AT-154
DTC P1772 LOW COAST BRAKE SOLENOID VALVE
Revision: 2006 November2007 350Z
Diagnostic ProcedureNCS0006T
1. CHECK INPUT SIGNAL
With CONSULT-III
1. Turn ignition switch ON.
2. Select “SELECTION FROM MENU” in “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.
3. Start 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 TCM POWER SUPPLY AND GROUND CIRCUIT
Check TCM power supply and ground circuit. Refer to AT- 1 6 2 , "
MAIN POWER SUPPLY AND GROUND CIR-
CUIT" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. DETECT MALFUNCTIONING ITEM
Check A/T assembly harness connector pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> Replace control valve with TCM. Refer to AT- 2 1 5 , "Control Valve with TCM and A/T Fluid Temper-
ature Sensor 2" .
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform AT- 1 5 3 , "
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- 1 9
.ON
Low coast brake disengaged. Refer to AT- 1 9
.OFF
DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION
AT-155
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Revision: 2006 November2007 350Z
DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTIONPFP:31940
DescriptionNCS0006U
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-III Reference ValueNCS0006V
On Board Diagnosis LogicNCS0006W
This is an OBD-II self-diagnostic item.
Diagnostic trouble code “P1774 LC/B SOLENOID FNCT” with CONSULT-III or 7th judgment flicker with-
out CONSULT-III 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 CauseNCS0006X
Harness or connectors
(The solenoid and switch circuits are open or shorted.)
Low coast brake solenoid valve
ATF pressure switch 2
DTC Confirmation ProcedureNCS0006Y
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-III
1. Start engine.
2. Accelerate vehicle to maintain the following conditions.
MANU MODE SW: ON
GEAR: “1” or “2” (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 “TRANSMISSION” with CONSULT-III.
If DTC (P1774) is detected, refer to AT- 1 5 6 , "
Diagnostic Procedure" .
If DTC (P1772) is detected, go to AT- 1 5 4 , "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III”.
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
AT-156
DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION
Revision: 2006 November2007 350Z
Diagnostic ProcedureNCS0006Z
1. CHECK INPUT SIGNALS
With CONSULT-III
1. Start engine.
2. Select “SELECTION FROM MENU” in “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.
3. Drive vehicle in the manual mode (“1” or “2” 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 TCM POWER SUPPLY AND GROUND CIRCUIT
Check TCM power supply and ground circuit. Refer to AT- 1 6 2 , "
MAIN POWER SUPPLY AND GROUND CIR-
CUIT" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. DETECT MALFUNCTIONING ITEM
Check A/T assembly harness connector pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> Replace control valve with TCM. Refer to AT- 2 1 5 , "Control Valve with TCM and A/T Fluid Temper-
ature Sensor 2" .
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform AT- 1 5 5 , "
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- 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
DTC P1815 MANUAL MODE SWITCH
AT-157
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Revision: 2006 November2007 350Z
DTC P1815 MANUAL MODE SWITCHPFP:34901
DescriptionNCS00070
Manual mode switch is installed in A/T device. It sends manual mode switch, shift up and shift down switch
signals to TCM.
TCM sends the switch signals to unified meter and A/C amp. By CAN communication line. Then manual mode
switch position is indicated on the A/T position indicator. For inspection, refer to AT- 1 6 8 , "
A/T INDICATOR
CIRCUIT" .
CONSULT-III Reference Value in Data Monitor ModeNCS00071
On Board Diagnosis LogicNCS00072
This is not an OBD-II self-diagnostic item.
Diagnostic trouble code “P1815 MANU MODE SW/CIRC” with CONSULT-III is detected when TCM moni-
tors Manual mode, Non manual mode, Up or Down switch signal, and detects as irregular when impossi-
ble input pattern occurs 1 second or more.
Possible CauseNCS00073
Harness or connectors
(These switches circuit is open or shorted.)
Manual mode select switch (Into control device)
Manual mode position select switch (Into control device)
DTC Confirmation ProcedureNCS00074
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-III
1. Turn ignition switch ON.
2. Select “ECU INPUT SIGNALS” in “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.
3. Start engine.
4. Move selector lever to “M” position.
5. Drive vehicle and maintain the following conditions for at least 2 consecutive seconds.
MANU MODE SW: ON
6. If DTC is detected, go to AT- 1 6 0 , "
Diagnostic Procedure" .
Item name Condition Display Value
MANU MODE SWManual shift gate position (neutral) ON
Other than the above OFF
NON M-MODE SWManual shift gate position OFF
Other than the above ON
UP SW LEVERSelector lever: + side ON
Other than the above OFF
DOWN SW LEVERSelector lever: - side ON
Other than the above OFF
AT-160
DTC P1815 MANUAL MODE SWITCH
Revision: 2006 November2007 350Z
TCM terminals and data are reference value. Measured between each terminal and ground.
Diagnostic ProcedureNCS00076
1. CHECK CAN COMMUNICATION LINE
Perform self-diagnosis. Refer to AT- 8 6 , "
SELF-DIAGNOSTIC RESULT MODE" .
Is a malfunction in the CAN communication indicated in the results?
YES >> Check CAN communication line. Refer to AT- 9 4 , "DTC U1000 CAN COMMUNICATION LINE" .
NO >> GO TO 2.
2. CHECK MANUAL MODE SWITCH CIRCUIT
With CONSULT-III
1. Turn ignition switch ON.
2. Select “ECU INPUT SIGNALS” in “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.
3. Read out ON/OFF switching action of “MANU MODE SW”, “NON M-MODE SW”, “UP SW LEVER”,
“DOWN SW LEVER”.
Without CONSULT-III
Drive vehicle in the manual mode, and confirm that the actual gear position and the meter's indication of the
position mutually coincide when the selector lever is shifted to the “+ (up)” or “- (down)” side (1st ⇔ 5th gear).
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3. DETECT MALFUNCTIONING ITEM
Check the following.
Manual mode switch. Refer to AT- 1 6 1 , "Component Inspection" .
Pin 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-44, "UNIFIED METER AND A/C AMP" .
OK or NG
OK >> GO TO 4.
NG >> Repair or replace damaged parts.
TerminalWire
colorItem Condition Data (Approx.)
3 L CAN-H — —
8 P CAN-L — —
Item name Condition Display Value
MANU MODE SWManual shift gate position (neutral) ON
Other than the above OFF
NON M-MODE SWManual shift gate position OFF
Other than the above ON
UP SW LEVERselector lever: +side ON
Other than the above OFF
DOWN SW LEVERselector lever: -side ON
Other than the above OFF
AT-164
MAIN POWER SUPPLY AND GROUND CIRCUIT
Revision: 2006 November2007 350Z
3. DETECT MALFUNCTIONING ITEM
Check the following.
Harness for short or open between battery and A/T assembly harness connector terminals 1, 2
Harness for short or open between ignition switch and A/T assembly harness connector terminal 6
10 A fuse (No. 32, located in the fuse and fusible link block) and 10 A fuse (No. 83, located in the IPDM E/
R)
Ignition switch, Refer to PG-4, "POWER SUPPLY ROUTING CIRCUIT" .
OK or NG
OK >> GO TO 4.
NG >> Repair or replace damaged parts.
4. CHECK TCM GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect A/T assembly harness connector.
3. Check continuity between A/T assembly harness connector ter-
minals and ground.
If OK, check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
5. DETECT MALFUNCTIONING ITEM
Check A/T assembly harness connector pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> GO TO 6.
NG >> Repair or replace damaged parts.
6. PERFORM SELF-DIAGNOSIS
Perform self-diagnosis. Refer to AT- 8 6 , "
SELF-DIAGNOSTIC RESULT MODE" .
OK or NG
OK >>INSPECTION END
NG-1 >> Self-diagnosis does not activate: GO TO 7.
NG-2 >> DTC is displayed: Check the malfunctioning system. Refer to AT- 8 6 , "
SELF-DIAGNOSTIC
RESULT MODE" .
Item Connector Terminal Continuity
TCM F6 5, 10 – Ground Yes
SCIA2106E
AT-166
CLOSED THROTTLE POSITION AND WIDE OPEN THROTTLE POSITION CIR-
CUIT
Revision: 2006 November2007 350Z
CLOSED THROTTLE POSITION AND WIDE OPEN THROTTLE POSITION CIR-
CUIT
PFP:18002
CONSULT-III Reference ValueNCS0007Y
Diagnostic ProcedureNCS0007Z
1. CHECK CAN COMMUNICATION LINE
Perform self-diagnosis. Refer to AT- 8 6 , "
SELF-DIAGNOSTIC RESULT MODE" , AT- 9 2 , "TCM SELF-DIAG-
NOSTIC PROCEDURE (NO TOOLS)" .
Is a malfunction in the CAN communication indicated in the results?
YES >> Check CAN communication line. Refer to AT- 9 4 , "DTC U1000 CAN COMMUNICATION LINE" .
NO >> GO TO 2.
2. CHECK THROTTLE POSITION SIGNAL CIRCUIT
With CONSULT-III
1. Turn ignition switch ON.
2. Select “ECU INPUT SIGNALS” in “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.
3. Depress accelerator pedal and read out the value of “CLSD THL POS” and “W/O THL POS”.
OK or NG
OK >>INSPECTION END
NG >> Check the following. If NG, repair or replace damaged parts.
Perform self-diagnosis for “ENGINE” with CONSULT-III. Refer to EC-116, "CONSULT-III Func-
tion (ENGINE)" .
Open circuit or short to ground or short to power in harness or connectors.
Pin terminals for damage or loose connection with harness connector.
Item name Condition Display value
CLSD THL POSReleased accelerator pedal. ON
Fully depressed accelerator pedal. OFF
W/O THL POSFully depressed accelerator pedal. ON
Released accelerator pedal. OFF
Accelerator Pedal OperationMonitor Item
CLSD THL POS W/O THL POS
Released ON OFF
Fully depressed OFF ON
BRAKE SIGNAL CIRCUIT
AT-167
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Revision: 2006 November2007 350Z
BRAKE SIGNAL CIRCUITPFP:25320
CONSULT-III Reference ValueNCS00080
Diagnostic ProcedureNCS00081
1. CHECK CAN COMMUNICATION LINE
Perform self-diagnosis. Refer to AT- 8 6 , "
SELF-DIAGNOSTIC RESULT MODE" , AT- 9 2 , "TCM SELF-DIAG-
NOSTIC PROCEDURE (NO TOOLS)" .
Is a malfunction in the CAN communication indicated in the results?
YES >> Check CAN communication line. Refer to AT- 9 4 , "DTC U1000 CAN COMMUNICATION LINE" .
NO >> GO TO 2.
2. CHECK STOP LAMP SWITCH CIRCUIT
With CONSULT-III
1. Turn ignition switch ON.
2. Select “ECU INPUT SIGNALS” in “DATA MONITOR” mode for “TRANSMISSION” with CONSULT-III.
3. Read out ON/OFF switching action of the “BRAKE SW”.
OK or NG
OK >>INSPECTION END
NG >> GO TO 3.
3. CHECK STOP LAMP SWITCH
Check continuity between stop lamp switch harness connector E111
terminals 3 and 4. Refer to AT- 1 6 9 , "
Wiring Diagram — AT — NON-
DTC" .
Check stop lamp switch after adjusting brake pedal — refer to
BR-7, "
BRAKE PEDAL" .
OK or NG
OK >> Check the following. If NG, repair or replace damaged
parts.
Harness for short or open between battery and stop lamp switch.
Harness for short or open between stop lamp switch and unified meter and A/C amp.
10 A fuse (No. 20, located in fuse block).
NG >> Repair or replace the stop lamp switch.
Item name Condition Display value
BRAKE SWDepressed brake pedal. ON
Released brake pedal. OFF
Item name Condition Display value
BRAKE SWDepressed brake pedal. ON
Released brake pedal. OFF
Condition Continuity
When brake pedal is depressed Yes
When brake pedal is released No
SCIA2126E