ignition INFINITI QX56 2006 Factory Service Manual

AUTOMATIC BACK DOOR SYSTEMBL-101
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Revision: November 2009 2006 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 keyfob is pressed for at least 0.5 seconds, the back door control unit terminal 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.

AUTOMATIC BACK DOOR SYSTEMBL-103
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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 switchRemote keyless entry Back door handle switch Back door
close switch
Operating direction Fully closed
→
open Fully open
→
closed Fully closed
→
open Fully open
→ closed Fully closed
→
open Fully open
→
closed Fully open
→
closed
Close
switch CANCEL or NEUTRAL
NEUTRALNEUTRAL
Vehicle stop
condition 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 —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-
age Approx. 11V or more
Back door
lock status ————
Unlocked——
Glass hatch Closed
ItemsOperation condition Not met caseControl
A/T selector lever P position P or N position with ignition ON
or any position with ignition
OFFOther
Continue power open or close,
but sounds warning chime.
Back door close switch NEUTRAL CANCEL
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 ClosedOFF Cancels power door open oper-
ation, door will release to man-
ual mode.
Description
Operation Control
Back door close switch turned to CANCEL Warning 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 ON Warning 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 - 9V One-way operation continued (equivalent
to the case of starting voltage
← 11 V f o r
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 reset Control not possible because microcom-
puter being reset

AUTOMATIC BACK DOOR SYSTEMBL-111
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Terminals and Reference Value for Back Door Control UnitEIS00610
Te r m i n a l Wire
Color Item
Condition Voltage (V)
(Approx.)
1 B Ground ——
2 B Ground ——
3 Y/R Battery power supply —Battery voltage
4 G Hazard lamp output Request to flash hazardsPulse must be >50ms
but less than 250ms
5 B/P Pinch strip ground ——
6 R Warning chime output Back door motor activeBattery voltage
7 G/R Ignition switch Ignition switch ON
Battery voltage
Ignition switch OFF 0
8 GR/B Back door close switch CLOSE position (ON)
0
NEUTRAL position (OFF) Battery voltage
9 L Warning chime ground ——
10 L/B Battery power supply —Battery voltage
11 YCinch latch motor
CLOSE output
Back door close operation
Battery voltage
12 L Closure motor
RETURN output Back door release operation
Battery voltage
13 P/L Back door close switch CANCEL position
0
NEUTRAL position 5
14 P Close switch signal While fully opening back door
15 O/L Open switch signal While fully closing back door
17 GR Glass hatch ajar signal Glass hatch OPEN
0
Glass hatch CLOSED 5
18 GR/R Park switch P or N position (Ignition is ON)
0
Other (Ignition is ON) 9
19 BR/B Pinch strip RH Detecting obstruction
0
Other 5
20 V/G Pinch strip LH Detecting obstruction
0
Other 5
PIIA3278E
WIIA1047E
WIIA1047E

AUTOMATIC BACK DOOR SYSTEMBL-113
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Trouble Diagnosis ProcedureEIS00612
1. Check the trouble 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-113, "
Self-Diagnosis Procedures" .
5. Refer to diagnosis chart by symptom, repair or replace any malfunctioning parts. Refer to BL-114, "
Diag-
nosis Chart" .
6. Inspection End.
Self-Diagnosis ProceduresEIS00613
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 OperationRefer to
Power liftgate switch OFF → ON BL-116
Back door close switch (CLOSE) OFF → ON BL-118
Back door close switch (CANCEL) OFF → ON BL-119
Back door handle switch OFF → ON BL-125
Glass switch OFF → ON BL-117
A/T device (park switch) P position → other than P position AT- 6 1
Vehicle speed* Vehicle speed—
Remote keyless entry signal Keyfob switch OFF → ON BL-44
Door lock/unlock signal LOCK → UNLOCK BL-16
Pinch strip LH signal OFF → ON BL-121
Pinch strip RH signal OFF → ON BL-121

BL-114
AUTOMATIC BACK DOOR SYSTEM
Revision: November 20092006 QX56
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 the power liftgate switch 5 times in rapid succession.
10. After approximately 5 seconds, the back door warning chime will sound for 1 second.
11. Release the power liftgate switch.
12. Immediately close the back door manually.
13. Press and release the power liftgate switch to activate operating check mode.
Self-diagnosis results are indicated by the back door warning chime.
Turn ignition switch OFF to end input signal check mode.
Diagnosis ChartEIS00614
Back door warning chime order Back door warning chime length
Start self-diagnosis 1.5 seconds
OK NG
1. Operating conditions diagnosis 0.5 seconds0.2 seconds
2. Back door encoder diagnosis 0.5 seconds0.2 seconds
3. Back door clutch diagnosis 0.5 seconds0.2 seconds
4. Back door motor diagnosis 0.5 seconds0.2 seconds
5. Cinch latch motor diagnosis 0.5 seconds0.2 seconds
Restart self-diagnosis 1.5 seconds
ItemNG ResultRefer to
1. Operating conditions diagnosis result One of the following operating conditions no
longer met: ignition switch ON, back door
close switch (CANCEL) ON, A/T selector lever
in P position—
2. Back door encoder diagnosis result Sensor diagnosis/short, pulse signal, pulse
signal directionBL-135
3. Back door clutch diagnosis result
Back door clutch does not operateBL-135
4. Back door motor diagnosis result Back door motor does not operate (no operat-
ing current)BL-135
5. Cinch latch motor diagnosis result Cinch latch motor does not operate (no oper-
ating current)
BL-135
Symptom
Suspect systemsRefer to
Automatic operations are not executed from the back door fully
closed or fully open position.
(Auto closure operates normally.) Power liftgate switch system inspection
BL-116
Park switch —
Power window serial link BL-112
Pinch strip system inspectionBL-121
Automatic operations are not carried out together with open/close
operations.
(Manual operations are normal.) Power liftgate switch system inspection
BL-116Back door close switch system inspectionBL-118
Auto back door power supply and ground cir-
cuit system inspection.BL-115
The auto closure function does not operate.
(Stops at the halfway position for auto closing operations.) Pinch strip system inspection
BL-121

AUTOMATIC BACK DOOR SYSTEMBL-115
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Back Door Power Supply and Ground Circuit InspectionEIS00615
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 system
BL-125
When the keyfob is operated, the back door does not operate
automatically. Remote keyless entry system inspection
BL-44Power window serial linkBL-112
Pinch strip system inspectionBL-121
Auto closure does not operate. Half-latch switch system
BL-122Cinch latch motor systemBL-126
Handle switch systemBL-125
The back door does not open.
(Closure motor rotation is not reversed.) Open switch system
BL-123
Handle switch systemBL-125
Warning chime does not sound. Back door warning chime systemBL-122
Auto closure operation works, but the back door is not fully
closed Close switch system
BL-124Handle switch systemBL-125
Cinch latch motor systemBL-126
Back door latch assembly mechanism dam-
aged or worn. —
Symptom
Suspect systemsRefer to
3 - Ground: Approx. battery voltage
10 - Ground : Approx. battery voltage
WIIA0567E
1 - Ground: Continuity should exist.
2 - Ground : Continuity should exist.
LIIA0801E

BL-116
AUTOMATIC BACK DOOR SYSTEM
Revision: November 20092006 QX56
Power Liftgate Switch System InspectionEIS00616
1. POWER LIFTGATE SWITCH FUNCTION INSPECTION
Check power liftgate switch using switch operation.
OK or NG
OK >> Power liftgate switch is OK.
NG >> GO TO 2.
2. POWER LIFTGATE SWITCH POWER SUPPLY CIRCUIT INSPECTION
1. Turn ignition switch OFF.
2. Check voltage between power liftgate switch connector M92 ter- minal 1 and ground.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace harness.
3. POWER LIFTGATE SWITCH SIGNAL INSPECTION
1. Turn ignition switch OFF.
2. While operating the power liftgate switch, check voltage between back door control unit connector B55 terminal 23 and
ground.
OK or NG
OK >> Switch is OK.
NG >> GO TO 4.
4. POWER LIFTGATE SWITCH CIRCUIT INSPECTION
1. Disconnect power liftgate switch and back door control unit connector.
2. Check continuity between power liftgate switch connector M92 terminal 1 and back door control unit connector B55 terminal 23.
OK or NG
OK >> GO TO 5.
NG >> Repair or replace harness. 1 - Ground
:Approx. battery voltage
LIIA1551E
Terminals
ConditionVoltage (V)
(Approx.)
(+) (-)
23 GroundPower liftgate
switch ON
0
OFF 5
LIIA0802E
1 - 23 : Continuity should exist.
LIIA1064E

BL-118
AUTOMATIC BACK DOOR SYSTEM
Revision: November 20092006 QX56
2. CHECK GLASS HATCH AJAR SWITCH CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect glass hatch ajar switch, BCM and back door control unit.
3. Check continuity between glass hatch ajar switch connector D707 terminal + and BCM connector M19 ter- minal 42.
4. Check continuity between glass hatch ajar switch connector D707 terminal + and back door control unit connector B55 termi-
nal 17.
5. Check continuity between glass hatch ajar switch connector D707 terminal + and ground.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace harness.
3. CHECK GLASS HATCH AJAR SWITCH
1. Disconnect glass hatch ajar switch connector.
2. Check continuity between glass hatch ajar switch connector terminal and ground.
OK or NG
OK >> Check glass hatch ajar switch case ground condition.
NG >> Replace glass hatch ajar switch, or repair or replace harness.
Back Door Close (Close) Switch System InspectionEIS00617
1. BACK DOOR CLOSE SWITCH FUNCTION INSPECTION
Check back door close (close) switch using switch operation.
OK or NG
OK >> Back door close switch is OK.
NG >> GO TO 2. + - 42
: Continuity should exist
+ - 17 : Continuity should exist
+ - Ground : Continuity should not exist
LIIA1547E
Terminals Condition Continuity
Glass hatch ajar switch +
– Ground Open
Yes
Closed No
LIIA1151E

AUTOMATIC BACK DOOR SYSTEMBL-119
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2. BACK DOOR CLOSE SWITCH SIGNAL INSPECTION
1. Turn ignition switch OFF.
2. While operating the back door close switch, check voltage between back door control unit connector B55 terminal 8 and
ground.
OK or NG
OK >> Back door close switch is OK.
NG >> GO TO 3.
3. BACK DOOR CLOSE SWITCH CIRCUIT INSPECTION
1. Disconnect back door close switch and back door control unit connector.
2. Check continuity between back door close switch connector B63 terminal 1 and back door control unit connector B55 terminal 8.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace harness.
4. BACK DOOR CLOSE SWITCH GROUND INSPECTION
Check continuity between back door close switch connector B63 ter-
minal 3 and ground.
OK or NG
OK >> Replace the back door close switch.
NG >> Repair or replace harness.
Back Door Close (Cancel) Switch System InspectionEIS00618
1. BACK DOOR CLOSE SWITCH FUNCTION INSPECTION
Check back door close (cancel) switch using switch operation.
OK or NG
OK >> Back door close switch is OK.
NG >> GO TO 2.
Te r m i n a l s ConditionVoltage (V)
(Approx.)
(+) (-)
8 Ground Back door
close
switch ON 0
OFF Battery voltage
LIIA0805E
1 - 8 : Continuity should exist.
LIIA1066E
3 - Ground: Continuity should exist.
WIIA0602E

BL-120
AUTOMATIC BACK DOOR SYSTEM
Revision: November 20092006 QX56
2. BACK DOOR CLOSE (CANCEL) SWITCH SIGNAL INSPECTION
1. Turn ignition switch OFF.
2. While operating the back door close (cancel) switch, check volt- age between back door control unit connector B55 terminal 13
and ground.
OK or NG
OK >> Back door close switch is OK.
NG >> GO TO 3.
3. BACK DOOR CLOSE (CANCEL) SWITCH CIRCUIT INSPECTION
1. Disconnect back door close switch and back door control unit connector.
2. Check continuity between back door close switch connector B63 terminal 5 and back door control unit connector B55 terminal 13.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace harness.
4. BACK DOOR CLOSE SWITCH GROUND INSPECTION
Check continuity between back door close switch connector B63 ter-
minal 3 and ground.
OK or NG
OK >> Replace the back door close switch.
NG >> Repair or replace harness.
Terminals ConditionVoltage (V)
(Approx.)
(+) (-)
13 Ground Back door
close switch ON
0
OFF 5
LIIA1068E
5 - 13 : Continuity should exist.
LIIA1069E
3 - Ground: Continuity should exist.
WIIA0602E