Nissan Altima 2007-2012 Service Manual: Automatic speed control device (ASCD)

System Diagram

System Description


System Description

INPUT/OUTPUT SIGNAL CHART

*: This signal is sent to the ECM through CAN communication line


*: 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 throttle control actuator to regulate engine speed.

The ASCD operation status is indicated by two indicators (CRUISE and SET on the information display) on the combination meter. If any malfunction occurs in ASCD system, SET indicator blinks and ASCD control is deactivated.

NOTE: Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws.

SET OPERATION

Press MAIN switch. (CRUISE is indicated on the information display.) When vehicle speed reaches a desired speed between approximately 40 km/h (25 MPH) and 144 km/h (89 MPH), press SET/COAST switch. (Then SET is indicated on the information display.)

ACCELERATE OPERATION

If the RESUME/ACCELERATE switch is pressed 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 exist, cruise operation will be canceled.

• CANCEL switch is pressed

• More than 2 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 neutral position. (M/T models) • Selector lever is changed to N, P, R position (CVT models) • Vehicle speed decreased to 13 km/h (8 MPH) lower than the set speed

• TCS system is operated When the ECM detects any of the following conditions, the ECM will cancel the cruise operation and inform the driver by blinking indicators.

• Engine coolant temperature is slightly higher than the normal operating temperature, CRUISE indicator may blink slowly.

When the engine coolant temperature decreases to the normal operating temperature, CRUISE indicator 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 indicator 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

When the SET/COAST switch is pressed during cruise control driving, decrease vehicle set speed until the switch is released. And then ASCD will keep the new set speed.

RESUME OPERATION

When the RESUME/ACCELERATE switch is pressed after cancel operation other than pressing MAIN switch is performed, vehicle speed will return to last set speed. To resume vehicle set speed, vehicle condition must meet following conditions.

• Brake pedal is released

• Clutch pedal is released (M/T models) • Selector lever is in other than P and N positions (CVT models) • Vehicle speed is greater than 40 km/h (25 MPH) and less than 144 km/h (89 MPH)

Component Parts Location

1. Intake valve timing control solenoid


1. Intake valve timing control solenoid valve

2. Ignition coil (with power transistor) and spark plug

3. Knock sensor, Crankshaft position sensor (POS)

4. Air fuel ratio (A/F) sensor 1

5. Camshaft position sensor (PHASE)

6. Engine coolant temperature sensor

7. Park/neutral position (PNP) switch

8. ECM

9. Refrigerant pressure sensor

10. Battery current sensor

11. IPDM E/R

12. Mass air flow sensor (with intake temperature sensor)

13. EVAP service port

14. Electric throttle control actuator (with built in throttle position sensor and throttle control motor)

15. EVAP canister purge volume control solenoid valve

16. Fuel injector

17. Power steering pressure sensor

1. Battery


1. Battery

2. Fuel pump fuse (15A)

3. IPDM E/R

4. Brake master cylinder

5. Engine ground

6. Air cleaner assembly

7. Mass air flow sensor (with intake air temperature sensor)

8. Radiator hose (upper)

9. Engine coolant temperature sensor

10. Intake air duct

11. Camshaft position sensor (PHASE)

12. Tie rod (RH)

13. Power steering pressure sensor

14. Knock sensor

15. Engine oil cooler

16. Crankshaft position sensor (POS)

17. Drive shaft (RH)

1. Exhaust manifold cover


1. Exhaust manifold cover

2. Air fuel ratio (A/F) sensor 1

3. Heated oxygen sensor 2 (This illustration is a view from under vehicle.)

4. Engine oil pan

1. EVAP service port


1. EVAP service port

2. Intake air duct

3. EVAP canister purge volume control solenoid valve

4. Intake manifold collector

5. Park/neutral position (PNP) switch (CVT) (This illustration is view with air cleaner assembly removed.)

6. Park/neutral position (PNP) switch (M/T) (This illustration is view with air cleaner assembly removed.)

7. Intake valve timing control solenoid valve (This illustration is view with engine removed.)

8. Exhaust manifold cover

9. Air fuel ratio (A/F) sensor 1

10. Air fuel ratio (A/F) sensor 1 harness connector

11. Heated oxygen sensor 2 (This illustration is view from under vehicle.)

12. Heated oxygen sensor 2 harness connector (This illustration is view from under vehicle.)

13. Engine oil pan

1. Throttle valve


1. Throttle valve (This illustration is view with intake air duct removed.)

2. Electric throttle control actuator

3. Fuel injector harness connector

4. Condenser-2

5. Radiator hose (upper)

6. Battery

7. ECM

8. Fuel level sensor unit and fuel pump harness connector (This illustration is view with rear seat cushion and inspection hole cover removed.)

9. Fuel level sensor unit and fuel pump assembly

10. Fuel pressure regulator

11. Fuel tank temperature sensor

12. EVAP control system pressure sensor (This illustration is view with rear suspension member removed.)

13. EVAP canister vent control valve (This illustration is view with rear suspension member removed.)

14. EVAP canister (This illustration is view with rear suspension member removed.)

1. No.1 ignition coil


1. No.1 ignition coil

2. Cooling fan motor-1 harness connector

3. Cooling fan motor-2 harness connector

4. Refrigerant pressure sensor

5. Accelerator pedal position sensor

6. ASCD brake switch

7. Stop lamp switch

8. Brake pedal

9. ASCD clutch switch

10. Clutch pedal

11. ASCD steering switch

12. CANSEC switch

13. RESUME/ACCELERATE switch

14. SET/COAST switch

15. MAIN switch

Component Description


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