ignition INFINITI QX56 2004 Factory Service Manual
Page 863 of 3371
BL-98
VEHICLE SECURITY (THEFT WARNING) SYSTEM
Revision: August 20072004 QX56
3. CHECK HARNESS CONTINUITY
1. Turn ignition switch OFF.
2. Disconnect BCM and combination meter (security indicator lamp).
3. Check continuity between BCM connector (A) M18 terminal 23
and combination meter (security indicator lamp) harness con-
nector (B) M24 terminal 28.
4. Check continuity between BCM connector (A) M18 terminal 23
and ground.
OK or NG
OK >> Check the following:
10A fuse [No. 19, located in fuse block (J/B)]
Harness for open or short between combination meter (security indicator lamp) and fuse
NG >> Repair or replace harness.
Front Door Lock Assembly LH (Key Cylinder Switch) CheckEIS002SQ
1. CHECK FRONT DOOR LOCK ASSEMBLY LH (KEY CYLINDER SWITCH)
With CONSULT-II
Check front door lock assembly LH (key cylinder switch) ("KEY CYL LK-SW") and ("KEY CYL UN-SW) in
DATA MONITOR mode in CONSULT–II.Refer to BL-27, "
DATA MONITOR" .
When key inserted in front key cylinder is turned to LOCK:
When key inserted in front key cylinder is turned to UNLOCK:
Without CONSULT-II
Check voltage between main power window and door lock/unlock switch connector D7 terminals 4, 6 and
ground.
OK or NG
OK >> Front door lock assembly LH (key cylinder switch) signal is OK.
NG >> GO TO 2.23 (G/O) - 28 (G/O) : Continuity should exist.
23 (G/O) - ground : Continuity should not exist.
LIIA2253E
KEY CYL LK-SW : ON
KEY CYL UN-SW : ON
LIIA0188E
Connec-
torTerminals (Wire
color)Condition of key cylinder
switchVoltage (V)
(Approx.)
( + ) ( – )
D74 (L)
GroundNeutral/Unlock 5
Lock 0
6 (R)Neutral/Lock 5
Unlock 0
LIIA0566E
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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.
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AUTOMATIC BACK DOOR SYSTEM
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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.
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AUTOMATIC BACK DOOR SYSTEM
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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 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
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AUTOMATIC BACK DOOR SYSTEM
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Terminals and Reference Value for Back Door Control UnitEIS002SY
Te r m i n a l Wire
ColorItem ConditionVoltage (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 active Battery voltage
7 G/R Ignition switchIgnition switch ON Battery voltage
Ignition switch OFF 0
8 GR/B Back door close switchBack door close switch ON 0
Back door close switch OFF 5
9 L Warning chime ground — —
10 W/L Battery power supply — Battery voltage
11 YCinch latch motor
CLOSE outputBack door close operation Battery voltage
12 LClosure motor
RETURN outputBack door release operation Battery voltage
13 P/L Back door cancel switchBack door cancel switch ON 0
Back door cancel switch OFF 5
14 P Close switch signal Back door close status 5
15 O/L Open switch signal Back door open status 5
17 GR Glass hatch ajar signalGlass hatch OPEN 0
Glass hatch CLOSED 5
18 GR/R Park switchP or N position (Ignition is ON) 0
Other (Ignition is ON) 5
19 BR/B Pinch strip RHDetecting obstruction 0
Other 5
20 V/G Pinch strip LHDetecting obstruction 0
Other 5
21 W/V Power window serial link —
22 BR Half switch signal Back door half latch position 0
23 L/W Power liftgate switchON 0
OFF 5
PIIA3278E
PIIA2344E
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AUTOMATIC BACK DOOR SYSTEM
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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
Page 881 of 3371
BL-116
AUTOMATIC BACK DOOR SYSTEM
Revision: August 20072004 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 ChartEIS002T1
Back door warning chime order Back door warning chime length
Start self-diagnosis1.5 seconds
OK NG
1. Operating conditions diagnosis 0.5 seconds 0.2 seconds
2. Back door encoder diagnosis 0.5 seconds 0.2 seconds
3. Back door clutch diagnosis 0.5 seconds 0.2 seconds
4. Back door motor diagnosis 0.5 seconds 0.2 seconds
5. Cinch latch motor diagnosis 0.5 seconds 0.2 seconds
Restart self-diagnosis 1.5 seconds
Item NG Result Refer to
1. Operating conditions diagnosis resultOne 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 resultSensor diagnosis/short, pulse signal, pulse
signal directionBL-117
3. Back door clutch diagnosis result Back door clutch does not operateBL-124
4. Back door motor diagnosis resultBack door motor does not operate (no operat-
ing current)BL-117
5. Cinch latch motor diagnosis resultCinch latch motor does not operate (no oper-
ating current)BL-128
Symptom Suspect systems Refer to
Automatic operations are not executed from the back door fully
closed or fully open position.
(Auto closure operates normally.)Power liftgate switch system inspectionBL-118
Park switch —
Power window serial linkBL-114
Pinch strip system inspectionBL-122
Automatic operations are not carried out together with open/close
operations.
(Manual operations are normal.)Power liftgate switch system inspectionBL-118Back door close switch system inspectionBL-120
Auto back door power supply and ground cir-
cuit system inspection.BL-117
The auto closure function does not operate.
(Stops at the halfway position for auto closing operations.)Pinch strip system inspectionBL-122
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AUTOMATIC BACK DOOR SYSTEM
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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
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BL-118
AUTOMATIC BACK DOOR SYSTEM
Revision: August 20072004 QX56
Power Liftgate Switch System InspectionEIS002T3
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. 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 3.
3. POWER LIFTGATE SWITCH CIRCUIT INSPECTION
1. Disconnect power liftgate switch and back door control unit connector.
2. Check continuity between back door control unit connector (A)
B55 terminal 23 and power liftgate switch connector (B) M92 ter-
minal 1.
3. Check continuity between power liftgate switch connector (B)
M92 terminal 1 and ground.
OK or NG
OK >> GO TO 5.
NG >> Repair or replace harness.
4. POWER LIFTGATE SWITCH GROUND INSPECTION
Check continuity between power liftgate switch connector terminal 2
and ground.
OK or NG
OK >> Replace the power liftgate switch.
NG >> Repair or replace harness.
Connector terminal
(Wire color)
ConditionVoltage (V)
(Approx.)
( + ) ( - )
23 (L/W) GroundPower liftgate
switchON 0
OFF 5
LIIA0802E
1 (L/W) - 23 (L/W) : Continuity should exist.
1 (L/W) - ground : Continuity should not exist.
LIIA2254E
2 (B) - Ground : Continuity should exist.
LIIA1065E
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AUTOMATIC BACK DOOR SYSTEM
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GLASS HATCH AJAR SWITCH CHECK
1. CHECK GLASS HATCH AJAR SWITCH INPUT SIGNAL
With CONSULT-II
Check glass hatch ajar switch ("TRNK OPN MNTR") in DATA MONITOR mode with CONSULT–II. Refer to
BL-27, "
DATA MONITOR" .
When glass hatch is open:
When glass hatch is closed:
Without CONSULT-II
Check voltage between BCM connector M19 terminal 42 and ground.
OK or NG
OK >> System is OK.
NG >> GO TO 2.
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.TRNK OPN MNTR : ON
TRNK OPN MNTR : OFF
WIIA0108E
Connec-
torItemTerminals (Wire color)
ConditionVoltage (V)
(Approx.)
( + ) ( – )
M19 BCM 42 (GR) GroundOpen
↓
Closed0
↓
5
LIIA1149E
+ (GR) - 42 (GR) : Continuity should exist
+ (GR) - 17 (GR) : Continuity should exist
+ (GR) - Ground : Continuity should not exist
LIIA1547E