2005 TOYOTA AVENSIS heater

I22120
Condition: Air conditioning system does not function. (Sometimes it may function)
I22121
Condition : Air conditioning system does not function effectively.
± HEATER & AIR CONDITIONERREFRIGERANT
55±35
AVENSIS REPAIR MANUAL (RM1018E)
(5) When the refrigerant does not circulate:
SymptomProbable causeDiagnosisCorrective Actions

Vacuum is indicated on low pres-
sure side, and extreamly low pres-
sure is indicated on high pressure
side

Frost or dew is seen on piping on
both sides of condenser or refrig-
erant filter

Refrigerant flow is obstructed by
moisture or dirt in refrigeration sys-
tem

Refrigerant filter is clogged
Refrigerant does not circulate
(1) Check the refrigerant filter
(2) Clean out dirt on refrigerant fil-
ter by blowing air
(3) Replace condenser
(4) Vacuum air and supply proper
amount of new refrigerant
(5) If refrigerant filter is damaged,
replace it
(6) When the refrigerant is overcharged or cooling of
condenser is insufficient:
SymptomProbable causeDiagnosisRemedy

Pressure is extreamly high on
both low and high pressure sides
Excessive refrigerant

Cooling performance of con-
denser is insufficient
Excessive refrigerant

Cooling performance of con-
denser is insufficient

Magnet valve assy is defective
(1) Clean condenser fins
(2) Check condenser fan motor
operation
(3) If (1) and (2) are in normal
state, vacuum and supply proper
amount of refrigerant
(4) If pressure is still high even af-
ter supplying refrigerant, replace
the magnet valve assy

I22122
Condition
NOTE : These gauge indica-
tions occur when the refrigera-
tion system opens and the re-
frigerant is charged without
vacuuming. : Air conditioning system does not function.
I22123
Condition : Air conditioning system does not function effectively. 55±36
± HEATER & AIR CONDITIONERREFRIGERANT
AVENSIS REPAIR MANUAL (RM1018E)
(7) When there is air in the refrigeration system:
SymptomProbable causeDiagnosisCorrective Actions
Pressure is extreamly high on both
low and the high pressure sidesAir in refrigeration system

There is air in refrigeration sys-
tem

Vacuuming is insufficient(1) Check if compressor oil is dirty
or insufficient
(2) Vacuum air and supply new re-
frigerant
(8) When the refrigerant filter is defective:
SymptomProbable causeDiagnosisCorrective Actions

Pressure is extreamly high on
low pressure side

Pressure is extreamly high on
high pressure side
Trouble with refrigerant filterExcessive refrigerantReplace refrigerant filter

I22124
Condition : Air conditioning system does not function.
I22123
Condition: Air conditioning system does not function effectively.
± HEATER & AIR CONDITIONERREFRIGERANT
55±37
AVENSIS REPAIR MANUAL (RM1018E)
(9) When the compressor is defective:
SymptomProbable causeDiagnosisCorrective Actions

Pressure is extreamly high on
low pressure side

Pressure is extreamly low on
high pressure side
Internal leak from compressor

Compression failure

Leakage from damaged valve or
broken sliding parts
Replace or replace compressor
(10) When the magnet valve assy is defective:
SymptomProbable causeDiagnosisCorrective Actions

Pressure is extreamly high on
low pressure sideInternal leak from magnet valve
assyMagnet valve assy failureReplace magnet valve assy

550ZJ±01
I36136
I32396
E
IN
IG
± HEATER & AIR CONDITIONERHOT GAS TYPE POWER HEATER SYSTEM
55±23
AVENSIS REPAIR MANUAL (RM1018E)
INSPECTION
1. INSPECT W/RECEIVER CONDENSER ASSY
(a) Apply voltage between terminals and check that the re-
frigerant passages switch.
2. INSPECT HETER SWITCH ASSY
(a) Check that the continuity to the follwing terminals.
Standard:
Heater switch conditionConnecting terminalsStandard value
ONIG ± INContinuity
OFFIG ± INNo continuity
ONIG ± EContinuity
OFFIG ± ENo continuity

550ZI±01
I35437
Connector ºBº Wire harness side:
Connector ºAº
I36091
Connector ºBº From back side:
Connector ºAº 55±22
± HEATER & AIR CONDITIONERHOT GAS TYPE POWER HEATER SYSTEM
AVENSIS REPAIR MANUAL (RM1018E)
HOT GAS TYPE POWER HEATER SYSTEM
ON±VEHICLE INSPECTION
1. INSPECT AIR CONDITIONING CONTROL ASSY
(a) Disconnect the connector from air conditioning control assy and inspect the connector on wire harness
side, as shown in the table.
Symbols (Terminal No.)Wiring ColorConditionSTD Voltage (V)
SOL+ (B17) ±
GND (B40)R ± W±BStart engine
Compressor: OperatePulse generation
MGV (B14) ±
GND (B40) (*1)R±Y ± W±BStart engine
Compressor: OperatePulse generation
HOT GAS IN (B22) ±
GND (B40) (*1)R±Y ± W±BIG SW: ON
Hot Gas SW: ONBattery positive voltage
If circuit is not as specified, try replacing the air conditioning control assy with a new one. If the circuit is not
as specified, inspect the circuits connected to the other parts.
(b) Connect the connector to air conditioning control assy and inspect wire harness side connector from
the back side, as shown in the table.
Symbols (Terminal No.)ConditionSpecified condition
HI (A4) ± GND (A1)Ignition switch ON
Turn blower dial: OFF
HINo continuity
Continuity
M2 (A5) ± GND (A1)Ignition switch ON
Turn blower dial: OFF
M2No continuity
Continuity
M1 (A6) ± GND (A1)Ignition switch ON
Turn blower dial: OFF
M1No continuity
Continuity
GND (A1) ± Body groundIgnition switch ON
Turn blower dial: OFF
LONo continuity
Continuity

550ZH±01
I32392
3
4
I32393
5
6
I12755
9
12
Ohmmeter
± HEATER & AIR CONDITIONERCOMBUSTION TYPE POWER HEATER SYSTEM
55±19
AVENSIS REPAIR MANUAL (RM1018E)
INSPECTION
1. INSPECT HEATER ASSY
(a) Inspect the water temperature sensor.
(1) Using an ohmmeter, measure the resistance be-
tween the terminals 3 and 4 of heater wire.
Resistance: Refer to the graph
If the resistance is not as specified, replace the heater wire.
(b) Inspect the overheat sensor.
(1) Using an ohmmeter, measure the resistance be-
tween the terminals 5 and 6 of heater wire.
Resistance: Refer to the graph
If the resistance is not as specified, replace the heater wire.
(c) Inspect the glow plug.
(1) Using an ohmmeter, check the continuity by mea-
sure the resistance between terminals 9 and 12 of
heater wire.
Standard resistance: about 0.5
(20
C, reference
value)
If the resistance is over 1
, replace the heater wire.

I32394
1
2
I32395
Wire harness side: 55±20
± HEATER & AIR CONDITIONERCOMBUSTION TYPE POWER HEATER SYSTEM
AVENSIS REPAIR MANUAL (RM1018E)
(d) Inspect the flame sensor.
(1) Using an ohmmeter, measure the resistance be-
tween terminals 1 and 2 of heater wire.
Resistance: Refer to the graph
If the resistance is not as specified, replace the heater wire.
2. INSPECT HETER SWITCH ASSY
(a) Disconnect the connector from the power heater switch
and inspect the connector on the wire harness side, as
shown in the chart.
Tester connectionConditionSpecified condition
2 ± GroundConstantContinuity
4 ± GroundConstantContinuity
3 ± GroundTurn ignition switch ONBattery voltage
3 ± GroundTurn ignition switch OFFNo voltage
1 ± GroundTurn light control switch TAIL or HEADBattery voltage
1 ± GroundTurn light control switch OFFNo voltage

If the circuit is as specified, replace the power heat-
er switch.

If the circuit is not as specified, inspect the circuits
connected to other parts.

I32396
From back side:
± HEATER & AIR CONDITIONERCOMBUSTION TYPE POWER HEATER SYSTEM
55±21
AVENSIS REPAIR MANUAL (RM1018E)
(b) Connect the connector to the power heater switch and in-
spect the connector from the back side, as shown in the
chart.
Tester connectionConditionSpecified condition
6 ± GroundTurn the ignition switch ON and power heater
switch ONBattery voltage
6 ± GroundTurn the ignition switch ON and power heater
switch OFFNo voltage

If the circuit is not as specified, replace the power
heater switch.