
Component Inspection " .
OK or NG OK >> GO TO 8.
NG >> Replace ASCD steering switch. .
>> INSPECTION END
Component Inspection INFOID:0000000004537421
ASCD STEERING SWITCH
1. Disconnect combination switch (spiral cable) harness connector M31.
2. Check continuity between combination switch (spiral cable) ter- minals 14 and 15 with pushing each switch.
If NG, replace ASCD steering switch. Switch Condition Resistance [
Ω]
MAIN switch Pressed Approx. 0
Released Approx. 4,000
CANCEL switch Pressed Approx. 250
Released Approx. 4,000
RESUME/ACCELERATE
switch Pressed Approx. 1,480
Released Approx. 4,000
SET/COAST switch Pressed Approx. 660
Released Approx. 4,000

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ASCD INDICATOR
Component Description INFOID:0000000004537517
ASCD indicator lamp illuminates to indicate ASCD operation status. Lamp has two indicators, CRUISE and
SET, and is integrated in combination meter.
CRUISE indicator illuminates when MAIN switch on ASCD st eering switch is turned ON to indicate that ASCD
system is ready for operation.
SET indicator illuminates when following conditions are met.
• CRUISE indicator is illuminated.
• SET/COAST switch on ASCD steering switch is tur ned ON while vehicle speed is within the range of ASCD
setting.
SET indicator remains lit during ASCD control.
Refer to EC-524 for the ASCD function.
CONSULT-III Reference Val ue in Data Monitor Mode INFOID:0000000004537518
Specification data are reference value.
MONITOR ITEM CONDITION SPECIFICATION
CRUISE LAMP • Ignition switch: ON MAIN switch: Pressed at 1st time
→ 2nd ON
→ OFF
SET LAMP • MAIN switch: ON
• Vehicle: Between 40 km/h (25 MPH) and 144 km/h (89 MPH) ASCD: Operating ON
ASCD: Not operating OFF
![NISSAN LATIO 2009 Service Repair Manual EC-1028< SERVICE INFOMATION >
[MR TYPE 2]
ENGINE CONTROL SYSTEM
*1: This sensor is not used to control the engine system under normal conditions.
*2: This signal is sent to the ECM through CAN communi NISSAN LATIO 2009 Service Repair Manual EC-1028< SERVICE INFOMATION >
[MR TYPE 2]
ENGINE CONTROL SYSTEM
*1: This sensor is not used to control the engine system under normal conditions.
*2: This signal is sent to the ECM through CAN communi](/manual-img/5/57359/w960_57359-2383.png)
EC-1028< SERVICE INFOMATION >
[MR TYPE 2]
ENGINE CONTROL SYSTEM
*1: This sensor is not used to control the engine system under normal conditions.
*2: This signal is sent to the ECM through CAN communication line.
*3: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
The amount of fuel injected from the fuel injector is determined by the ECM. The ECM controls the length of
time the valve remains open (injection pulse duration). T he amount of fuel injected is a program value in the
ECM memory. The program value is preset by engi ne operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from t he crankshaft position sensor (POS), camshaft position
sensor (PHASE) and the ma ss air flow sensor.
VARIOUS FUEL INJECTION I NCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compens ated to improve engine performance under various operat-
ing conditions as listed below.
• During warm-up
• When starting the engine
• During acceleration
• Hot-engine operation
• When selector lever is changed from N to D (A/T and CVT models)
• High-load, high-speed operation
• During deceleration
• During high engine speed operation
MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL) Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed*3
Piston position
Fuel injection
& mixture ratio
control Fuel injector
Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Park/neutral position (PNP) switch Gear position
Battery Battery voltage*3
Knock sensor Engine knocking condition
EPS control unit Power steering operation*2
Heated oxygen sensor 2* 1
Density of oxygen in exhaust gas
Air conditioner switch Air conditioner operation*2
ABS actuator and electric unit (control unit)
Vehicle speed*2
Combination meter PBIB3020E

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AUTOMATIC SPEED CONTROL DEVICE (ASCD)
System Description INFOID:0000000004499911
INPUT/OUTPUT SIGNAL CHART
*: This signal is sent to the ECM through CAN communication line.
BASIC ASCD SYSTEM Refer to Owner's Manual for ASCD operating instructions.
Automatic Speed Control Device (ASCD) allows a driver to keep vehicle at predetermined constant speed
without depressing accelerator pedal. Driver can set vehicle speed in advance between approximately 40 km/
h (25 MPH) and 144 km/h (89 MPH).
ECM controls throttle angle of electric thro ttle control actuator to regulate engine speed.
Operation status of ASCD is indicated by CRUISE i ndicator and SET indicator in combination meter. If any
malfunction occurs in ASCD system, it automatically deactivates control.
NOTE:
Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws.
SET OPERATION Press MAIN switch. (The CRUISE indicato r in combination meter illuminates.)
When vehicle speed reaches a desired speed between appr oximately 40 km/h (25 MPH) and 144 km/h (89
MPH), press SET/COAST switch. (Then SET indi cator in combination meter illuminates.)
ACCELERATE OPERATION If the RESUME/ACCELERATE switch is depressed during cruise control driving, increase the vehicle speed
until the switch is released or vehicle speed reaches maximum speed controlled by the system.
And then ASCD will keep the new set speed.
CANCEL OPERATION When any of following conditions exis t, cruise operation will be canceled.
• CANCEL switch is pressed
• More than two switches at ASCD steering switch are pressed at the same time (Set speed will be cleared)
• Brake pedal is depressed
• Clutch pedal is depressed or gear position is changed to the neutral position (M/T models)
• Selector lever is changed to N, P, R position (A/T and CVT models)
• Vehicle speed decreased to 13 km/h (8 MPH) lower than the set speed
When the ECM detects any of the following conditions, the ECM will cancel the cruise operation and inform
the driver by blinking indicator lamp.
• Engine coolant temperature is slightly higher than the normal operating temperature, CRUISE lamp may
blink slowly.
When the engine coolant temperature decreases to t he normal operating temperature, CRUISE lamp will
stop blinking and the cruise operation will be able to work by pressing SET/COAST switch or RESUME/
ACCELERATE switch.
• Malfunction for some self-diagnoses regarding ASCD control: SET lamp will blink quickly.
If MAIN switch is turned to OFF during ASCD is activated, all of ASCD operations will be canceled and vehicle
speed memory will be erased.
COAST OPERATION Sensor Input signal to ECM ECM function Actuator
ASCD brake switch Brake pedal operation
ASCD vehicle speed controlElectric throttle control
actuator
Stop lamp switch Brake pedal operation
ASCD clutch switch (M/T models) Clutch pedal operation
ASCD steering switch ASCD steering switch operation
Park/neutral position (PNP) switch Gear position
ABS actuator and electric unit (con-
trol unit) Vehicle speed*
Combination meter
TCM Powertrain revolution*
![NISSAN LATIO 2009 Service Repair Manual EC-1078< SERVICE INFOMATION >
[MR TYPE 2]
BASIC SERVICE PROCEDURE
BASIC SERVICE PROCEDURE
Basic Inspection INFOID:00000000044999291.
INSPECTION START
1. Check service records for any recent repairs th NISSAN LATIO 2009 Service Repair Manual EC-1078< SERVICE INFOMATION >
[MR TYPE 2]
BASIC SERVICE PROCEDURE
BASIC SERVICE PROCEDURE
Basic Inspection INFOID:00000000044999291.
INSPECTION START
1. Check service records for any recent repairs th](/manual-img/5/57359/w960_57359-2433.png)
EC-1078< SERVICE INFOMATION >
[MR TYPE 2]
BASIC SERVICE PROCEDURE
BASIC SERVICE PROCEDURE
Basic Inspection INFOID:00000000044999291.
INSPECTION START
1. Check service records for any recent repairs that ma y indicate a related malfunction, or a current need for
scheduled maintenance.
2. Open engine hood and check the following:
- Harness connectors for improper connections
- Wiring harness for improper connections, pinches and cut
- Vacuum hoses for splits, kinks and improper connections
- Hoses and ducts for leaks
- Air cleaner clogging
- Gasket
3. Confirm that electrical or mechanical loads are not applied.
- Headlamp switch is OFF.
- Air conditioner switch is OFF.
- Rear window defogger switch is OFF.
- Steering wheel is in the straight-ahead position, etc.
4. Start engine and warm it up until engine coolant temperature indicator points the middle of gauge.
Ensure engine stays below 1,000 rpm.
5. Run engine at about 2,000 rpm for about 2 minutes under no load.
6. Make sure that no DTC is displayed with CONSULT-III or GST.
OK or NG OK >> GO TO 3.
NG >> GO TO 2. 2.
REPAIR OR REPLACE
Repair or replace components as necessary according to corresponding Diagnostic Procedure.
>> GO TO 3. 3.
CHECK TARGET IDLE SPEED
With CONSULT-III
1. Run engine at about 2,000 rpm for about 2 minutes under no load. SEF983U
SEF976U
SEF977U
![NISSAN LATIO 2009 Service Repair Manual EC
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[Air conditioner, headlamp, rear window defogger]
On vehicles equipped with daytime light systems, if the parking brake is applied before the engine is
started the headlamp will not be illumi NISSAN LATIO 2009 Service Repair Manual EC
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[Air conditioner, headlamp, rear window defogger]
On vehicles equipped with daytime light systems, if the parking brake is applied before the engine is
started the headlamp will not be illumi](/manual-img/5/57359/w960_57359-2440.png)
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[Air conditioner, headlamp, rear window defogger]
On vehicles equipped with daytime light systems, if the parking brake is applied before the engine is
started the headlamp will not be illuminated.
• Steering wheel: Neutral (Straight-ahead position)
• Vehicle speed: Stopped
• Transmission: Warmed-up
- Models with CONSULT-III (A/T and CVT models)
• Drive vehicle until “FLUID TEMP SE” in “DATA MONI TOR” mode of “A/T” or “CVT” system indicates less
than 0.9V.
- Models without CONSULT-III (A/T and CVT models) and M/T models
• Drive vehicle for 10 minutes.
OPERATION PROCEDURE
With CONSULT-III
1. Perform EC-1084, " Accelerator Pedal Released Position Learning " .
2. Perform EC-1084, " Throttle Valve Closed Position Learning " .
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic PREP ARATION (previously mentioned) are in good order.
5. Select “IDLE AIR VOL LEA RN” in “WORK SUPPORT” mode.
6. Touch “START” and wait 20 seconds.
7. Make sure that “CMPLT” is displayed on CONSULT-III screen. If “CMPLT” is not displayed, Idle Air Vol-
ume Learning will not be carried out successfully. In this case, find the cause of the incident by referring to
the DIAGNOSTIC PROCEDURE below.
8. Rev up the engine two or three times and make sure that idle speed and ignition timing are within the specifications.
Refer to EC-1078, " Basic Inspection " .
Without CONSULT-III
NOTE:
• It is better to count the time accurately with a clock.
• It is impossible to switch the di agnostic mode when an accelerator pedal position sensor circuit has
a malfunction.
1. Perform EC-1084, " Accelerator Pedal Released Position Learning " .
2. Perform EC-1084, " Throttle Valve Closed Position Learning " .
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic PREP ARATION (previously mentioned) are in good order.
5. Turn ignition switch OFF and wait at least 10 seconds.
6. Confirm that accelerator pedal is fully releas ed, turn ignition switch ON and wait 3 seconds.
7. Repeat the following procedure quick ly five times within 5 seconds.
a. Fully depress the accelerator pedal.
b. Fully release the accelerator pedal.
8. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 20 seconds until the MIL stops
blinking and turned ON.
9. Fully release the accelerator pedal within 3 seconds after the MIL turned ON.
10. Start engine and let it idle.
![NISSAN LATIO 2009 Service Repair Manual TROUBLE DIAGNOSIS
EC-1105
< SERVICE INFOMATION >
[MR TYPE 2] C
D E
F
G H
I
J
K L
M A EC
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1. Stop lamp switch 2. ASCD brake switch 3. ASCD clutch switch
4. Clutch pedal 5. ASCD steering switch 6. NISSAN LATIO 2009 Service Repair Manual TROUBLE DIAGNOSIS
EC-1105
< SERVICE INFOMATION >
[MR TYPE 2] C
D E
F
G H
I
J
K L
M A EC
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1. Stop lamp switch 2. ASCD brake switch 3. ASCD clutch switch
4. Clutch pedal 5. ASCD steering switch 6.](/manual-img/5/57359/w960_57359-2460.png)
TROUBLE DIAGNOSIS
EC-1105
< SERVICE INFOMATION >
[MR TYPE 2] C
D E
F
G H
I
J
K L
M A EC
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1. Stop lamp switch 2. ASCD brake switch 3. ASCD clutch switch
4. Clutch pedal 5. ASCD steering switch 6. MAIN switch
7. CANCEL switch 8. SET/COAST switch 9. RESUME/ACCELERATOR switch
10. EVAP control system pressure sen- sor 11. EVAP canister 12. EVAP canister vent control valve BBIA0728E
![NISSAN LATIO 2009 Service Repair Manual EC
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: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.) 94 R ASCD steering switch
[Ignition switch: ON]
• ASCD steering switch: OFF Approximately 4V
[Ignit NISSAN LATIO 2009 Service Repair Manual EC
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: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.) 94 R ASCD steering switch
[Ignition switch: ON]
• ASCD steering switch: OFF Approximately 4V
[Ignit](/manual-img/5/57359/w960_57359-2470.png)
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: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.) 94 R ASCD steering switch
[Ignition switch: ON]
• ASCD steering switch: OFF Approximately 4V
[Ignition switch: ON]
• MAIN switch: Pressed Approximately 0V
[Ignition switch: ON]
• CANCEL switch: Pressed Approximately 1V
[Ignition switch: ON]
• RESUME/ACCELERATE switch: Pressed Approximately 3V
[Ignition switch: ON]
• SET/COAST switch: Pressed Approximately 2V
95 B Sensor ground
(ASCD steering switch) [Engine is running]
• Warm-up condition
• Idle speed Approximately 0V
99 R Stop lamp switch [Ignition switch: OFF]
• Brake pedal: Fully released Approximately 0V
[Ignition switch: OFF]
• Brake pedal: Slightly depressed BATTERY VOLTAGE
(11 - 14V)
100 G ASCD brake switch [Ignition switch: ON]
• Brake pedal: Slightly depressed (A/T, CVT)
• Brake pedal and/or clutch pedal: Slightly de-
pressed (M/T) Approximately 0V
[Ignition switch: ON]
• Brake pedal: Fully released (A/T, CVT)
• Brake pedal and clutch pedal: Fully re-
leased (M/T) BATTTERY VOLTAGE
(11 - 14V)
102 SB Sensor power supply
(Accelerator pedal position
sensor 2) [Ignition switch: ON]
Approximately 5V
103 GR Accelerator pedal position
sensor 2 [Ignition switch: ON]
• Engine stopped
• Accelerator pedal: Fully released 0.3 - 0.6V
[Ignition switch: ON]
• Engine stopped
• Accelerator pedal: Fully depressed 1.95 - 2.4V
104 Y Sensor ground
(Accelerator pedal position
sensor 2) [Engine is running]
• Warm-up condition
• Idle speed Approximately 0V
105 G Power supply for ECM [Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)
106 P Sensor power supply
(Accelerator pedal position
sensor 1) [Ignition switch: ON]
Approximately 5V
108 B ECM ground [Engine is running]
• Idle speed Body ground
110 G Accelerator pedal position
sensor 1 [Ignition switch: ON]
• Engine stopped
• Accelerator pedal: Fully released 0.6 - 0.9V
[Ignition switch: ON]
• Engine stopped
• Accelerator pedal: Fully depressed 3.9 - 4.7V
111 R Sensor ground
(Accelerator pedal position
sensor 1) [Engine is running]
• Warm-up condition
• Idle speed Approximately 0V
TERMI-
NAL
NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)