type Overload reverse
Operation covered Both directions
Detection methodOperation speed and motor current change direction
Pinch strips during back door close operation
Non-reversed area

For about 0.5 seconds immediately after drive motor operation
starts

Between full open and approx. 7° from full open

Closure operation area (half switch - close switch)
Number of times reverse allowedOne reversal is allowed (if a second obstacle is detected during a
power open or close operation, the door reverts to manual
mode).

AUTOMATIC BACK DOOR SYSTEM
BL-115
C
D
E
F
G
H
J
K
L
MA
B
BL
Revision: August 20072004 QX56
Trouble Diagnosis ProcedureEIS002T0
1. Check the symptom and customer's requests.
2. Understand outline of system. Refer to BL-45, "
System Description" .
3. Confirm system operation.
4. Perform self-diagnosis procedures. Refer to BL-115, "
Self-Diagnosis Procedures" .
5. Refer to diagnosis chart by symptom, repair or replace any malfunctioning parts. Refer to BL-116, "
Diag-
nosis Chart" .
6. Inspection End.
Self-Diagnosis ProceduresEIS005X4
INPUT SIGNAL CHECK MODE
Input signal check mode allows testing of switch input signal to the back door control unit.
To activate input signal check mode on the automatic back door, perform the following steps:
1. Turn ignition switch OFF.
2. Turn back door close switch to CANCEL (system cancelled).
3. Place A/T selector lever in P position.
4. Using the inside emergency release lever, open the back door.
5. Have an assistant press and hold the back door handle switch.
6. While the assistant continues to hold the back door handle switch, turn ignition switch ON (DO NOT start
engine).
7. After approximately 5 seconds, the back door warning chime will sound for 0.5 seconds.
8. Release the back door handle switch.
9. Within 8 seconds of the back door warning chime sounding, press and hold the power liftgate switch.
10. After approximately 5 seconds, the back door warning chime will sound for 1 second.
11. Release the power liftgate switch.
12. The input signal check mode is now initialized.
The input signal check mode can test the following inputs. The back door warning chime will sound for approx-
imately 0.5 seconds each time a switch signal input occurs. Use this test when one of these inputs is not
responding during normal automatic back door operation.
*Back door warning chime should sound as soon as vehicle moves.
Turn ignition switch OFF to end input signal check mode.
OPERATING CHECK MODE
Operating check mode allows self-diagnosis of the automatic back door system.
To activate operating check mode on the automatic back door, perform the following steps:
1. Turn ignition switch OFF.
2. Turn back door close switch to CANCEL (system cancelled).
3. Place A/T selector lever in P position.
Switch signal Operation Refer to
Power liftgate switch OFF → ONBL-118
Back door close switch (CLOSE) OFF → ONBL-120
Back door close switch (CANCEL) OFF → ONBL-121
Back door handle switch OFF → ONBL-127
Glass switch OFF → ONBL-36
A/T device (park switch) P position → other than P positionAT- 1 9 1
Vehicle speed* Vehicle speedAT-6 8
Remote keyless entry signal Keyfob switch OFF → ONBL-66
Door lock/unlock signal LOCK → UNLOCKBL-34
Pinch strip LH signal OFF → ONBL-122
Pinch strip RH signal OFF → ONBL-122

AUTOMATIC BACK DOOR SYSTEM
BL-117
C
D
E
F
G
H
J
K
L
MA
B
BL
Revision: August 20072004 QX56
Back Door Power Supply and Ground Circuit InspectionEIS002T2
1. BACK DOOR POWER SUPPLY CIRCUIT INSPECTION
1. Turn ignition switch OFF.
2. Disconnect back door control unit.
3. Check voltage between back door control unit connector B55
terminals 3, 10 and ground.
OK or NG
OK >> GO TO 2.
NG >> Repair or replace harness.
2. BACK DOOR GROUND CIRCUIT INSPECTION
Check continuity between back door control unit connector B55 ter-
minal 1, 2 and ground.
OK or NG
OK >> Circuit is OK.
NG >> Repair or replace harness.
During auto closing operations, if obstruction is detected, the
door does not operate in reverse.Back door motor assembly —
During close or cinch operations, the door does not operate in
reverse if the back door handle is operated.Handle switch systemBL-127
When the keyfob is operated, the back door does not operate
automatically.Remote keyless entry system inspectionBL-44Power window serial linkBL-114
Pinch strip system inspectionBL-122
Auto closure does not operate.Half-latch switch systemBL-124Cinch latch motor systemBL-128
Handle switch systemBL-127
The back door does not open.
(Closure motor rotation is not reversed.)Open switch systemBL-125
Handle switch systemBL-127
Warning chime does not sound. Back door warning chime systemBL-123
Auto closure operation works, but the back door is not fully
closedClose switch systemBL-126Handle switch systemBL-127
Cinch latch motor systemBL-128
Back door latch assembly mechanism dam-
aged or worn.— Symptom Suspect systems Refer to
3 (Y/R) - Ground : Approx. battery voltage
10 (L/B) - Ground : Approx. battery voltage
WIIA0567E
1 (B) - Ground : Continuity should exist.
2 (B) - Ground : Continuity should exist.
LIIA0801E

BL-132
FRONT DOOR LOCK
Revision: August 20072004 QX56
FRONT DOOR LOCKPFP:80502
Component StructureEIS002TF
Removal and InstallationEIS006BK
REMOVAL
1. Remove the front door glass regulator. Refer to GW-70, "FRONT DOOR GLASS REGULATOR" .
2. Remove the front door window rear glass run.
3. Remove the door side grommet, and the bolt (TORX T30) from
the grommet hole.
4. While pulling the outside handle, remove the door key cylinder
assembly or escutcheon.
1. Grommet 2. Front door striker 3. Door lock assembly
4. Outside handle cable 5. Inside handle assembly 6. Inside handle cable
7. Door lock cable 8. Key cylinder rod (Driver side only) 9. Door lock cylinder
10. Outside handle bracket 11. Front gasket 12. Outside handle
13. Door key cylinder escutcheon
(Driver side) Outside handle
escutcheon (Passenger side)14. Rear gasket
LIIA1728E
Torx bolt 5.3 N·m (0.54 kg-m, 47 in-lb)
PIIA3553E
PIIA3554E