HAC-142
< COMPONENT DIAGNOSIS >[AUTO AIR CONDITIONER (W/O NAVI)]
PTC HEATER CONTROL SYSTEM
PTC HEATER CONTROL SYSTEM
PTC HEATER (300 WATT)
PTC HEATER (300 WATT) : PTC Heater System DescriptionINFOID:0000000001682706
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 the discharge air outlets by a PTC heater that generates heat electri-
cally 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°).
Engine coolant temperature is lower than 65°C (149°) (condition
1), or when it becomes lower than 60°C (140°) 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°).
Engine coolant temperature is higher than 65°C (149°).
When engine speed becomes less than 800 rpm.
SJIA0968E
AWIIA0343GB
HAC-144
< COMPONENT DIAGNOSIS >[AUTO AIR CONDITIONER (W/O NAVI)]
PTC HEATER CONTROL SYSTEM
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 front air control.
PTC HEATER (300 WATT) : PTC Heater (300 Watt) Diagnosis ProcedureINFOID:0000000001682708
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 (No. 2) and 40A fusible link (No. I), located in the fuse
and fusible link box.
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-151, "
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 continuity between PTC relay-1 harness connector E61
terminal 1 and ground.
Is the inspection result normal
YES >> GO TO 5.
AWIIA0600ZZ
Te r m i n a l s
Voltag e
(Approx.)
(+) (−)
Connector Terminal
Ground Battery voltage
PTC relay-1: E612
3
SJIA0913E
Connector Terminal
GroundContinuity
PTC relay-1: E61 1 Yes
AWIIA0455ZZ
HAC-150
< COMPONENT DIAGNOSIS >[AUTO AIR CONDITIONER (W/O NAVI)]
PTC HEATER CONTROL SYSTEM
Is the inspection result normal?
YES >> 1. Replace front air control. Refer to XX.
2. Go to self-diagnosis HAC-213, "
Front Air Control Self-Diagnosis" and perform self-diagnosis
STEP-2. Confirm that code No. 20 is displayed.
NO >> Repair harness or connector.
22.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 24.
NO >> GO TO 23.
23.CHECK CONTINUITY OF ENGINE RPM CIRCUIT BETWEEN FRONT AIR CONTROL 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.
24.CHECK BCM INPUT (FAN ON) SIGNAL
A
GroundContinuity
Connector Terminal
Ambient sensor:
E602No
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-153
< COMPONENT DIAGNOSIS >[AUTO AIR CONDITIONER (W/O NAVI)]
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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.
PTC relay
Check continuity between terminal Nos. 3 and 5.
If NG, replace PTC relay.
PTC HEATER (1500 WATT)
PTC HEATER (1500 WATT) : System DescriptionINFOID:0000000001682723
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
Terminals Condition Continuity
12Temperature 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-154
< COMPONENT DIAGNOSIS >[AUTO AIR CONDITIONER (W/O NAVI)]
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:0000000001682724
COMPONENT DESCRIPTION
PTC Control Unit
SJIA0968E
ALIIA0133GB
PTC HEATER CONTROL SYSTEM
HAC-157
< COMPONENT DIAGNOSIS >[AUTO AIR CONDITIONER (W/O NAVI)]
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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
HAC-160
< COMPONENT DIAGNOSIS >[AUTO AIR CONDITIONER (W/O NAVI)]
PTC HEATER CONTROL SYSTEM
Refer to XX-XX, "*****".
Is the inspection result normal?
YES >> GO TO 18.
NO >> Replace ambient temperature sensor. Refer to XX.
18.CHECK PTC HEATER RELAY-1 POWER SUPPLY CIRCUIT
1. Disconnect PTC heater connector.
2. Reconnect all PTC relays.
3. Start the engine (1,000 RPM minimum).
4. Check voltage between PTC heater harness connector E65 ter-
minal 3 and ground.
Is the inspection result normal?
YES >> GO TO 19.
NO >> Repair harness or connector.
19.CHECK PTC HEATER RELAY-2 POWER SUPPLY CIRCUIT
Check voltage between PTC heater harness connector E65 terminal
2 and ground.
Is the inspection result normal
YES >> GO TO 20.
NO >> Repair harness or connector.
20.CHECK PTC HEATER RELAY-3 POWER SUPPLY CIRCUIT
Check voltage between PTC heater harness connector E65 terminal
1 and ground.
Is the inspection result normal
YES >> Replace PTC heater. Refer to XXXX.
NO >> Repair harness or connector.
PTC HEATER (1500 WATT) : PTC Heater (1500 Watt) Component Inspection
INFOID:0000000001682726
COMPONENT INSPECTION
Blower Relay
Te r m i n a l s
Vol tag e
(Approx.) (+) (−)
Connector Terminal
Ground
PTC heater: E65 3 Battery voltage
AWIIA0472ZZ
Te r m i n a l s
Vol tag e
(Approx.) (+) (−)
Connector Terminal
Ground
PTC heater: E65 2 Battery voltage
AWIIA0474ZZ
Te r m i n a l s
Vol tag e
(Approx.) (+) (−)
Connector Terminal
Ground
PTC heater: E65 1 Battery voltage
AWIIA0476ZZ
INSUFFICIENT COOLING
HAC-189
< SYMPTOM DIAGNOSIS >[AUTO AIR CONDITIONER (W/O NAVI)]
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Testing must be performed as follows:
Test ReadingINFOID:0000000001547455
TEST READING
Recirculating-to-discharge Air Temperature Table
Ambient Air Temperature-to-operating Pressure Table
*1: In the motor fan low-speed control
*2: In the motor fan high-speed control
Trouble Diagnoses for Unusual PressureINFOID:0000000001547456
TROUBLE DIAGNOSIS FOR UNUSUAL PRESSURE
Vehicle condition Indoors or in the shade (in a well-ventilated place)
Doors Closed
Door window Open
Hood Open
TEMP. Max. COLD
Mode switch
(Ventilation) set
Recirculation (REC) switch
(Recirculation) set
Fan (blower) speedMax. speed set
Engine speed Idle speed
Operate the air conditioning system for 10 minutes before taking measurements.
Inside air (Recirculating air) at blower assembly inlet
Discharge air temperature at center ventilator
°C (°F) Relative humidity
%Air temperature
°C (°F)
50 - 6020 (68) 7.2 - 9.1 (45 - 48)
25 (77) 11.4 - 13.8 (53 - 57)
30 (86) 15.5 - 18.4 (60 - 65)
35 (95) 20.3 - 23.7 (69 - 75)
60 - 7020 (68) 9.1 - 10.9 (48 - 52)
25 (77) 13.8 - 16.2 (57 - 61)
30 (86) 18.4 - 21.3 (65 - 70)
35 (95) 23.7 - 27.1 (75 - 81)
Ambient air
High-pressure (Discharge side)
kPa (bar, kg/cm
2, psi)Low-pressure (Suction side)
kPa (bar, kg/cm2, psi) Relative humidity
%Air temperature
°C (°F)
50 - 7020 (68)843 - 1,036 *1
(11.08 - 13.63, 8.6 - 10.6, 122 - 150)159.0 - 194.0
(1.59 - 1.94, 1.62 - 1.98, 23.1 - 28.1)
25 (77)1,094 - 1,338 *1
(10.94 - 13.38, 11.2 - 13.6, 159 - 194)196.3 - 240.0
(1.96 - 2.40, 2.00 - 2.45, 28.5 - 34.8)
30 (86)1,298 - 1,590 *1
(12.98 - 15.90, 13.2 - 16.2, 188 - 231)248.0 - 302.7
(2.48 - 3.03, 2.53 - 3.09, 36.0 - 43.9)
35 (95)1,383 - 1,688 *2
(13.83 - 16.88, 14.1 - 17.2, 201 - 245)308.8 - 377.4
(3.09 - 3.77, 3.15 - 3.85, 44.8 - 54.7)
40 (104)1,628 - 1,988 *2
(16.28 - 19.88, 16.6 - 20.3, 236 - 288)377.4 - 461.2
(3.77 - 4.61, 3.85 - 4.70, 54.7 - 66.8)