EC-618
DTC P1572 ASCD BRAKE SWITCH
Revision: 2006 November2007 350Z
8. CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector.
3. Check voltage between stop lamp switch terminal 3 and ground
with CONSULT-III or tester.
OK or NG
OK >> GO TO 10.
NG >> GO TO 9.
9. DETECT MALFUNCTIONING PART
Check the following.
Fuse block (J/B) connector E101
10A fuse
Harness for open or short between stop lamp switch and battery
>> Repair open circuit or short to ground or short to power in harness or connectors.
10. CHECK STOP LAMP SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 122 and stop lamp switch terminal 4.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 12.
NG >> GO TO 11.
11 . DETECT MALFUNCTIONING PART
Check the following.
Harness connectors E108, M15
Harness for open or short between ECM and stop lamp switch
>> Repair open circuit or short to ground or short to power in harness or connectors.
PBIB1089E
Voltage: Battery voltage
PBIB2309E
Continuity should exist.
DTC P1572 ASCD BRAKE SWITCH
EC-621
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Revision: 2006 November2007 350Z
4. CHECK ASCD BRAKE SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ASCD brake switch harness connector.
3. Turn ignition switch ON.
4. Check voltage between ASCD brake switch terminal 1 and
ground with CONSULT-III or tester.
OK or NG
OK >> GO TO 6.
NG >> GO TO 5.
5. DETECT MALFUNCTIONING PART
Check the following.
Fuse block (J/B) connector E101
10A fuse
Harness for open or short between ASCD brake switch and fuse
>> Repair open circuit or short to ground or short to power in harness or connectors.
6. CHECK ASCD BRAKE SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Check harness continuity between ASCD brake switch terminal 2 and ASCD clutch switch terminal 1.
Refer to Wiring Diagram.
3. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
7. CHECK ASCD BRAKE SWITCH
Refer to EC-624, "
Component Inspection"
OK or NG
OK >> GO TO 16.
NG >> Replace ASCD brake switch.
PBIB1282E
Voltage: Battery voltage
PBIB0857E
Continuity should exist.
EC-622
DTC P1572 ASCD BRAKE SWITCH
Revision: 2006 November2007 350Z
8. CHECK ASCD CLUTCH SWITCH INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between ASCD clutch switch terminal 2 and ECM terminal 126.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 10.
NG >> GO TO 9.
9. DETECT MALFUNCTIONING PART
Check the following.
Harness connectors E108, M15
Harness for open or short between ECM and ASCD clutch switch
>> Repair open circuit or short to ground or short to power in harness or connectors.
10. CHECK ASCD CLUTCH SWITCH
Refer to EC-624, "
Component Inspection" .
OK or NG
OK >> GO TO 16.
NG >> Replace ASCD clutch switch.
11 . CHECK STOP LAMP SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect stop lamp switch harness connector.
3. Check voltage between stop lamp switch terminal 3 and ground
with CONSULT-III or tester.
OK or NG
OK >> GO TO 13.
NG >> GO TO 12.Continuity should exist.
PBIB1282E
Voltage: Battery voltage
PBIB2309E
DTC P1574 ASCD VEHICLE SPEED SENSOR
EC-625
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Revision: 2006 November2007 350Z
DTC P1574 ASCD VEHICLE SPEED SENSORPFP:31036
Component DescriptionNBS000G7
The ECM receives two vehicle speed sensor signals via CAN communication line. One is sent from “unified
meter and A/C amp.”, and the other is from TCM (Transmission control module). The ECM uses these signals
for ASCD control. Refer to EC-30, "
AUTOMATIC SPEED CONTROL DEVICE (ASCD)" for ASCD functions.
On Board Diagnosis LogicNBS000G8
This self-diagnosis has the one trip detection logic.
The MIL will not light up for this self-diagnosis.
NOTE:
If DTC P1574 is displayed with DTC U1000 or U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-151, "
DTC U1000, U1001 CAN COMMUNICATION LINE" .
If DTC P1574 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010.
Refer to EC-154, "
DTC U1010 CAN COMMUNICATION" .
If DTC P1574 is displayed with DTC P0500, first perform the trouble diagnosis for DTC P0500.
Refer to EC-496, "
DTC P0500 VSS"
If DTC P1574 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605.
Refer to EC-512, "
DTC P0605 ECM"
DTC Confirmation ProcedureNBS000G9
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Step 3 may be conducted with the drive wheels lifted in the shop or by driving the vehicle. If a road test
is expected to be easier, it is unnecessary to lift the vehicle.
WITH CONSULT-III
1. Start engine (VDC switch or TCS switch OFF).
2. Select “DATA MONITOR” mode with CONSULT-III.
3. Drive the vehicle at more than 40 km/h (25 MPH).
4. Check DTC.
5. If DTC is detected, go to EC-626, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III” above.
DTC No.Trouble Diagnosis
NameDTC Detecting Condition Possible Cause
P1574
1574ASCD vehicle speed
sensorECM detects a difference between two vehicle
speed signals is out of the specified range.
Harness or connectors
(The CAN communication line is open or
shorted.)
Unified meter and A/C amp.
VDC/TCS/ABS control unit
(with VDC models)
ABS actuator and electric unit (control unit)
(without VDC models)
Wheel sensor
TCM(A/T models)
ECM
EC-628
DTC P1805 BRAKE SWITCH
Revision: 2006 November2007 350Z
DTC P1805 BRAKE SWITCHPFP:25320
DescriptionNBS000GI
Brake switch signal is applied to the ECM through the stop lamp switch when the brake pedal is depressed.
This signal is used mainly to decrease the engine speed when the vehicle is driving.
CONSULT-III Reference Value in Data Monitor ModeNBS000GJ
Specification data are reference values.
On Board Diagnosis LogicNBS000GK
The MIL will not light up for this self-diagnosis.
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode.
DTC Confirmation ProcedureNBS000GL
WITH CONSULT-III
1. Turn ignition switch ON.
2. Fully depress the brake pedal for at least 5 seconds.
3. Erase the DTC with CONSULT-III.
4. Check 1st trip DTC.
5. If 1st trip DTC is detected, go to EC-630, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III” above.
MONITOR ITEM CONDITION SPECIFICATION
BRAKE SW
Ignition switch: ONBrake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1805
1805Brake switchA brake switch signal is not sent to ECM for
extremely long time while the vehicle is driving.
Harness or connectors
(The stop lamp switch circuit is open or
shorted.)
Stop lamp switch
Engine operating condition in fail-safe mode
ECM controls the electric throttle control actuator by regulating the throttle opening to a small range.
Therefore, acceleration will be poor.
Vehicle condition Driving condition
When engine is idling Normal
When accelerating Poor acceleration
EC-640
DTC P2122, P2123 APP SENSOR
Revision: 2006 November2007 350Z
Component InspectionNBS000GV
ACCELERATOR PEDAL POSITION SENSOR
1. Reconnect all harness connectors disconnected.
2. Turn ignition switch ON.
3. Check voltage between ECM terminals 97 (APP sensor 1 sig-
nal), 98 (APP sensor 2 signal) and ground under the following
conditions.
4. If NG, replace accelerator pedal assembly and go to next step.
5. Perform EC-77, "
Accelerator Pedal Released Position Learning" .
6. Perform EC-77, "
Throttle Valve Closed Position Learning" .
7. Perform EC-77, "
Idle Air Volume Learning" .
Removal and InstallationNBS000GW
ACCELERATOR PEDAL
Refer to ACC-3, "ACCELERATOR CONTROL SYSTEM" .
Terminal Accelerator pedal Voltage
97
(Accelerator pedal position
sensor 1)Fully released 0.5 - 1.0V
Fully depressed 3.9 - 4.7V
98
(Accelerator pedal position
sensor 2)Fully released 0.15 - 0.60V
Fully depressed 1.95 - 2.40V
PBIB3582E
EC-648
DTC P2127, P2128 APP SENSOR
Revision: 2006 November2007 350Z
9. CHECK APP SENSOR 2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 98 and APP sensor terminal 2.
Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 11.
NG >> GO TO 10.
10. DETECT MALFUNCTIONING PART
Check the following.
Harness connectors E108, M15
Harness for open or short between ECM and APP sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
11 . CHECK APP SENSOR
Refer to EC-658, "
Component Inspection" .
OK or NG
OK >> GO TO 13.
NG >> GO TO 12.
12. REPLACE ACCELERATOR PEDAL ASSEMBLY
1. Replace accelerator pedal assembly.
2. Perform EC-77, "
Accelerator Pedal Released Position Learning" .
3. Perform EC-77, "
Throttle Valve Closed Position Learning" .
4. Perform EC-77, "
Idle Air Volume Learning" .
>>INSPECTION END
13. CHECK INTERMITTENT INCIDENT
Refer to EC-141, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT" .
>>INSPECTION END
Component InspectionNBS000H3
ACCELERATOR PEDAL POSITION SENSOR
1. Reconnect all harness connectors disconnected.
2. Turn ignition switch ON.
3. Check voltage between ECM terminals 97 (APP sensor 1 sig-
nal), 98 (APP sensor 2 signal) and ground under the following
conditions.Continuity should exist.
Terminal Accelerator pedal Voltage
97
(Accelerator pedal position
sensor 1)Fully released 0.5 - 1.0V
Fully depressed 3.9 - 4.7V
98
(Accelerator pedal position
sensor 2)Fully released 0.15 - 0.60V
Fully depressed 1.95 - 2.40V
PBIB3582E
DTC P2138 APP SENSOR
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Revision: 2006 November2007 350Z
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureNBS000HG
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 8V at idle.
WITH CONSULT-III
1. Start engine and let it idle for 1 second.
2. Check DTC.
3. If DTC is detected, go to EC-654, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-III” above.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2138
2138Accelerator pedal posi-
tion sensor circuit
range/performanceRationally incorrect voltage is sent to ECM
compared with the signals from APP sensor 1
and APP sensor 2.
Harness or connector
(The APP sensor 1 and 2 circuit is open
or shorted.)
Harness or connectors
(APP sensor 2 dircuit is open or
shorted.)
[CKP sensor (POS) circuit is open or
shorted.]
[CMP sensor (PHASE) (bank 2) circuit is
shorted.]
[EVT control position sensor (bank 2) cir-
cuit is shorted.]
(EVAP control system pressure sensor
circuit is shorted.)
(Refrigerant pressure sensor circuit is
shorted.)
Accelerator pedal position sensor
(APP sensor 1 and 2)
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)
(bank 2)
Exhaust valve timing control position
sensor (bank 2)
EVAP control system pressure sensor
Refrigerant pressure sensor
Engine operating condition in fail-safe mode
The ECM controls the electric throttle control actuator in regulating the throttle opening in order for the idle position to be within +10
degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal condition.
So, the acceleration will be poor.