Nissan Tiida C11. Manual - part 845

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 Description

INFOID:0000000001682731

COMPONENT DESCRIPTION

PTC Control Unit

SJIA0968E

ALIIA0133GB

PTC HEATER CONTROL SYSTEM

HAC-45

< COMPONENT DIAGNOSIS >

[MANUAL AIR CONDITIONER]

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D

E

F

G

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J

K

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A

B

HAC

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P

The PTC control unit is attached on the A/C unit assembly. It controls
PTC heater by ambient temperature, and FAN ON signal.

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.

PTC HEATER (1500 WATT) : PTC Heater (1500 Watt) Diagnosis Procedure

INFOID:0000000001682732

DIAGNOSTIC PROCEDURE FOR PTC SYSTEM

SYMPTOM: PTC heater system operation is malfunction.

1.

CHECK POWER SUPPLY FOR BLOWER RELAY

1.

Turn ignition switch ON.

2.

Disconnect blower relay.

3.

Check voltage between blower relay harness connector J-1 ter-
minals 1, 5, and ground.

Is the inspection result normal

YES

>> GO TO 2.

NO

>> Repair harness or connector.

SJIA0906E

ALIIA0132ZZ

AWIIA0600ZZ

Terminals

Voltage

(Approx.)

(+)

(

−

)

Connector

Terminal

Ground

Battery voltage

Blower relay: J-1

1

5

WJIA1783E

HAC-46

< COMPONENT DIAGNOSIS >

[MANUAL AIR CONDITIONER]

PTC HEATER CONTROL SYSTEM

2.

CHECK BLOWER RELAY GROUND CIRCUIT 

1.

Turn ignition switch OFF.

2.

Check continuity between blower relay harness connector J-1
terminal 2 and ground.

Is the inspection result normal

YES

>> GO TO 3.

NO

>> Repair harness or connector.

3.

CHECK BLOWER RELAY

1.

Turn ignition switch OFF.

2.

Check blower relay. Refer to 

XX-XX, "*****"

.

Is the inspection result normal

YES

>> GO TO 4.

NO

>> Replace blower relay.

4.

CHECK POWER SUPPLY FOR PTC RELAY-1

1.

Turn ignition switch OFF.

2.

Reconnect blower relay.

3.

Turn ignition switch ON.

4.

Check voltage between PTC relay-1 harness connector E61 ter-
minals 2, 3, and ground.

Is the inspection result normal

YES

>> GO TO 5.

NO

>>

Check power supply circuit and 10A and 40A fuse (No. 16 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.

5.

CHECK POWER SUPPLY FOR PTC RELAY-2

Check voltage between PTC relay-2 harness connector E62 termi-
nals 2, 3, and ground.

Is the inspection result normal

YES

>> GO TO 6.

NO

>>

Check power supply circuit and 80A fuse (N, 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.

Connector

Terminal

Ground

Continuity

Blower relay: J-1

2

Yes

WJIA2264E

Terminals

Voltage

(Approx.)

(+)

(

−

)

Connector

Terminal

Ground

Battery voltage

PTC relay-2: E61

2

3

AWIIA0466ZZ

Terminals

Voltage

(Approx.)

(+)

(

−

)

Connector

Terminal

Ground

Battery voltage

PTC relay-2: E62

2

3

AWIIA0466ZZ

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

Terminals

Voltage

(Approx.)

(+)

(

−

)

Connector

Terminal

Ground

Battery voltage

PTC relay-3: E63

2

3

AWIIA0466ZZ

Connector

Terminal

Ground

Continuity

PTC relay-1: E61

1

Yes

AWIIA0455ZZ

A

B

Continuity

Connector

Terminal

Connector

Terminal

 PTC relay-1: E61

1

BCM: M19

64

Yes

AWIIA0467ZZ