2007 NISSAN TIIDA sensor

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

HAC-34
< COMPONENT DIAGNOSIS >[MANUAL AIR CONDITIONER]
PTC HEATER CONTROL SYSTEM
PTC HEATER (300 WATT) : PTC Heater Component Description
INFOID:0000000001674172
COMPONENT DESCRIPTION
PTC Control Unit
The PTC control unit is attached on the A/C unit assembly. It controls
PTC heater by ambient temperature, water temperature, FAN ON
signal and temperature control dial.
PTC Heater
The PTC heater is attached on the A/C unit assembly. It generates
heat electrically.
Ambient Sensor
The ambient sensor is attached on the radiator core support upper. It
detects ambient temperature and converts it into a resistance value
which is then input into the PTC control unit.
Water Temperature Sensor
The water temperature sensor is attached on heater pipe. It detects
water temperature and converts it into a resistance value which is
then input in to PTC control unit.
Full Hot Switch
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SJIA0907E
AWIIA0600ZZ
SJIA0908E

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.
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Te r m i n a l s
Vo l ta g e
(Approx.)
(+) (−)
Connector Terminal
Ground Battery voltage
PTC relay-1: E612
3
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Connector Terminal
GroundContinuity
PTC relay-1: E61 1 Yes
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HAC-38
< COMPONENT DIAGNOSIS >[MANUAL AIR CONDITIONER]
PTC HEATER CONTROL SYSTEM
Check full hot switch. Refer to HAC-41, "PTC HEATER (300 WATT) : PTC Heater (300 Watt) Component
Inspection".
Is the inspection result normal
YES >> Replace the PTC control unit. Refer to XX.
NO >> Replace full hot switch. Refer to XX.
12.CHECK VOLTAGE BETWEEN WATER TEMPERATURE SENSOR AND GROUND
Check voltage between water temperature sensor harness connec-
tor M64 terminal 1 and ground.
Is the inspection result normal
YES >> GO TO 14.
NO >> GO TO 13.
13.CHECK CIRCUIT CONTINUITY BETWEEN WATER TEMPERATURE SENSOR AND PTC CONTROL
UNIT
1. Turn ignition switch OFF.
2. Disconnect PTC control unit.
3. Check continuity between water temperature sensor harness
connector M64 (A) terminal 1 and PTC control unit harness con-
nector M84 (B) terminal 9.
4. Check continuity between water temperature sensor harness
connector M64 (A) terminal 1 and ground.
Is the inspection result normal
YES >> Replace PTC control unit. Refer to XX.
NO >> Repair harness or connector.
14.CHECK WATER TEMPERATURE SENSOR
Refer to HAC-41, "
PTC HEATER (300 WATT) : PTC Heater (300 Watt) Component Inspection".
Is the inspection result normal
YES >> GO TO 15.
NO >> Replace water temperature sensor. Refer to XX.
15.CHECK CIRCUIT CONTINUITY BETWEEN WATER TEMPERATURE SENSOR AND PTC CONTROL
UNIT
Te r m i n a l s
Vo l ta g e
(Approx.)
(+) (−)
Connector Terminal
Ground 5V
Water temperature sensor:
M641
SJIA0920E
AB
Continuity
Connector Terminal Connector Terminal
Water temperature
sensor: M641PTC control
unit: M849Yes
A
Continuity
Connector Terminal
Water temperature sensor: M64 1 Ground No
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PTC HEATER CONTROL SYSTEM
HAC-39
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Check continuity between water temperature sensor harness con-
nector M64 (A) terminal 2 and PTC control unit harness connector
M84 (B) terminal 8.
Is the inspection result normal
YES >> GO TO 16.
NO >> Repair harness or connector.
16.CHECK VOLTAGE BETWEEN AMBIENT TEMPERATURE SENSOR AND GROUND
1. Reconnect PTC control unit connector.
2. Turn ignition switch ON.
3. Check voltage between ambient temperature sensor harness
connector M60 terminal 4 and ground.
Is the inspection result normal
YES >> GO TO 18.
NO >> GO TO 17.
17.CHECK CIRCUIT CONTINUITY BETWEEN AMBIENT TEMPERATURE SENSOR AND PTC CONTROL
UNIT
1. Turn ignition switch OFF.
2. Check continuity between ambient temperature sensor harness
connector M60 (A) terminal 4 and PTC control unit harness con-
nector M84 (B) terminal 10.
3. Check continuity between ambient temperature sensor harness
connector E60 (A) terminal 4 and ground.
Is the inspection result normal
YES >> Replace PTC control unit. Refer to XXXX.
NO >> Repair harness or connector.
18.CHECK AMBIENT TEMPERATURE SENSOR
Refer to HAC-245, "
Ambient Sensor Component Inspection".
Is the inspection result normal
YES >> GO TO 19.
NO >> Replace ambient temperature sensor. Refer to XX.
AB
Continuity
Connector Terminal Connector Terminal
Water temperature
sensor: M642PTC control unit:
M848Yes
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Te r m i n a l s
Vol tag e
(Approx.) (+) (−)
Connector Terminal
Ground
Ambient temperature sen-
sor: M6045V
AWIIA0462ZZ
AB
Continuity
Connector Terminal Connector Terminal
Ambient temperature
sensor: E604PTC control
unit: M8410 Yes
A
GroundContinuity
Connector Terminal
Ambient temperature sensor: E60 4 No
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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
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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-41
< COMPONENT DIAGNOSIS >[MANUAL AIR CONDITIONER]
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1. Turn blower control dial to "1" position.
2. Confirm fan on signal between PTC control unit harness con-
nector M84 terminal 11 and ground using oscilloscope.
Is the inspection result normal
YES >> Replace PTC control unit.
NO >> GO TO 23.
23.CHECK CIRCUIT CONTINUITY BETWEEN BCM AND PTC CONTROL UNIT
1. Turn ignition switch OFF.
2. Disconnect BCM connector and PTC control unit connector.
3. Check continuity between BCM harness connector M19 (A) ter-
minal 50 and PTC control unit harness connector M84 (B) ter-
minal 11.
4. Check continuity between PTC control unit harness connector
M84 (A) terminal 11 and ground.
Is the inspection result normal
YES >> Replace BCM. Refer to XX.
NO >> Repair harness or connector.
PTC HEATER (300 WATT) : PTC Heater (300 Watt) Component Inspection
INFOID:0000000001674174
COMPONENT INSPECTION
Ambient Sensor
Te r m i n a l s
Vo l ta g e
(Approx.) (+)
(-)
Connector Terminal
PTC control
unit: M8411 Ground
AWIIA0460ZZ
ZJIA0583J
AB
Continuity
Connector Terminal Connector Terminal
BCM: M19 50PTC control unit:
M8411 Ye s
A
GroundContinuity
Connector Terminal
PTC control unit: M84 11 No
AWIIA0461ZZ

HAC-42
< COMPONENT DIAGNOSIS >[MANUAL AIR CONDITIONER]
PTC HEATER CONTROL SYSTEM
After disconnecting ambient sensor connector E60, measure resis-
tance between terminals 3 and 4 at sensor side, using the table
below.
If NG, replace ambient sensor. Refer to XX.
Water Temperature Sensor
After disconnecting water temperature sensor connector M64, mea-
sure resistance between terminals 1 and 2 at sensor side, using the
table below.
If NG, replace water temperature sensor. Refer to XX.
Full Hot Switch
Temperature °C (°F) Resistance kΩ
−15 (5) 12.73
−10 (14) 9.92
−5 (23) 7.80
0 (32) 6.19
5 (41) 4.95
10 (50) 3.99
15 (59) 3.24
20 (68) 2.65
25 (77) 2.19
30 (86) 1.81
35 (95) 1.51
40 (104) 1.27
45 (113) 1.07
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Temperature °C (°F) Resistance kΩ
−20 (−4) 31.62
−10 (14) 17.47
0 (32) 10.09
10 (50) 6.05
20 (68) 3.76
30 (86) 2.41
40 (104) 1.59
50 (122) 1.08
60 (140) 0.75
70 (158) 0.53
80 (176) 0.38
90 (194) 0.28
100 (212) 0.21
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