2004 INFINITI QX56 Engine Control System

IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
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CONSULT-II Function (IPDM E/R)EKS007NQ
CONSULT-II can display each diagnostic item using the diagnostic test modes shown following.
CONSULT-II BASIC OPERATION
CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on control unit which carries out CAN communication.
1. With the ignition switch OFF, connect CONSULT-II and CON-
SULT-II CONVERTER to the data link connector, then turn igni-
tion switch ON.
2. Touch “START (NISSAN BASED VHCL)”.
3. Touch “IPDM E/R” on “SELECT SYSTEM” screen.

If “IPDM E/R” is not displayed, print "SELECT SYSTEM"
screen, then refer to GI-39, "
CONSULT-II Data Link Connec-
tor (DLC) Circuit" .
IPDM E/R diagnostic mode Description
SELF-DIAG RESULTS Displays IPDM E/R self-diagnosis results.
DATA MONITOR Displays IPDM E/R input/output data in real time.
CAN DIAG SUPPORT MNTR The result of transmit/receive diagnosis of CAN communication can be read.
ACTIVE TEST Operation of electrical loads can be checked by sending drive signal to them.
BBIA0369E
BCIA0029E
BCIA0030E

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IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
Revision: August 20072004 QX56
Concept of Auto Active Test

IPDM E/R actuates auto active test mode when it receives door switch signal from BCM via CAN commu-
nication line. Therefore, when auto active test mode is activated successfully, CAN communication
between IPDM E/R and BCM is normal.

If any of the systems controlled by IPDM E/R cannot be operated, possible cause can be easily diagnosed
using auto active test.
Diagnosis chart in auto active test mode
Symptom Inspection contents Possible cause
Rear window defogger
does not operate.Perform auto active
test. Does rear win-
dow defogger oper-
ate?YES

BCM signal input circuit
NO

Rear window defogger relay

Open circuit of rear window defogger

IPDM E/R malfunction

Harness or connector malfunction between IPDM E/R and rear window
defogger
Any of front wipers, tail
and parking lamps, front
fog lamps, and head-
lamps (Hi, Lo) do not
operate.Perform auto active
test. Does system in
question operate?YES

BCM signal input system
NO

Lamp/wiper motor malfunction

Lamp/wiper motor ground circuit malfunction

Harness/connector malfunction between IPDM E/R and system in
question

IPDM E/R (integrated relay) malfunction
A/C compressor does
not operate.Perform auto active
test. Does magnet
clutch operate?YES

BCM signal input circuit

CAN communication signal between BCM and ECM

CAN communication signal between ECM and IPDM E/R
NO

Magnet clutch malfunction

Harness/connector malfunction between IPDM E/R and magnet clutch

IPDM E/R (integrated relay) malfunction
Cooling fan does not
operate.Perform auto active
test. Does cooling fan
operate?YES

ECM signal input circuit

CAN communication signal between ECM and IPDM E/R
NO

Cooling fan motor malfunction

Harness/connector malfunction between IPDM E/R and cooling fan
motor

IPDM E/R (integrated relay) malfunction

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IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
Revision: August 20072004 QX56
Inspection with CONSULT-II (Self-Diagnosis)EKS007NV
CAUTION:
If a CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on which control unit(s) carry out CAN communication.
1. SELF-DIAGNOSIS RESULT CHECK
1. Connect CONSULT-II and select "IPDM E/R" on the Diagnosis System Selection screen.
2. Select "SELF-DIAG RESULTS" on the diagnosis mode selection screen.
3. Check display content in self-diagnosis results.
NOTE:
The Details for Display for the Period are as follows:

CRNT: Error currently detected by IPDM E/R.

PAST: Error detected in the past and stored in IPDM E/R memory.
Contents displayed
NO DTC DETECTED. FURTHER TESTING MAY BE REQUIRED.>>Inspection End.
CAN COMM CIRC>>Print out the self-diagnosis result and refer to LAN-5, "
CAN COMMUNICATION" .
CONSULT-II DisplayCONSULT-II
display codeTIME
Details of diagnosis result
CRNT PAST
NO DTC IS DETECTED.
FURTHER TESTING MAY BE REQUIRED.— — — No malfunction
CAN COMM CIRC U1000 X XAny of items listed below have errors:

TRANSMIT DIAG

ECM

BCM/SEC

HARNESS
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Wiring Diagram Codes (Cell Codes)EKS007NZ
Use the chart below to find out what each wiring diagram code stands for.
Refer to the wiring diagram code in the alphabetical index to find the location (page number) of each wiring
diagram.
Code Section Wiring Diagram Name
A/C,A ATC Auto Air Conditioner
A/SUSP RSU Rear Air Suspension
AF1B1 EC Air Fuel Ratio Sensor 1 (Bank 1)
AF1B2 EC Air Fuel Ratio Sensor 1 (Bank 2)
AF1HB1 EC Air Fuel Ratio Sensor 1 (Bank 1)
AF1HB2 EC Air Fuel Ratio Sensor 1 (Bank 2)
APPS1 EC Accelerator Pedal Position Sensor
APPS2 EC Accelerator Pedal Position Sensor
APPS3 EC Accelerator Pedal Position Sensor
ASC/BS EC ASCD Brake Switch
ASC/SW EC ASCD Steering Switch
ASCBOF EC ASCD Brake Switch
ASCIND EC ASCD Indicator
A/T AT A/T Assembly
AT/IND DI A/T Indicator Lamp
AUDIO AV Audio
AUTO/DP SE Automatic Drive Positioner
AUTO/L LT Auto Light Control
B/CLOS BL Back Door Auto Closure System
BACK/L LT Back-up Lamp
BRK/SW EC Brake Switch
CAN EC CAN Communication Line
CAN LAN CAN System
CHARGE SC Charging System
CHIME DI Warning Chime
CLOCK DI Clock
COMBSW LT Combination Switch
COMM AV Audio Visual Communication System
COMPAS DI Compass and Thermometer
COOL/F EC Cooling Fan Control
D/LOCK BL Power Door Lock
DEF GW Rear Window Defogger
DTRL LT Headlamp - With Daytime Light System
DVD AV DVD Entertainment System
ECM/PW EC ECM Power Supply for Back-Up
ECTS EC Engine Coolant Temperature Sensor
ETC1 EC Electric Throttle Control Function
ETC2 EC Throttle Control Motor Relay
ETC3 EC Throttle Control Motor
F/FOG LT Front Fog Lamp
F/PUMP EC Fuel Pump
FTTS EC Fuel Tank Temperature Sensor
FUELB1 EC Fuel Injection System Bank 1
FUELB2 EC Fuel Injection System Bank 2
H/AIM LT Headlamp Aiming Control
H/LAMP LT Headlamp
HORN WW Horn

RSU-12
TROUBLE DIAGNOSIS
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Basic InspectionEES00116
AIR HOSES
1. Check for pinched or damaged air hoses between the suspension air reservoir and each load leveling rear
air suspension shock absorber. Reposition, repair or replace hoses as necessary.
2. Check the air hose connections at the suspension air reservoir and at the shock absorbers for leaks. If
connections are leaking, repair or replace hoses as necessary.
POWER SYSTEM TERMINAL LOOSENESS AND BATTERY INSPECTION
Make sure the battery positive cable, negative cable and ground connection are not loose. In addition, make
sure the battery is sufficiently charged.
CK SUSP INDICATOR LAMP INSPECTION
1. Make sure the CK SUSP indicator lamp turns on for approximately 2 seconds when the ignition switch is
turned ON. If it does not, check the combination meter. Refer to DI-5, "
COMBINATION METERS" .
2. Make sure the lamp turns off approximately 2 seconds after the ignition switch is turned ON. If the lamp
does not turn off, conduct self-diagnosis of the suspension control unit.
3. After conducting the self-diagnosis, be sure to erase the error memory. Refer to RSU-13, "
CONSULT-II
Function (AIR LEVELIZER)" .
CK SUSP Indicator Lamp TimingEES00117
X: ON
—: OFF
Control Unit Input/Output Signal StandardEES00118
( ): Wire colorConditionCK SUSP
indicator lampRemarks
Ignition switch OFF – –
Ignition switch ON X Turns off after approximately 2 seconds.
Te r m i n a l
Item ConditionVoltage (V)
(Approx.)
+–
1 (V)
GroundCompressor relay output
Ignition switch ON or STARTBattery voltage
3 (W) Height sensor signal input 0.2V - 4.8V
5 (R) Reference voltage 5V
6 (G/R) Ignition power
Battery voltage
7 (W/L) Battery power —
8 (G/W) Diagnostic K-line — —
9 (SB) Exhaust valve output Ignition switch ON or START Battery voltage
10 (BR) Warning lamp output — —
14 (L) Height sensor ground — —
15 (BR/W) Alternator L signal input Engine running —
16 (B) Suspension control unit ground — 0V

RSU-14
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
6. Select the required operation from the "SELECT DIAG MODE"
screen.
For further information, see the CONSULT-II Operation Manual.
WORK SUPPORT
Operation Procedure
1. Touch “AIR LEVELIZER” on “SELECT SYSTEM” screen.
2. Touch “WORK SUPPORT” on “SELECT DIAG MODE” screen.
3. Touch item on “SELECT WORK ITEM” screen.
4. Touch “START”.
5. The setting will be changed and “ADJUSTMENT COMPLETE” will be displayed.
6. Touch “END”.
Display Item List
SELF-DIAGNOSIS
Description
If an error is detected in the system, perform self-diagnosis as follows:
Operation Procedure
1. Turn ignition switch OFF.
2. Connect CONSULT-II and CONSULT-II CONVERTER to the data link connector.
CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on control unit which carries out CAN communication.
3. Turn ignition switch ON.
4. After stopping the vehicle, with the engine running, touch “START (NISSAN BASED VHCL)”, "AIR LEVEL-
IZER", “SELF-DIAG RESULTS” in order on the CONSULT-II screen.
CAUTION:
If “START (NISSAN BASED VHCL)” is touched immediately after starting the engine or turning on
the ignition switch, "AIR LEVELIZER" might not be displayed in the "SELECT SYSTEM" screen. In
this case, repeat the operation from step 1.
5. The self-diagnostic results are displayed. (If necessary, the self-diagnostic results can be printed out by
touching “COPY”.)

When “NO DTC IS DETECTED” is displayed, check the CK SUSP indicator lamp.
6. Conduct the appropriate inspection from the display item list, and repair or replace the malfunctioning
component.
7. Start and run the vehicle for approximately 1 minute.
8. Turn ignition switch OFF to prepare for erasing the memory.
9. Start the engine and touch “START (NISSAN BASED VHCL)”, "AIR LEVELIZER", “SELF-DIAG
RESULTS”, “ERASE” in order on the CONSULT-II screen to erase the error memory.
If "AIR LEVELIZER" is not indicated, go to GI-39, "
CONSULT-II Data Link Connector (DLC) Circuit" .
BCIA0031E
Item Description
STANDARD HEIGHT LEVEL This mode allows the vehicle height to be set to vehicle height specification within tolerance.
ADJUST HEIGHT INI The initialization value and flag can be set in the suspension control unit in this mode.
CLEAR HEIGHT INI This mode clears the initialization flag and value in the suspension control unit.

TROUBLE DIAGNOSIS
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Revision: August 20072004 QX56
CAUTION:
If the error memory is not erased, re-conduct the operation from step 7.
10. For the final inspection, start and run the vehicle for approximately 1 minute and confirm that the CK
SUSP indicator lamp is off.
Display Item List
DATA MONITOR
Operation Procedure
1. After turning OFF the ignition switch, connect CONSULT-II and the CONSULT-II CONVERTER to the data
link connector.
CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on control unit which carries out CAN communication.
2. Touch “START (NISSAN BASED VHCL)”, "AIR LEVELIZER", “DATA MONITOR” in order on the CON-
SULT-II screen.
If "AIR LEVELIZER" is not indicated, go to GI-39, "
CONSULT-II Data Link Connector (DLC) Circuit" .
CAUTION:
When “START (NISSAN BASED VHCL)” is touched immediately after starting the engine or turning
on the ignition switch, "AIR LEVELIZER" might not be displayed in the "SELECT SYSTEM" screen.
In this case, repeat the operation from step 2.
3. Return to the "SELECT MONITOR ITEM" screen, and touch "ALL SIGNALS" or "SELECTION FROM
MENU". Refer to the following information.
4. When “START” is touched, the data monitor screen is displayed.
Self-diagnostic item Malfunction detecting condition Check system
Vehicle height sensor
[C1801]Vehicle height sensor voltage is less than 0.2V or greater than
4.8V for more than 60 seconds.Refer to RSU-17, "
Height
Sensor System Inspection" .
Compressor relay
[C1802]1. Driving transistor for compressor relay is off and monitor volt-
age continues high level for more than 10 seconds.
2. Driving transistor for compressor relay is on and monitor volt-
age continues low level for more than 5 seconds.Refer to RSU-20, "
Compres-
sor Motor, Compressor
Motor Relay and Circuit
Inspection" .
Exhaust solenoid
[C1803]1. Driving transistor for exhaust solenoid is off and monitor volt-
age continues high level for more than 10 seconds.
2. Driving transistor for exhaust solenoid is on and monitor volt-
age continues low level for more than 5 seconds.Refer to RSU-19, "
Exhaust
Valve Solenoid System
Inspection" .
Vehicle height adjusting trouble
(compressor)
[C1804]Continuous compressor relay ON time is more than 120 sec-
onds.Refer to RSU-20, "
Compres-
sor Motor, Compressor
Motor Relay and Circuit
Inspection" .
Vehicle height adjusting trouble
(exhaust solenoid)
[C1805]Continuous exhaust solenoid ON time is more than 120 seconds.Refer to RSU-19, "
Exhaust
Valve Solenoid System
Inspection" .
Vehicle height sensor locking trou-
ble
[C1806]Output sensor voltage variation ±0.02V is more than 100 hour
when vehicle height range is normal.Refer to RSU-17, "
Height
Sensor System Inspection" .
Sensor 5V trouble
[C1807]Sensor reference voltage is less than 0.8V or more than 6V for
20 seconds.Refer to RSU-17, "
Height
Sensor System Inspection" .
Integral time trouble by supplying
air
[C1808]Integral discontinuous time on the compressor is more than 180
seconds.Refer to RSU-20, "
Compres-
sor Motor, Compressor
Motor Relay and Circuit
Inspection" .

RSU-16
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
Display Item List
X: Applicable
–: Not applicable
ACTIVE TEST
CAUTION:

Do not perform active test while driving.
Operation Procedure
1. Connect the CONSULT-II and CONSULT-II CONVERTER to the data link connector and start the engine.
CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on control unit which carries out CAN communication.
2. Touch “START (NISSAN BASED VHCL) ” on the display screen.
3. Touch "AIR LEVELIZER".
If "AIR LEVELIZER" is not indicated, go to GI-39, "
CONSULT-II Data Link Connector (DLC) Circuit" .
4. Touch “ACTIVE TEST”.
5. The "SELECT TEST ITEM" screen is displayed.
6. Touch necessary test item.
7. With the "MAIN SIGNALS" display highlighted, touch “START”.
8. The active test screen will be displayed.
Display Item List
CAUTION:
The "COMPRESSOR" active test will remain ON until it is turned off using CONSULT-II. Allowing the
compressor to run for an extended period of time may cause damage to air suspension system com-
ponents due to excessive pressure in the air suspension system.
NOTE:

“TEST IS STOPPED” is displayed approximately 10 seconds after operation starts for all active test items
except "COMPRESSOR".

After “TEST IS STOPPED” is displayed, to perform test again, repeat Step 6.
Te s t I t e mData monitor item selection
ALL
SIGNALSSELECTION
FROM MENU
HEIGT SENXX
HEIGT CALCXX
SEN FIX TIMEXX
HEIGT INI VALXX
COMPRESSOR X X
EXH SOLENOID X X
ACG LXX
Test Item Description
COMPRESSOROFF/ON
EXHAUST SOLENOIDOFF/ON
WARNING LAMPOFF/ON