2005 INFINITI QX4 ESP

AT-146
DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTION
Revision: October 20052005 QX56
DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTIONPFP:31940
DescriptionECS00CHZ

Front brake solenoid valve is controlled by the TCM in response to signals sent from the PNP switch, vehi-
cle 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 ValueECS00CI0
On Board Diagnosis LogicECS00CI1

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “P1759 FR/B SOLENOID FNCT” with CONSULT-II is detected under the follow-
ing conditions.
–When TCM detects that actual gear ratio is irregular, and relation between gear position and condition of
ATF pressure switch 1 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 1 is irregular
during releasing accelerator pedal. (Other than during shift change)
Possible CauseECS00CI2

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

Front brake solenoid valve

ATF pressure switch 1
DTC Confirmation ProcedureECS00CI3
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: 3rd

4th Gear (FR/B 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 (P1759) is detected, refer to AT-147, "
Diagnostic Procedure" .
If DTC (P1757) is detected, go to AT- 1 4 5 , "
Diagnostic Procedure" .
If DTC (P1841) is detected, go to AT- 1 6 1 , "
Diagnostic Procedure" .
Item name Condition Display value (Approx.)
FR/B SOLENOIDFront brake engaged. Refer to AT- 1 9
.0.6 - 0.8 A
Front brake disengaged. Refer to AT- 1 9
. 0 - 0.05 A
ATF PRES SW 1Front brake engaged. Refer to AT- 1 9
.ON
Front brake disengaged. Refer to AT- 1 9
.OFF
BCIA0030E

AT-148
DTC P1762 DIRECT CLUTCH SOLENOID VALVE
Revision: October 20052005 QX56
DTC P1762 DIRECT CLUTCH SOLENOID VALVEPFP:31940
DescriptionECS00CI5
Direct 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.
CONSULT-II Reference ValueECS00CI6
On Board Diagnosis LogicECS00CI7

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “P1762 D/C SOLENOID/CIRC” with CONSULT-II is detected under the following
conditions.
–When TCM detects an improper voltage drop when it tries to operate the solenoid valve.
–When TCM detects as irregular by comparing target value with monitor value.
Possible CauseECS00CI8

Harness or connectors
(The solenoid circuit is open or shorted.)

Direct clutch solenoid valve
DTC Confirmation ProcedureECS00CI9
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. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “A/T” with CONSULT-II.
3. Start engine.
4. Drive vehicle and maintain the following conditions for at least 5
consecutive seconds.
ACCELE POS: 1.5/8 - 2.0/8
Selector lever: “D” position
Gear position: 1st

2nd Gear (D/C ON/OFF)
Driving location: Driving the vehicle uphill (increased
engine load) will help maintain the driving conditions
required for this test.
5. If DTC is detected, go to AT-149, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “With CONSULT-II”.
Item name Condition Display value (Approx.)
D/C SOLENOIDDirect clutch disengaged. Refer to AT-1 9
. 0.6 - 0.8 A
Direct clutch engaged. Refer to AT-1 9
. 0 - 0.05 A
BCIA0030E

AT-150
DTC P1764 DIRECT CLUTCH SOLENOID VALVE FUNCTION
Revision: October 20052005 QX56
DTC P1764 DIRECT CLUTCH SOLENOID VALVE FUNCTIONPFP:31940
DescriptionECS00CIB

Direct 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 ValueECS00CIC
On Board Diagnosis LogicECS00CID

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “P1764 D/C SOLENOID FNCTN” with CONSULT-II is detected under the follow-
ing conditions.
–When TCM detects that actual gear ratio is irregular, and relation between gear position and condition of
ATF pressure switch 5 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 5 is irregular
during releasing accelerator pedal. (Other than during shift change)
Possible CauseECS00CIE

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

Direct clutch solenoid valve

ATF pressure switch 5
DTC Confirmation ProcedureECS00CIF
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: 1st

2nd Gear (D/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 (P1764) is detected, refer to AT-151, "
Diagnostic Procedure" .
If DTC (P1762) is detected, go to AT- 1 4 9 , "
Diagnostic Procedure" .
If DTC (P1845) is detected, go to AT- 1 6 5 , "
Diagnostic Procedure" .
WITH GST
Follow the procedure “With CONSULT-II”.
Item name Condition Display value (Approx.)
D/C SOLENOIDDirect clutch disengaged. Refer to AT-1 9
. 0.6 - 0.8 A
Direct clutch engaged. Refer to AT-1 9
. 0 - 0.05 A
ATF PRES SW 5Direct clutch engaged. Refer to AT-1 9
.ON
Direct clutch disengaged. Refer to AT-1 9
.OFF
BCIA0030E

AT-152
DTC P1767 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE
Revision: October 20052005 QX56
DTC P1767 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVEPFP:31940
DescriptionECS00CIH
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.
CONSULT-II Reference ValueECS00CII
On Board Diagnosis LogicECS00CIJ

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “P1767 HLR/C SOL/CIRC” with CONSULT-II or is detected under the following
conditions.
–When TCM detects an improper voltage drop when it tries to operate the solenoid valve.
–When TCM detects as irregular by comparing target value with monitor value.
Possible CauseECS00CIK

Harness or connectors
(The solenoid circuit is open or shorted.)

High and low reverse clutch solenoid valve
DTC Confirmation ProcedureECS00CIL
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. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “A/T” with CONSULT-II.
3. Start engine.
4. Drive vehicle and maintain the following conditions for at least 5
consecutive seconds.
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.
5. If DTC is detected, go to AT-153, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “With CONSULT-II”.
Item name Condition Display value (Approx.)
HLR/C SOLHigh and low reverse clutch disengaged. Refer to AT- 1 9
.0.6 - 0.8 A
High and low reverse clutch engaged. Refer to AT- 1 9
. 0 - 0.05 A
BCIA0030E

AT-154
DTC P1769 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE FUNCTION
Revision: October 20052005 QX56
DTC P1769 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE FUNCTION
PFP:31940
DescriptionECS00CIN

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 ValueECS0 0CIO
On Board Diagnosis LogicECS00CIP

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “P1769 HLR/C SOL FNCTN” with 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 CauseECS0 0CIQ

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 ProcedureECS00CIR
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-155, "
Diagnostic Procedure" .
If DTC (P1767) is detected, go to AT- 1 5 3 , "
Diagnostic Procedure" .
If DTC (P1846) is detected, go to AT- 1 6 7 , "
Diagnostic Procedure" .
Item name Condition Display value (Approx.)
HLR/C SOL High and low reverse clutch disengaged. Refer to AT- 1 9
.0.6 - 0.8 A
High and low reverse clutch engaged. Refer to AT- 1 9
. 0 - 0.05 A
ATF PRES SW 6High and low reverse clutch engaged. Refer to AT- 1 9
.ON
High and low reverse clutch disengaged. Refer to AT- 1 9
.OFF
BCIA0030E

AT-156
DTC P1772 LOW COAST BRAKE SOLENOID VALVE
Revision: October 20052005 QX56
DTC P1772 LOW COAST BRAKE SOLENOID VALVEPFP:31940
DescriptionECS00CIT
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.
CONSULT-II Reference ValueECS00CIU
On Board Diagnosis LogicECS00CIV

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “P1772 LC/B SOLENOID/CIRC” with CONSULT-II is detected when TCM detects
an improper voltage drop when it tries to operate the solenoid valve.
Possible CauseECS00CIW

Harness or connectors
(The solenoid circuit is open or shorted.)

Low coast brake solenoid valve
DTC Confirmation ProcedureECS00CIX
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. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “ENGINE” with CONSULT-II.
3. Start engine.
4. Drive vehicle and maintain the following conditions for at least 5
consecutive seconds.
Selector lever: “1” or “2”
Gear position: “1st” or “2nd” gear (LC/B ON/OFF)
5. If DTC is detected, go to AT-157, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “With CONSULT-II”.
Item name Condition Display value
ON OFF SOLLow coast brake engaged. Refer to AT- 1 9
.ON
Low coast brake disengaged. Refer to AT- 1 9
.OFF
BCIA0030E

AT-158
DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION
Revision: October 20052005 QX56
DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTIONPFP:31940
DescriptionECS00CIZ

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 ValueECS0 0CJ 0
On Board Diagnosis LogicECS0 0CJ 1

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “P1774 LC/B SOLENOID FNCT” with 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 CauseECS0 0CJ 2

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

Low coast brake solenoid valve

ATF pressure switch 2
DTC Confirmation ProcedureECS0 0CJ 3
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-159, "
Diagnostic Pro-
cedure" .
If DTC (P1772) is detected, go to AT-157, "
Diagnostic Proce-
dure" .
WITH GST
Follow the procedure “With CONSULT-II”.
Item name Condition Display value
ON OFF SOLLow coast brake engaged. Refer to AT- 1 9
.ON
Low coast brake disengaged. Refer to AT- 1 9
.OFF
ATF PRES SW 2Low coast brake engaged. Refer to AT- 1 9
.ON
Low coast brake disengaged. Refer to AT- 1 9
.OFF
BCIA0030E

AT-222
A/T SHIFT LOCK SYSTEM
Revision: October 20052005 QX56
A/T SHIFT LOCK SYSTEMPFP:34950
DescriptionECS00CKO

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 LocationECS00CKP
LCIA0326E