Air Conditioning System (For Manual Air Conditioning System) Ptc Heater Circuit


DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK VEHICLE TYPE

INSPECT PTC HEATER RELAY (PTC NO.1, PTC NO.2, PTC NO.3)

CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY

CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 3 RELAY BLOCK - AIR CONDITIONING AMPLIFIER)

CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 3 RELAY BLOCK - QUICK HEATER)

CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 3 RELAY BLOCK - BATTERY AND BODY GROUND)

INSPECT QUICK HEATER ASSEMBLY

CHECK HARNESS AND CONNECTOR (QUICK HEATER - BODY GROUND)

INSPECT PTC HEATER RELAY (PTC HTR NO.1, PTC HTR NO.2, PTC HTR NO.3)

CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY

CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 1 RELAY BLOCK, JUNCTION BLOCK - AIR CONDITIONING AMPLIFIER)

CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 1 RELAY BLOCK, JUNCTION BLOCK - QUICK HEATER)

CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 1 RELAY BLOCK, JUNCTION BLOCK - BATTERY AND BODY GROUND)

INSPECT QUICK HEATER ASSEMBLY

CHECK HARNESS AND CONNECTOR (QUICK HEATER - BODY GROUND)

AIR CONDITIONING SYSTEM (for Manual Air Conditioning System) - PTC Heater Circuit


DESCRIPTION

PTC heater relays are closed in accordance with signals from the air conditioning amplifier assembly and power is supplied to the quick heater assembly installed on the radiator heater unit.

WIRING DIAGRAM


Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Heating Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System).Air Conditioning System (For Manual Air Conditioning System) Ptc Heater Circuit


INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
1.CHECK VEHICLE TYPE

  1. Check the vehicle type.

    Result
    Result
    		Proceed to
    w/o Urea SCR System
    		A
    w/ Urea SCR System
    		B


B
Go to step 9
A


2.INSPECT PTC HEATER RELAY (PTC NO.1, PTC NO.2, PTC NO.3)


    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155

  1. Remove the PTC NO.1, PTC NO.2 and PTC NO.3 relays from the engine room No. 3 relay block.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    3 - 5
    		Battery voltage is not applied to terminals 1 and 2
    		10 kΩ or higher
    Battery voltage is applied to terminals 1 and 2
    		Below 1 Ω


NG
REPLACE PTC HEATER RELAY (PTC NO.1, PTC NO.2, PTC NO.3)
OK


3.CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY


    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Heating Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System).Air Conditioning System (For Manual Air Conditioning System) Ptc Heater Circuit

  1. Remove the air conditioning amplifier assembly with its connectors still connected (LandCruiser RM0000039R5028X.html).

  1. Measure the voltage according to the value(s) in the table below.

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    G25-3 (PTC1) - Body ground
    1. Engine running (1250 rpm or more)
    2. Temperature setting MAX HOT
    3. Outside temperature 10°C (50°F) or less
    4. Engine coolant temperature 79°C (174°F) or less
    5. Headlight dimmer switch off
    6. Blower switch off
    		11 to 14 V
    G25-22 (PTC2) - Body ground
    1. Engine running (1250 rpm or more)
    2. Temperature setting MAX HOT
    3. Outside temperature 10°C (50°F) or less
    4. Engine coolant temperature 76°C (169°F) or less
    5. Headlight dimmer switch off
    6. Blower switch off
    G25-4 (PTC3) - Body ground
    1. Engine running (1250 rpm or more)
    2. Temperature setting MAX HOT
    3. Outside temperature 10°C (50°F) or less
    4. Engine coolant temperature 73°C (163°F) or less
    5. Headlight dimmer switch off
    6. Blower switch off
    G25-3 (PTC1) - Body ground
    1. Engine running (1250 rpm or more)
    2. Temperature setting MAX HOT
    3. Outside temperature 10°C (50°F) or less
    4. Engine coolant temperature 79°C (174°F) or less
    5. Headlight dimmer switch off
    6. Blower switch on
    		Below 1 V
    G25-22 (PTC2) - Body ground
    1. Engine running (1250 rpm or more)
    2. Temperature setting MAX HOT
    3. Outside temperature 10°C (50°F) or less
    4. Engine coolant temperature 76°C (169°F) or less
    5. Headlight dimmer switch off
    6. Blower switch on
    G25-4 (PTC3) - Body ground
    1. Engine running (1250 rpm or more)
    2. Temperature setting MAX HOT
    3. Outside temperature 10°C (50°F) or less
    4. Engine coolant temperature 73°C (163°F) or less
    5. Headlight dimmer switch off
    6. Blower switch on
    Text in Illustration
    *a
    		Component with harness connected
    (Air Conditioning Amplifier Assembly)


NG
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE (LandCruiser RM0000045EC00TX.html)
OK


4.CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 3 RELAY BLOCK - AIR CONDITIONING AMPLIFIER)

  1. Remove the PTC heater relays from the engine room No. 3 relay block.

  1. Disconnect the G25 amplifier connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    PTC NO.1 relay terminal 1 - G25-3 (PTC1)
    		Always
    		Below 1 Ω
    PTC NO.2 relay terminal 1 - G25-22 (PTC2)
    PTC NO.3 relay terminal 1 - G25-4 (PTC3)
    PTC NO.1 relay terminal 1 - Body ground
    		Always
    		10 kΩ or higher
    PTC NO.2 relay terminal 1 - Body ground
    PTC NO.3 relay terminal 1 - Body ground


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


5.CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 3 RELAY BLOCK - QUICK HEATER)

  1. Remove the PTC heater relays from the engine room No. 3 relay block.

  1. Disconnect the G28 quick heater connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    PTC NO.1 relay terminal 3 - G28-2 (B)
    		Always
    		Below 1 Ω
    PTC NO.2 relay terminal 3 - G28-3 (B)
    PTC NO.3 relay terminal 3 - G28-1 (B)
    PTC NO.1 relay terminal 3 - Body ground
    		Always
    		10 kΩ or higher
    PTC NO.2 relay terminal 3 - Body ground
    PTC NO.3 relay terminal 3 - Body ground


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


6.CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 3 RELAY BLOCK - BATTERY AND BODY GROUND)


    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Heating Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System).Air Conditioning System (For Manual Air Conditioning System) Ptc Heater Circuit

  1. Remove the PTC heater relays from the engine room No. 3 relay block.

  1. Measure the voltage according to the value(s) in the table below.

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    PTC NO.1 relay terminal 5 - Body ground
    		Always
    		11 to 14 V
    PTC NO.2 relay terminal 5 - Body ground
    PTC NO.3 relay terminal 5 - Body ground

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    PTC NO.1 relay terminal 2 - Body ground
    		Always
    		Below 1 Ω
    PTC NO.2 relay terminal 2 - Body ground
    PTC NO.3 relay terminal 2 - Body ground
Text in Illustration
*1
PTC NO.1 Relay
*2
PTC NO.2 Relay
*3
PTC NO.3 Relay
*a
Component without relay installed
(Engine Room No. 3 Relay Block)


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


7.INSPECT QUICK HEATER ASSEMBLY

  1. Remove the quick heater assembly (LandCruiser RM0000022AH02QX.html).

  1. Inspect the quick heater assembly (LandCruiser RM0000022AG026X.html).



NG
REPLACE QUICK HEATER ASSEMBLY (LandCruiser RM0000022AH02QX.html)
OK


8.CHECK HARNESS AND CONNECTOR (QUICK HEATER - BODY GROUND)


    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Heating Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System).Air Conditioning System (For Manual Air Conditioning System) Ptc Heater Circuit

  1. Disconnect the G178 and G179 heater connectors.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    G178-1 (E) - Body ground
    		Always
    		Below 1 Ω
    G179-1 (E) - Body ground
    Text in Illustration
    *a
    		Front view of wire harness connector
    (to Quick Heater Assembly)


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE (LandCruiser RM0000045EC00TX.html)

9.INSPECT PTC HEATER RELAY (PTC HTR NO.1, PTC HTR NO.2, PTC HTR NO.3)


    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155

  1. Remove the PTC HTR NO.1, PTC HTR NO.2 and PTC HTR NO.3 relays from the engine room No. 1 relay block, junction block.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    3 - 5
    		Battery voltage is not applied to terminals 1 and 2
    		10 kΩ or higher
    Battery voltage is applied to terminals 1 and 2
    		Below 1 Ω


NG
REPLACE PTC HEATER RELAY (PTC HEATER RELAY (PTC HTR NO.1, PTC HTR NO.2, PTC HTR NO.3))
OK


10.CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY


    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Heating Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System).Air Conditioning System (For Manual Air Conditioning System) Ptc Heater Circuit

  1. Remove the air conditioning amplifier assembly with its connectors still connected (LandCruiser RM0000039R5028X.html).

  1. Measure the voltage according to the value(s) in the table below.

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    G25-3 (PTC1) - Body ground
    1. Engine running (1250 rpm or more)
    2. Temperature setting MAX HOT
    3. Outside temperature 10°C (50°F) or less
    4. Engine coolant temperature 79°C (174°F) or less
    5. Headlight dimmer switch off
    6. Blower switch off
    		11 to 14 V
    G25-22 (PTC2) - Body ground
    1. Engine running (1250 rpm or more)
    2. Temperature setting MAX HOT
    3. Outside temperature 10°C (50°F) or less
    4. Engine coolant temperature 76°C (169°F) or less
    5. Headlight dimmer switch off
    6. Blower switch off
    G25-4 (PTC3) - Body ground
    1. Engine running (1250 rpm or more)
    2. Temperature setting MAX HOT
    3. Outside temperature 10°C (50°F) or less
    4. Engine coolant temperature 73°C (163°F) or less
    5. Headlight dimmer switch off
    6. Blower switch off
    G25-3 (PTC1) - Body ground
    1. Engine running (1250 rpm or more)
    2. Temperature setting MAX HOT
    3. Outside temperature 10°C (50°F) or less
    4. Engine coolant temperature 79°C (174°F) or less
    5. Headlight dimmer switch off
    6. Blower switch on
    		Below 1 V
    G25-22 (PTC2) - Body ground
    1. Engine running (1250 rpm or more)
    2. Temperature setting MAX HOT
    3. Outside temperature 10°C (50°F) or less
    4. Engine coolant temperature 76°C (169°F) or less
    5. Headlight dimmer switch off
    6. Blower switch on
    G25-4 (PTC3) - Body ground
    1. Engine running (1250 rpm or more)
    2. Temperature setting MAX HOT
    3. Outside temperature 10°C (50°F) or less
    4. Engine coolant temperature 73°C (163°F) or less
    5. Headlight dimmer switch off
    6. Blower switch on
    Text in Illustration
    *a
    		Component with harness connected
    (Air Conditioning Amplifier Assembly)


NG
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE (LandCruiser RM0000045EC00TX.html)
OK


11.CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 1 RELAY BLOCK, JUNCTION BLOCK - AIR CONDITIONING AMPLIFIER)

  1. Remove the PTC heater relays from the engine room No. 1 relay block, junction block.

  1. Disconnect the G25 amplifier connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    PTC HTR NO.1 relay terminal 1 - G25-3 (PTC1)
    		Always
    		Below 1 Ω
    PTC HTR NO.2 relay terminal 1 - G25-22 (PTC2)
    PTC HTR NO.3 relay terminal 1 - G25-4 (PTC3)
    PTC HTR NO.1 relay terminal 1 - Body ground
    		Always
    		10 kΩ or higher
    PTC HTR NO.2 relay terminal 1 - Body ground
    PTC HTR NO.3 relay terminal 1 - Body ground


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


12.CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 1 RELAY BLOCK, JUNCTION BLOCK - QUICK HEATER)

  1. Remove the PTC heater relays from the engine room No. 1 relay block, junction block.

  1. Disconnect the G28 quick heater connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    PTC HTR NO.1 relay terminal 3 - G28-2 (B)
    		Always
    		Below 1 Ω
    PTC HTR NO.2 relay terminal 3 - G28-3 (B)
    PTC HTR NO.3 relay terminal 3 - G28-1 (B)
    PTC HTR NO.1 relay terminal 3 - Body ground
    		Always
    		10 kΩ or higher
    PTC HTR NO.2 relay terminal 3 - Body ground
    PTC HTR NO.3 relay terminal 3 - Body ground


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


13.CHECK HARNESS AND CONNECTOR (ENGINE ROOM NO. 1 RELAY BLOCK, JUNCTION BLOCK - BATTERY AND BODY GROUND)


    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Heating Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System).Air Conditioning System (For Manual Air Conditioning System) Ptc Heater Circuit

  1. Remove the PTC heater relays from the engine room No. 1 relay block, junction block.

  1. Measure the voltage according to the value(s) in the table below.

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    PTC HTR NO.1 relay terminal 5 - Body ground
    		Always
    		11 to 14 V
    PTC HTR NO.2 relay terminal 5 - Body ground
    PTC HTR NO.3 relay terminal 5 - Body ground

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    PTC HTR NO.1 relay terminal 2 - Body ground
    		Always
    		Below 1 Ω
    PTC HTR NO.2 relay terminal 2 - Body ground
    PTC HTR NO.3 relay terminal 2 - Body ground
Text in Illustration
*1
PTC HTR NO.1 Relay
*2
PTC HTR NO.2 Relay
*3
PTC HTR NO.3 Relay
*a
Component without relay installed
(Engine Room No. 1 Relay Block, Junction Block)


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


14.INSPECT QUICK HEATER ASSEMBLY

  1. Remove the quick heater assembly (LandCruiser RM0000022AH02QX.html).

  1. Inspect the quick heater assembly (LandCruiser RM0000022AG026X.html).



NG
REPLACE QUICK HEATER ASSEMBLY (LandCruiser RM0000022AH02QX.html)
OK


15.CHECK HARNESS AND CONNECTOR (QUICK HEATER - BODY GROUND)


    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Heating Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System).Air Conditioning System (For Manual Air Conditioning System) Ptc Heater Circuit

  1. Disconnect the G178 and G179 heater connectors.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    G178-1 (E) - Body ground
    		Always
    		Below 1 Ω
    G179-1 (E) - Body ground
    Text in Illustration
    *a
    		Front view of wire harness connector
    (to Quick Heater Assembly)


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE (LandCruiser RM0000045EC00TX.html)