Nissan Altima (L32) 2007-2012 Service Manual: Cooling fan control

System Diagram

System Description

INPUT/OUTPUT SIGNAL CHART

*1: The ECM determines the start signal status by the signals of engine speed and battery voltage.

*2: This signal is sent to ECM via the CAN communication line.

SYSTEM DESCRIPTION

The ECM controls the cooling fan corresponding to the vehicle speed, engine coolant temperature, refrigerant pressure, and air conditioner ON signal. The control system has 4-step control [HIGH/MIDDLE/LOW/OFF].

Cooling Fan Operation

Cooling Fan Relay Operation

The ECM controls cooling fan relays in the IPDM E/R via the CAN communication line.

Component Parts Location

1. Power valve actuator 1

2. Intake valve timing control solenoid valve (bank 1)

3. Power steering pressure sensor

4. Intake valve timing control solenoid valve (bank 2)

5. VIAS control solenoid valves 1 and 2

6. Fuel injector (bank 2)

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

8. Crankshaft position sensor (POS)

9. Engine coolant temperature sensor

10. Camshaft position sensor (PHASE) (bank 2)

11. ECM

12. Refrigerant pressure sensor

13. Battery current sensor

14. PNP switch

15. Condenser-2

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

17. EVAP service port

18. Camshaft position sensor (PHASE) (bank 1)

19. Electric throttle control actuator

20. Power valve actuator 2

21. EVAP canister purge volume control solenoid valve

22. Ignition coil (with power transistor) and spark plug (bank 1)

23. Knock sensor

1. Mas air flow sensor (with intake air temperature sensor)

2. Air cleaner case

3. Engine coolant temperature sensor

4. EVAP canister purge volume control solenoid valve

5. Power valve actuator 1

6. VIAS control solenoid valve 1

7. VIAS control solenoid valve 2

8. Power valve actuator 2

9. Power steering pressure sensor

10. Tie rod (RH)

11. Power valve actuator 2

12. Camshaft position sensor (PHASE) (bank 1)

13. Camshaft position sensor (PHASE) (bank 2)

1. A/F sensor 1 (bank 1)

2. A/F sensor 1 (bank 2)

3. HO2S2 (bank 1) harness connector

4. HO2S2 (bank 2) harness connector (CVT models)

5. Front engine mount

6. HO2S2 (bank 2) harness connector (M/T models)

7. Crankshaft position sensor (POS) (M/T models)

8. Crankshaft position sensor (POS) (CVT models)

1. Electronic controlled engine mount control solenoid valve

2. EVAP control system pressure sensor

3. EVAP canister vent control valve

4. EVAP canister

5. Injector harness connector

6. Intake valve timing control solenoid valve (bank 1)

7. Intake valve timing control solenoid valve (bank 2)

1. Knock sensor (bank 2)

2. Knock sensor (bank 1)

3. PNP switch (CVT models)

4. PNP switch (M/T models)

5. Battery

6. IPDM E/R

7. ECM

8. Refrigerant pressure sensor (shown with front grill removed)

9. Accelerator pedal

1. ASCD brake switch

2. Stop lamp switch

3. Brake pedal

4. ASCD steering switch

5. ASCD clutch switch (M/T models)

6. Clutch pedal

Component Description