2004 INFINITI FX35 sensor

AT-168
DTC P1772 LOW COAST BRAKE SOLENOID VALVE
Revision: 2004 November 2004 FX35/FX45
DTC P1772 LOW COAST BRAKE SOLENOID VALVEPFP:31940
DescriptionACS007EZ
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 ValueACS007F0
On Board Diagnosis LogicACS007F1

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “LC/B SOLENOID/CIRC” with CONSULT-II or P1772 without CONSULT-II is
detected when TCM detects an improper voltage drop when it tries to operate the solenoid valve.
Possible CauseACS007F2

Harness or connectors
(Solenoid circuit is open or shorted.)

Low coast brake solenoid valve
DTC Confirmation ProcedureACS007F3
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: “M” position
Gear position: “M1-1st” or “M2-2nd” gear (LC/B ON/OFF)
5. If DTC is detected, go to AT- 1 6 9 , "
Diagnostic Procedure" .
WITH GST
Follow the procedure “With CONSULT-II”.
Item name Condition Display value
ON OFF SOLLow coast brake engaged. Refer to AT- 2 0
.ON
Low coast brake disengaged. Refer to AT- 2 0
.OFF
SAT014K

DTC P1772 LOW COAST BRAKE SOLENOID VALVE
AT-169
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Revision: 2004 November 2004 FX35/FX45
Diagnostic ProcedureACS007F4
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. Read out the value of “ON OFF SOL” while driving.
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2. CHECK SELF-DIAGNOSTIC RESULTS
Perform self-diagnosis. Refer to AT- 9 4 , "
SELF-DIAGNOSTIC RESULT MODE" .
Do the self-diagnostic results indicate
“TCM-POWER SUPPLY”?
YES >> Check the TCM power circuit. Refer to AT- 1 2 9 , "DTC P1701 TRANSMISSION CONTROL MOD-
ULE (POWER SUPPLY)" .
NO >> GO TO 3.
3. 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 2 , "Control Valve with TCM and A/T Fluid Tem-
perature Sensor 2" .
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform “DTC Confirmation Procedure”.

Refer to AT- 1 6 8 , "DTC Confirmation Procedure" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 2.
Item name Condition Display value
ON OFF
SOLLow coast brake engaged. Refer to AT- 2 0
.ON
Low coast brake disengaged. Refer to AT- 2 0
.OFF
SCIA4794E

AT-170
DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION
Revision: 2004 November 2004 FX35/FX45
DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTIONPFP:31940
DescriptionACS007F5

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 ValueACS007F6
On Board Diagnosis LogicACS007F7

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 CauseACS007F8

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

Low coast brake solenoid valve

ATF pressure switch 2
DTC Confirmation ProcedureACS007F9
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: “M” position
Gear position: “M1-1st” or “M2-2nd” 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- 1 7 1 , "
Diagnostic Pro-
cedure" .
If DTC (P1772) is detected, go to AT- 1 6 9 , "
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- 2 0
.ON
Low coast brake disengaged. Refer to AT- 2 0
.OFF
ATF PRES SW 2Low coast brake engaged. Refer to AT- 2 0
.ON
Low coast brake disengaged. Refer to AT- 2 0
.OFF
SAT014K

DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION
AT-171
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Revision: 2004 November 2004 FX35/FX45
Diagnostic ProcedureACS007FA
1. CHECK INPUT SIGNALS
With CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “SELECTION FORM MENU” in “DATA MONITOR” mode
for “A/T” with CONSULT-II.
3. Start the engine.
4. Drive vehicle in the manual mode (“M1-1st” or “M2-2nd” gear),
and confirm the ON/OFF actuation of the “ATF PRES SW 2” and
“ON OFF SOL”.
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2. CHECK SELF-DIAGNOSTIC RESULTS
Perform self-diagnosis. Refer to AT- 9 4 , "
SELF-DIAGNOSTIC RESULT MODE" .
Do the self-diagnostic results indicate
“TCM-POWER SUPPLY”?
YES >> Check the TCM power circuit. Refer to AT- 1 2 9 , "DTC P1701 TRANSMISSION CONTROL MOD-
ULE (POWER SUPPLY)" .
NO >> GO TO 3.
3. 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 2 , "Control Valve with TCM and A/T Fluid Tem-
perature Sensor 2" .
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform “DTC Confirmation Procedure”.

Refer to AT- 1 7 0 , "DTC Confirmation Procedure" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 2.
Item name Condition Display value
ON OFF
SOLLow coast brake engaged. Refer to AT- 2 0
.ON
Low coast brake disengaged. Refer to AT- 2 0
.OFF
ATF PRES
SW 2Low coast brake engaged. Refer to AT- 2 0
.ON
Low coast brake disengaged. Refer to AT- 2 0
.OFF
SCIA4794E

AT-176
DTC P1815 MANUAL MODE SWITCH
Revision: 2004 November 2004 FX35/FX45
3. DETECT MALFUNCTIONING ITEM
Check the following items.

Manual mode switch. Refer to AT- 1 7 6 , "Component Inspection" .

Terminals for damage or loose connection with harness connector.

Open circuit or short to ground or short to power in harness or connector for A/T device (manual mode
switch).

Unified meter and A/C amp. Refer to DI-28, "UNIFIED METER AND A/C AMP" .
OK or NG
OK >> GO TO 4.
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform “DTC Confirmation Procedure”.

Refer to AT- 1 7 2 , "DTC Confirmation Procedure" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 5.
5. CHECK SELF-DIAGNOSTIC RESULTS
Perform self-diagnosis. Refer to AT- 9 4 , "
SELF-DIAGNOSTIC RESULT MODE" .
Do the self-diagnostic results indicate
“TCM-POWER SUPPLY”?
YES >> Check the TCM power circuit. Refer to AT- 1 2 9 , "DTC P1701 TRANSMISSION CONTROL MOD-
ULE (POWER SUPPLY)" .
NO >> GO TO 6.
6. 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 2 , "Control Valve with TCM and A/T Fluid Tem-
perature Sensor 2" .
NG >> Repair or replace damaged parts.
Component InspectionACS007FI
MANUAL MODE SWITCH
Check continuity between terminals. Refer to AT- 1 7 3 , "Wiring Dia-
gram — AT — MMSW" .
Item Position ConnectorTerminal
(Unit side)Continuity
Manual mode
(select) switchAuto
M679 - 10
Ye s Manual 6 - 9
UP switch UP 8 - 9
DOWN switch DOWN 7 - 9
SCIA2112E

DTC P1841 ATF PRESSURE SWITCH 1
AT-179
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Revision: 2004 November 2004 FX35/FX45
Diagnostic ProcedureACS007FP
1. CHECK INPUT SIGNALS
With CONSULT-II
1. Start engine.
2. Select “ECU INPUT SIGNALS” or “MAIN SIGNALS” in “DATA
MONITOR” mode for “A/T” with CONSULT-II.
3. Drive vehicle in the “D” position (3rd
4th gear), and confirm
the ON/OFF actuation of the “ATF PRES SW 1”.
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2. CHECK SELF-DIAGNOSTIC RESULTS
Perform self-diagnosis. Refer to AT- 9 4 , "
SELF-DIAGNOSTIC RESULT MODE" .
Do the self-diagnostic results indicate
“TCM-POWER SUPPLY”?
YES >> Check the TCM power circuit. Refer to AT- 1 2 9 , "DTC P1701 TRANSMISSION CONTROL MOD-
ULE (POWER SUPPLY)" .
NO >> GO TO 3.
3. 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 2 , "Control Valve with TCM and A/T Fluid Tem-
perature Sensor 2" .
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform “DTC Confirmation Procedure”.

Refer to AT- 1 7 8 , "DTC Confirmation Procedure" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 2.
Item name Condition Display value
ATF PRES SW 1Front brake engaged. Refer to AT- 2 0
.ON
Front brake disengaged. Refer to AT- 2 0
.OFF
PCIA0067E

DTC P1843 ATF PRESSURE SWITCH 3
AT-181
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Revision: 2004 November 2004 FX35/FX45
Diagnostic ProcedureACS007FV
1. CHECK INPUT SIGNALS
With CONSULT-II
1. Start engine.
2. Select “ECU INPUT SIGNALS” or “MAIN SIGNALS” in “DATA
MONITOR” mode for “A/T” with CONSULT-II.
3. Drive vehicle in the “D” position (3rd
4th gear), and confirm
the ON/OFF actuation of the “ATF PRES SW 3”.
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2. CHECK SELF-DIAGNOSTIC RESULTS
Perform self-diagnosis. Refer to AT- 9 4 , "
SELF-DIAGNOSTIC RESULT MODE" .
Do the self-diagnostic results indicate
“TCM-POWER SUPPLY”?
YES >> Check the TCM power circuit. Refer to AT- 1 2 9 , "DTC P1701 TRANSMISSION CONTROL MOD-
ULE (POWER SUPPLY)" .
NO >> GO TO 3.
3. 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 2 , "Control Valve with TCM and A/T Fluid Tem-
perature Sensor 2" .
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform “DTC Confirmation Procedure”.

Refer to AT- 1 8 0 , "DTC Confirmation Procedure" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 2.
Item name Condition Display value
ATF PRES SW 3Input clutch engaged. Refer to AT- 2 0
.ON
Input clutch disengaged. Refer to AT- 2 0
.OFF
PCIA0067E

DTC P1845 ATF PRESSURE SWITCH 5
AT-183
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Revision: 2004 November 2004 FX35/FX45
Diagnostic ProcedureACS007G1
1. CHECK INPUT SIGNALS
With CONSULT-II
1. Start engine.
2. Select “ECU INPUT SIGNALS” or “MAIN SIGNALS” in “DATA
MONITOR” mode for “A/T” with CONSULT-II.
3. Drive vehicle in the “D” position (1st
2nd gear), and confirm
the ON/OFF actuation of the “ATF PRES SW 5”.
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2. CHECK SELF-DIAGNOSTIC RESULTS
Perform self-diagnosis. Refer to AT- 9 4 , "
SELF-DIAGNOSTIC RESULT MODE" .
Do the self-diagnostic results indicate
“TCM-POWER SUPPLY”?
YES >> Check the TCM power circuit. Refer to AT- 1 2 9 , "DTC P1701 TRANSMISSION CONTROL MOD-
ULE (POWER SUPPLY)" .
NO >> GO TO 3.
3. 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 2 , "Control Valve with TCM and A/T Fluid Tem-
perature Sensor 2" .
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform “DTC Confirmation Procedure”.

Refer to AT- 1 8 2 , "DTC Confirmation Procedure" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 2.
Item name Condition Display value
ATF PRES SW 5Direct clutch engaged. Refer to AT- 2 0
.ON
Direct clutch disengaged. Refer to AT- 2 0
.OFF
PCIA0067E