2007 NISSAN TIIDA EC Engine Control System

HA-26
< ON-VEHICLE MAINTENANCE >
ELECTRICAL LEAK DETECTOR
2. Connect a suitable A/C manifold gauge set to the A/C service ports.
3. Check if the A/C refrigerant pressure is at least 345 kPa (3.45 bar, 3.52 kg/cm
2, 50 psi) above 16°C. If less
than specification, recover/evacuate and recharge the system with the specified amount of refrigerant.
NOTE:
At temperatures below 16°C, leaks may not be detected since the system may not reach 345 kPa (3.45
bar, 3.52 kg/cm
2, 50 psi).
4. Perform the leak test from the high-pressure side (compressor discharge a to evaporator inlet f) to the
low-pressure side (evaporator drain hose g to shaft seal k). Refer to HA-27, "
Component". Perform a leak
check for the following areas carefully. Clean the component to be checked and move the leak detected
probe completely around the connection/component.
 Compressor
Check the fitting of high- and low-pressure flexible hoses, relief valve and shaft seal.
 Condenser
Check the fitting of high-pressure flexible hose and pipe, refrigerant pressure sensor.
 Liquid tank
Check the refrigerant connection.
 Service valves
Check all around the service valves. Ensure service valve caps are secured on the service valves (to
prevent leaks).
NOTE:
After removing A/C manifold gauge set from service valves, wipe any residue from valves to prevent any
false readings by leak detector.
 Cooling unit (Evaporator)
With engine OFF, turn blower fan on “High” for at least 15 seconds to dissipate any refrigerant trace in
the cooling unit. Wait a minimum of 10 minutes accumulation time (refer to the manufacturer’s recom-
mended procedure for actual wait time) before inserting the leak detector probe into the drain hose.
Keep the probe inserted for at least 10 seconds. Use caution not to contaminate the probe tip with water
or dirt that may be in the drain hose.
5. If a leak detector detects a leak, verify at least once by blowing compressed air into area of suspected
leak, then repeat check as outlined above.
6. Do not stop when one leak is found. Continue to check for additional leaks at all system components.
If no leaks are found, perform steps 7-10.
7. Start engine.
8. Set the heater A/C control as follows;
a. A/C switch: ON
b. Mode control dial position: VENT (Ventilation)
c. Intake door lever position: Recirculation
d. Max. cold temperature
e. Fan speed: High
9. Run engine at 1,500 rpm for at least 2 minutes.
10. Turn engine off and perform leak check again following steps 4
through 6 above.
Refrigerant leaks should be checked immediately after stopping
the engine. Begin with the leak detector at the compressor. The
pressure on the high-pressure side will gradually drop after
refrigerant circulation stops and pressure on the low-pressure
side will gradually rise, as shown in the graph. Some leaks are
more easily detected when pressure is high.
11. Before connecting recovery/recycling equipment to vehicle,
check recovery/recycling equipment gauges. No refrigerant
pressure should be displayed. If pressure is displayed, recover
refrigerant from equipment lines.
12. Discharge A/C system using approved refrigerant recovery/recycling equipment. Repair the leaking fitting
or component if necessary.
13. Evacuate and recharge A/C system and perform the leak test to confirm no refrigerant leaks.
14. Perform A/C performance test to ensure system works properly.
SHA839E

HAC-6
< BASIC INSPECTION >[MANUAL AIR CONDITIONER]
INSPECTION AND ADJUSTMENT
INSPECTION AND ADJUSTMENT
Operational CheckINFOID:0000000001203052
The purpose of the operational check is to confirm that the system operates properly.
CHECKING BLOWER
1. Turn blower control dial clockwise to "1" position. Blower should operate on low speed.
2. Turn blower control dial clockwise to "2" position, and continue checking blower speed until all speeds are
checked.
3. Leave blower on Maximum speed.
If NG, go to trouble diagnosis procedure for xxx BLOWER MOTOR CIR HAC-19, "
Front Blower Motor Diagno-
sis Procedure".
If OK, continue the check.
CHECKING DISCHARGE AIR
1. Turn mode door control dial to each position.
2. Confirm that discharge air comes out according to the air distribution table. Refer to XXXX DISCHARGE
AIR FLOW.
If NG, go to trouble diagnosis procedure for HAC-16, "
Mode Door Diagnostic Procedure".
If OK, continue the check.
CHECKING RECIRCULATION
1. Set intake door lever to REC position.
2. Operate intake door lever to FRE position.
3. Listen for intake door position change (you should hear blower sound change slightly).
If NG, go to trouble diagnosis procedure for XXXX INTAKE DOOR.
If OK, continue the check.
CHECKING TEMPERATURE DECREASE
1. Turn temperature control dial counterclockwise to full cold position.
2. Check for cold air at discharge air outlets.
If NG, go to trouble diagnosis procedure for XXXX INSUFFICIENT COOLING.
If OK, continue the check.
CHECKING TEMPERATURE INCREASE
1. Turn temperature control dial clockwise to full hot position.
2. Check for hot air at discharge air outlets.
If NG, go to trouble diagnosis procedure for XXXX INSUFFICIENT HEATING.
If OK, continue the check.
CHECKING A/C SWITCH (IF EQUIPPED)
1. Turn fan control dial to the desired (1 to 4 speed) position.
2. Press A/C switch.
3. A/C switch indicator will turn ON.
• Confirm that the compressor clutch engages (sound or visual inspection).
If NG, go to trouble diagnosis procedure for XXXX MAG CLUTCH CIR.
If OK, continue the check.
CHECKING DEFROST A/C SWITCH (IF EQUIPPED)
1. Turn fan control dial to the desired (1 to 4 speed) position.
2. Turn mode dial to ( ) DEF.
3. Confirm that the compressor clutch engages (sound or visual inspection). Conditions : Engine running at normal operating temperature

PTC HEATER CONTROL SYSTEM
HAC-33
< COMPONENT DIAGNOSIS >[MANUAL AIR CONDITIONER]
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PTC HEATER CONTROL SYSTEM
PTC HEATER (300 WATT)
PTC HEATER (300 WATT) : PTC Heater System DescriptionINFOID:0000000001674171
SYSTEM DESCRIPTION
The PTC heater system is controlled by ambient temperature, water temperature, FAN ON signal and temper-
ature control dial. Hot air is supplied to a discharge air outlet by PTC heater that generates heat electrically
even when engine coolant temperature is low.
Component Parts
PTC heater system components are:
 PTC control unit
 PTC heater
PTC relay-1
 Water temperature sensor
 Full hot switch
 Ambient sensor
System Operation
PTC heater system starts when all the following conditions are met:
 Less than 35 minutes after ignition switch ON.
 Blower control dial ON (Blower motor operates.) and temperature control dial full hot position (Full hot switch
ON).
 Ambient temperature is lower than 0°C (32°F).
 Engine coolant temperature is lower than 65°C (149°F) (condition
1), or when it becomes lower than 60°C (140°F) again (condition 2)
on startup.
 Engine speed is more than 1100 rpm and after a lapse of more
than 10 seconds.
PTC heater system stops when any of the following conditions is
met:
 More than 35 minutes later after ignition switch ON.
 Blower control dial OFF (Blower motor OFF) and/or temperature
control dial except full hot position (Full hot switch OFF).
 Ambient temperature is higher than 0°C (32°F).
 Engine coolant temperature is higher than 65°C (149°F).
 When engine speed becomes less than 800 rpm.
SJIA0968E
AWIIA0354GB

PTC HEATER CONTROL SYSTEM
HAC-35
< COMPONENT DIAGNOSIS >[MANUAL AIR CONDITIONER]
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The full hot switch is attached on the A/C unit assembly. When the
temperature control dial at full hot position, and then full hot switch
turned ON.
PTC HEATER (300 WATT) : PTC Heater (300 Watt) Diagnosis ProcedureINFOID:0000000001674173
DIAGNOSTIC PROCEDURE FOR PTC SYSTEM
SYMPTOM: PTC heater system operation is malfunction.
1.CHECK POWER SUPPLY FOR PTC RELAY-1
1. Turn ignition switch ON.
2. Check voltage between PTC relay-1 harness connector E61 ter-
minals 2, 3, and ground.
Is the inspection result normal
YES >> GO TO 2.
NO >> Check power supply circuit and 10A fuse and 40A fusible link (No. 2 and I, located in the fuse
block). Refer to XX.
 If fuses are OK, check harness for open circuit. Repair or replace if necessary.
 If fuses are NG, replace fuse and check harness for short circuit. Repair or replace if necessary.
2.CHECK PTC RELAY-1
1. Turn ignition switch OFF.
2. Check PTC relay-1. Refer to HAC-41, "
PTC HEATER (300 WATT) : PTC Heater (300 Watt) Component
Inspection".
Is the inspection result normal
YES >> GO TO 3.
NO >> Replace PTC relay-1. Refer to XX.
3.CHECK PTC RELAY-1 OUTPUT CIRCUIT
1. Disconnect ambient sensor, PTC heater and water temperature
sensor connectors.
2. Turn temperature control dial clockwise until full hot position.
3. Turn mode control dial to foot position.
4. Start the engine.
5. Turn blower control dial to maximum speed.
6. Check resistance between PTC relay-1 harness connector E61
terminal 1 and ground.
Is the inspection result normal
YES >> GO TO 5.
SJIA0909E
Te r m i n a l s
Vo l ta g e
(Approx.)
(+) (−)
Connector Terminal
Ground Battery voltage
PTC relay-1: E612
3
SJIA0913E
Connector Terminal
GroundContinuity
PTC relay-1: E61 1 Yes
AWIIA0455ZZ

HAC-40
< COMPONENT DIAGNOSIS >[MANUAL AIR CONDITIONER]
PTC HEATER CONTROL SYSTEM
19.CHECK CIRCUIT CONTINUITY BETWEEN AMBIENT TEMPERATURE SENSOR AND PTC CONTROL
UNIT
Check continuity between ambient temperature sensor harness con-
nector M60 (A) terminal 3 and PTC control unit harness connector
M84 (B) terminal 8.
Is the inspection result normal
YES >> 1. If equipped with manual transmission, GO TO 20.
2. If equipped with automatic transmission, GO TO 22.
NO >> Repair harness or connector.
20.CHECK ENGINE RPM SIGNAL (MANUAL TRANSMISSION)
1. Reconnect PTC control unit.
2. Start the engine.
3. Check voltage between PTC control unit harness connector
M84 terminal 4 and ground.
Is the inspection result normal
YES >> GO TO 22.
NO >> GO TO 21.
21.CHECK CONTINUITY OF ENGINE RPM CIRCUIT BETWEEN FRONT AIR CONNTROL AND PTC CON-
TROL UNIT (MANUAL TRANSMISSION)
1. Turn ignition switch OFF.
2. Disconnect ECM and PTC control unit connector.
3. Check continuity between PTC control unit harness connector
M84 (A) terminal 4 and ECM harness connector F10 (B) termi-
nal 13.
4. Check continuity between PTC control unit harness connector
M84 (A) terminal 4 and ground.
Is the inspection result normal
YES >> Replace ECM. Refer to XX.
NO >> Repair harness or connector.
22.CHECK BCM INPUT (FAN ON) SIGNAL
AB
Continuity
Connector Terminal Connector Terminal
Ambient temperature
sensor: M643PTC control unit:
M848Yes
AWIIA0464ZZ
Te r m i n a l s
Vo l ta g e
(Approx.) (+) (−)
Connector Terminal
Ground
PTC control unit: M84 4 4.2V
SJIA0924E
AB
Continuity
Connector Terminal Connector Terminal
PTC control unit: M84 4 ECM: F10 13 Yes
A
GroundContinuity
Connector Terminal
PTC control unit: M84 4 No
SJIA0925E

PTC HEATER CONTROL SYSTEM
HAC-43
< COMPONENT DIAGNOSIS >[MANUAL AIR CONDITIONER]
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After disconnecting full hot switch connector M65, check continuity
between terminals 1 and 2 at switch side.
If NG, replace full hot switch. Refer to XX.
PTC relay-1
Check continuity between terminal Nos. 3 and 5.
If NG, replace PTC relay-1. Refer to XX.
PTC HEATER (1500 WATT)
PTC HEATER (1500 WATT) : System DescriptionINFOID:0000000001682730
SYSTEM DESCRIPTION
The PTC heater system is controlled by ambient temperature, water temperature, FAN ON signal. Hot air is
supplied to a discharge air outlet by PTC heater that generates heat electrically even when engine coolant
temperature is low.
Component Parts
PTC heater system components are: PTC control unit
Connector Terminals Condition Continuity
Full hot switch:
M6512Temperature control dial:
Full hot positionYe s
Temperature control dial:
Except full hot positionNo
SJIA0930E
Condition Continuity
12V direct current supply between terminal Nos. 1 and 2 Yes
No current supply No
SJIA0931E

HAC-44
< COMPONENT DIAGNOSIS >[MANUAL AIR CONDITIONER]
PTC HEATER CONTROL SYSTEM
 PTC heater
PTC relays
 Ambient sensor
 Blower relay
System Operation
PTC heater system starts when all the following conditions are met:
 Less than 35 minutes after ignition switch ON.
 Blower control dial ON (Blower motor operates.)
 Ambient temperature is lower than 0°C (32°F).
 Engine coolant temperature is lower than 65°C (149°F) (condition
1), or when it becomes lower than 60°C (140°F) again (condition 2)
on startup.
 Engine speed is more than 1100 rpm and after a lapse of more
than 10 seconds.
PTC heater system stops when any of the following conditions is
met:
 More than 35 minutes later after ignition switch ON.
 Fan control dial OFF (Blower motor OFF).
 Ambient temperature is higher than 0°C (32°F).
 Engine coolant temperature is higher than 65°C (149°F).
 When engine speed becomes less than 800 rpm.
PTC HEATER (1500 WATT) : Component DescriptionINFOID:0000000001682731
COMPONENT DESCRIPTION
PTC Control Unit
SJIA0968E
ALIIA0133GB

PTC HEATER CONTROL SYSTEM
HAC-47
< COMPONENT DIAGNOSIS >[MANUAL AIR CONDITIONER]
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6.CHECK POWER SUPPLY FOR PTC RELAY-3
Check voltage between PTC relay-3 harness connector E61 termi-
nals 2, 3, and ground.
Is the inspection result normal
YES >> GO TO 5.
NO >> Check power supply circuit and 80A fuse (P, located in the fuse block). Refer to XX-XX.
 If fuses are OK, check harness for open circuit. Repair or replace if necessary.
 If fuses are NG, replace fuse and check harness for short circuit. Repair or replace if necessary.
7.CHECK PTC RELAYS
1. Turn ignition switch OFF.
2. Check PTC relay. Refer to XX-XX, "*****"
.
Is the inspection result normal
YES >> GO TO 6.
NO >> Replace inoperative PTC relay.
8.CHECK PTC RELAY-1 GROUND CIRCUIT
1. Disconnect ambient sensor, and PTC heater connectors.
2. Turn temperature control dial clockwise until full hot position.
3. Turn mode control dial to foot position.
4. Start the engine (1,000 RPM minimum).
5. Turn blower control dial to low speed.
6. Check continuity between PTC relay-1 harness connector E61
terminal 1 and ground.
Is the inspection result normal
YES >> GO TO 10.
NO >> GO TO 9.
9.CHECK CIRCUIT CONTINUITY BETWEEN PTC RELAY-1 AND BCM
1. Turn ignition switch OFF.
2. Disconnect BCM connector.
3. Check continuity between PTC relay-1 harness connector E61
(A) terminal 1 and BCM harness connector M19 (B) terminal 64.
Is the inspection result normal
YES >> Replace BCM. Refer to XXXX.
NO >> Repair harness or connector.
10.CHECK PTC RELAY-2 GROUND CIRCUIT
Te r m i n a l s
Vo l ta g e
(Approx.)
(+) (−)
Connector Terminal
Ground Battery voltage
PTC relay-3: E632
3
AWIIA0466ZZ
Connector Terminal
GroundContinuity
PTC relay-1: E61 1 Yes
AWIIA0455ZZ
AB
Continuity
Connector Terminal Connector Terminal
PTC relay-1: E61 1 BCM: M19 64 Yes
AWIIA0467ZZ