2004 INFINITI QX56 Electric

DTC P1764 DIRECT CLUTCH SOLENOID VALVE FUNCTION
AT-161
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Revision: August 20072004 QX56
Diagnostic ProcedureUCS002GZ
1. CHECK INPUT SIGNALS
With CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “SELECTION FROM MENU” in “DATA MONITOR” mode
for “A/T” with CONSULT-II.
3. Start the engine.
4. Drive vehicle in the “D” position (1st

2nd gear), and confirm
the display actuation of the “ATF PRES SW 5” and electrical cur-
rent value of “D/C SOLENOID”.
OK or NG
OK >> GO TO 6.
NG >> GO TO 2.
2. CHECK TCM
Perform TCM input/output signals inspection. Refer to AT-90, "
TCM Input/Output Signal Reference Values" .
OK or NG
OK >> GO TO 3.
NG >> GO TO 5.
3. CHECK DTC
Perform “DTC Confirmation Procedure”.

Refer to AT- 1 6 0 , "DTC Confirmation Procedure" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 4.
4. DETECT MALFUNCTIONING ITEM
Check the following items:

The A/T assembly harness connector terminals for damage or loose connection with harness connector.
OK or NG
OK >> Replace the control valve with TCM. Refer to AT - 2 4 1 , "Control Valve With TCM and A/T Fluid
Temperature Sensor 2" .
NG >> Repair or replace damaged parts.
5. DETECT MALFUNCTIONING ITEM
Check the following items:

Power supply and ground circuit for TCM.

The A/T assembly harness connector terminals for damage or loose connection with harness connector.
OK or NG
OK >> GO TO 6.
NG >> Repair or replace damaged parts.
Item name Condition Display value
(Approx)
D/C SOLENOIDDirect clutch disengaged. Refer to AT- 2 1
. 0.6 - 0.8 A
Direct clutch engaged. Refer to AT- 2 1
. 0 - 0.05 A
ATF PRES SW 5Direct clutch engaged. Refer to AT- 2 1
. ON
Direct clutch disengage. Refer to AT-2 1
.OFF
SCIA4797E

AT-166
DTC P1769 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE FUNCTION
Revision: August 20072004 QX56
DTC P1769 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE FUNCTION
PFP:31940
DescriptionUCS002H6

High and low reverse clutch solenoid valve is controlled by the TCM in response to signals sent from the
PNP switch, vehicle speed sensor and accelerator pedal position sensor (throttle position sensor). Gears
will then be shifted to the optimum position.

This is not only caused by electrical malfunction (circuits open or shorted) but also by mechanical mal-
function such as control valve sticking, improper solenoid valve operation.
CONSULT-II Reference ValueUCS002H7
On Board Diagnosis LogicUCS002H8

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “HLR/C SOL FNCTN” with CONSULT-II or P1769 without CONSULT-II is
detected under the following conditions.
–When TCM detects that actual gear ratio is irregular, and relation between gear position and condition of
ATF pressure switch 6 is irregular during depressing accelerator pedal. (Other than during shift change)
–When TCM detects that relation between gear position and condition of ATF pressure switch 6 is irregular
during releasing accelerator pedal. (Other than during shift change)
Possible CauseUCS002H9

Harness or connectors
(The solenoid and switch circuits are open or shorted.)

High and low reverse clutch solenoid valve

ATF pressure switch 6
DTC Confirmation ProcedureUCS002HA
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch “OFF”
and wait at least 10 seconds before performing the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-II
1. Start engine.
2. Accelerate vehicle to maintain the following conditions.
ACCELE POS: 1.5/8 - 2.0/8
Selector lever: “D” position
Gear position: 2nd

3rd Gear (HLR/C ON/OFF)
Driving location: Driving the vehicle uphill (increased
engine load) will help maintain the driving conditions
required for this test.
3. Perform step “2” again.
4. Turn ignition switch “OFF”, then perform step “1” to “3” again.
5. Check “SELF-DIAG RESULTS” mode for “A/T” with CONSULT-
II. If DTC (P1769) is detected, refer to AT-167, "
Diagnostic Procedure" .
If DTC (P1767) is detected, go to AT- 1 6 4 , "
Diagnostic Procedure" .
If DTC (P1846) is detected, go to AT- 1 8 5 , "
Diagnostic Procedure" .
Item name Condition Display value (Approx)
HLR/C SOL High and low reverse clutch disengaged. Refer to AT- 2 1
. 0.6 - 0.8 A
High and low reverse clutch engaged. Refer to AT- 2 1
. 0 - 0.05 A
ATF PRES SW 6High and low reverse clutch engaged. Refer to AT- 2 1
.ON
High and low reverse clutch disengaged. Refer to AT- 2 1
. OFF
BCIA0030E

DTC P1769 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE FUNCTION
AT-167
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Revision: August 20072004 QX56
WITH GST
Follow the procedure “With CONSULT-II”.
Diagnostic ProcedureUCS002HB
1. CHECK INPUT SIGNALS
With CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “SELECTION FROM MENU” in “DATA MONITOR” mode
for “A/T” with CONSULT-II.
3. Start the engine.
4. Drive vehicle in the “D” position (2nd

3rd gear), and confirm
the ON/OFF actuation of the “ATF PRES SW 6” and electrical
current value of “HLR/C SOL”.
OK or NG
OK >> GO TO 6.
NG >> GO TO 2.
2. CHECK TCM
Perform TCM input/output signals inspection. Refer to AT-90, "
TCM Input/Output Signal Reference Values" .
OK or NG
OK >> GO TO 3.
NG >> GO TO 5.
3. CHECK DTC
Perform “DTC Confirmation Procedure”.

Refer to AT- 1 6 6 , "DTC Confirmation Procedure" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 4.
4. DETECT MALFUNCTIONING ITEM
Check the following items:

The A/T assembly harness connector terminals for damage or loose connection with harness connector.
OK or NG
OK >> Replace the control valve with TCM. Refer to AT - 2 4 1 , "Control Valve With TCM and A/T Fluid
Temperature Sensor 2" .
NG >> Repair or replace damaged parts.
Item name Condition Display value
(Approx)
HLR/C SOLHigh and low reverse clutch disengaged. Refer to
AT-2 1
.0.6 - 0.8 A
High and low reverse clutch engaged. Refer to AT-
21 .0 - 0.05 A
ATF PRES
SW 6High and low reverse clutch engaged. Refer to AT-
21 .ON
High and low reverse clutch disengaged. Refer to
AT-2 1
.OFF
SCIA4798E

AT-172
DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION
Revision: August 20072004 QX56
DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTIONPFP:31940
DescriptionUCS002HI

Low coast brake solenoid valve is turned “ON” or “OFF” by the TCM in response to signals sent from the
PNP switch, vehicle speed sensor and accelerator pedal position sensor (throttle position sensor). Gears
will then be shifted to the optimum position.

This is not only caused by electrical malfunction (circuits open or shorted) but also by mechanical mal-
function such as control valve sticking, improper solenoid valve operation.
CONSULT-II Reference ValueUCS002HJ
On Board Diagnosis LogicUCS002HK

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “LC/B SOLENOID FNCT” with CONSULT-II or P1774 without CONSULT-II is
detected under the following conditions.
–When TCM detects that actual gear ratio is irregular, and relation between gear position and condition of
ATF pressure switch 2 is irregular during depressing accelerator pedal. (Other than during shift change)
–When TCM detects that relation between gear position and condition of ATF pressure switch 2 is irregular
during releasing accelerator pedal. (Other than during shift change)
Possible CauseUCS002HL

Harness or connectors
(The solenoid and switch circuits are open or shorted.)

Low coast brake solenoid valve

ATF pressure switch 2
DTC Confirmation ProcedureUCS002HM
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch “OFF”
and wait at least 10 seconds before performing the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-II
1. Start engine.
2. Accelerate vehicle to maintain the following conditions.
Selector lever: “1” or “2” position
Gear position: “1st” or “2nd” gear (LC/B ON/OFF)
3. Perform step “2” again.
4. Turn ignition switch “OFF”, then perform step “1” to “3” again.
5. Check “SELF-DIAG RESULTS” mode for “A/T” with CONSULT-
II. If DTC (P1774) is detected, refer to AT-173, "
Diagnostic Pro-
cedure" .
If DTC (P1772) is detected, go to AT-170, "
Diagnostic Proce-
dure" .
WITH GST
Follow the procedure “With CONSULT-II”.
Item name Condition Display value (ON-OFF display)
ON OFF SOLLow coast brake engaged. Refer to AT- 2 1
. ON
Low coast brake disengaged. Refer to AT- 2 1
. OFF
ATF PRES SW 2Low coast brake engaged. Refer to AT- 2 1
. ON
Low coast brake disengaged. Refer to AT- 2 1
. OFF
BCIA0030E

AT-236
A/T SHIFT LOCK SYSTEM
Revision: August 20072004 QX56
A/T SHIFT LOCK SYSTEMPFP:34950
DescriptionUCS002J 6

The electrical key interlock mechanism also operates as a shift lock:
With the ignition switch turned to ON, the selector lever cannot be shifted from “P” (parking) to any other
position unless the brake pedal is depressed.
With the key removed, the selector lever cannot be shifted from “P” to any other position.
The key cannot be removed unless the selector lever is placed in “P”.

The shift lock and key interlock mechanisms are controlled by the ON-OFF operation of the shift lock sole-
noid and by the operation of the rotator and slider located inside the key cylinder, respectively.
Shift Lock System Electrical Parts LocationUCS002J 7
LCIA0326E

PRECAUTIONS
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Revision: August 20072004 QX56
PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
EJS002BF
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SRS and SB section of this Service Man-
ual.
WA RN ING:

To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance must be per-
formed by an authorized NISSAN/INFINITI dealer.

Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS section.

Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or
harness connectors.
Precautions for Working with HFC-134a (R-134a)EJS002BG
WA RN ING:

CFC-12 (R-12) refrigerant and HFC-134a (R-134a) refrigerant are not compatible. If the refrigerants
are mixed compressor failure is likely to occur. Refer AT C - 5 , "
Contaminated Refrigerant" . To
determine the purity of HFC-134a (R-134a) in the vehicle and recovery tank, use Refrigerant
Recovery/Recycling Recharging equipment and Refrigerant Identifier.

Use only specified lubricant for the HFC-134a (R-134a) A/C system and HFC-134a (R-134a) compo-
nents. If lubricant other than that specified is used, compressor failure is likely to occur.

The specified HFC-134a (R-134a) lubricant rapidly absorbs moisture from the atmosphere. The fol-
lowing handling precautions must be observed:
–When removing refrigerant components from a vehicle, immediately cap (seal) the component to
minimize the entry of moisture from the atmosphere.
–When installing refrigerant components to a vehicle, do not remove the caps (unseal) until just
before connecting the components. Connect all refrigerant loop components as quickly as possi-
ble to minimize the entry of moisture into system.
–Only use the specified lubricant from a sealed container. Immediately reseal containers of lubri-
cant. Without proper sealing, lubricant will become moisture saturated and should not be used.
–Avoid breathing A/C refrigerant and lubricant vapor or mist. Exposure may irritate eyes, nose and
throat. Remove HFC-134a (R-134a) from the A/C system using certified service equipment meeting
requirements of SAE J2210 [HFC-134a (R-134a) recycling equipment], or J2209 [HFC-134a (R-134a)
recovery equipment]. If accidental system discharge occurs, ventilate work area before resuming
service. Additional health and safety information may be obtained from refrigerant and lubricant
manufacturers.
–Do not allow the lubricant NISSAN A/C System Lubricant Type S (DH-PS) to come in contact with
styrofoam parts. Damage may result.
Contaminated RefrigerantEJS002BH
If a refrigerant other than pure HFC-134a (R-134a) is identified in a vehicle, your options are:

Explain to the customer that environmental regulations prohibit the release of contaminated refrigerant
into the atmosphere.

Explain that recovery of the contaminated refrigerant could damage your service equipment and refriger-
ant supply.

Suggest the customer return the vehicle to the location of previous service where the contamination may
have occurred.

PRECAUTIONS
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Revision: August 20072004 QX56
SERVICE COUPLERS
Never attempt to connect HFC-134a (R-134a) service couplers to a
CFC-12 (R-12) A/C system. The HFC-134a (R-134a) couplers will
not properly connect to the CFC-12 (R-12) system. If an improper
connection is attempted, discharging and contamination may occur.
REFRIGERANT WEIGHT SCALE
Verify that no refrigerant other than HFC134a (R-134a) and specified
lubricants have been used with the scale. If the scale controls refrig-
erant flow electronically, the hose fitting must be 1/2”-16 ACME.
CHARGING CYLINDER
Using a charging cylinder is not recommended. Refrigerant may be vented into air from cylinder's top valve
when filling the cylinder with refrigerant. Also, the accuracy of the cylinder is generally less than that of an
electronic scale or of quality recycle/recharge equipment.
Wiring Diagrams and Trouble DiagnosisEJS002BO
When you read wiring diagrams, refer to the following:

GI-15, "How to Read Wiring Diagrams"

PG-4, "POWER SUPPLY ROUTING CIRCUIT"
When you perform trouble diagnosis, refer to the following:

GI-11, "How to Follow Trouble Diagnoses"

GI-27, "How to Perform Efficient Diagnosis for an Electrical Incident"
Shut-off valve rotation A/C service valve
Clockwise Open
Counterclockwise Close
RHA273D
RHA274D

TROUBLE DIAGNOSIS
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Revision: August 20072004 QX56
TROUBLE DIAGNOSISPFP:00004
CONSULT-II Function (BCM)EJS002C4
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 the
ignition switch ON.
2. Touch “START (NISSAN BASED VHCL)”.
3. Touch “BCM” on “SELECT SYSTEM” screen. If “BCM” is not
indicated, go to GI-39, "
CONSULT-II Data Link Connector (DLC)
Circuit" .
BCM diagnostic
test itemDiagnostic mode Description
Inspection by partWORK SUPPORTSupports inspections and adjustments. Commands are transmitted to the BCM
for setting the status suitable for required operation, input/output signals are
received from the BCM and received data is displayed.
DATA MONITOR Displays BCM input/output data in real time.
ACTIVE TEST Operation of electrical loads can be checked by sending drive signal to them.
SELF-DIAG RESULTS Displays BCM self-diagnosis results.
CAN DIAG SUPPORT MNTR The result of transmit/receive diagnosis of CAN communication can be read.
ECU PART NUMBER BCM part number can be read.
CONFIGURATION Performs BCM configuration read/write functions.
BBIA0369E
BCIA0029E
BCIA0030E