Air Conditioning System: Inspection

WARNING: This page is about a different car, the 2004 Toyota Corolla. However, it is still accessible from the selected car via links, so may be relevant.

COOLER THERMISTOR NO. 1
1. Check resistance between terminals 1 and 2 of cooler thermistor No. 1 at each temperature, as shown in the chart.
  Resistance:
Fig 1: Identifying Cooler Thermistor
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Fig 2: Resistance And Temperature Graph
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COOLER AND ACCESSORY ASSY

Inspect blower switch continuity.

BLOWER SWITCH CONTINUITY CHART

Condition/Circuit	Tester connection	Specified condition
OFF	-	No continuity
LO	1 - 8	Continuity
M1	1 - 6 - 8	Continuity
M2	1 - 5 - 8	Continuity
HI	1 - 4 - 8	Continuity

If continuity is not as specified, replace the air conditioner control assy.

Inspect illumination operation.
Connect the positive (+) lead from the battery to terminal 2 and negative (-) lead to terminal 3 then check that the illuminations light up.

If there is bulb not light up, replace the bulb.

Fig 3: Inspecting Blower Switch

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

COOLER SWITCH HOLE COVER

Inspect switch continuity.

Check the continuity between terminals while switch is pressed, as shown in the chart.

CONTINUITY CHART

Tester connection	Specified condition
2 - 5	Continuity

If continuity is not as specified, replace the cooler switch.

Inspect illumination operation.
Connect the positive (+) lead from the battery to terminal 4 and negative (-) lead to terminal 3 then check that the illuminations light up.

If operation is not as specified, replace the cooler switch.
Inspect indicator operation.
1. Connect the positive (+) lead from the battery to terminal 2 and the negative (-) lead to terminal 1.
2. Push the A/C button in and then check that the indicator lights up.
If operation is not as specified, replace the cooler switch.

Fig 4: Identifying Cooler Switch
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Inspect dimming operation
1. Connect the positive (+) lead from the battery to terminal 2 and the negative (-) lead to terminal 1 while press the switch.
2. Connect the positive (+) lead from battery to terminal 4 and then check that the indicator dims.

If operation is not as specified, replace the cooler switch.

BLOWER RESISTOR

Measure resistance between terminals, as shown in the chart below.

RESISTANCE CHART

Tester connection	Specified condition
1 - 2	1.398 - 1.605 Ω
1 - 3	0.465 - 0.535 Ω
1 - 4	3.069 - 3.531 Ω

If resistance is not as specified, replace the blower resistor.

Fig 5: Identifying Blower Resistor

BLOWER W/FAN MOTOR SUB-ASSY
1. Connect the positive (+) lead from the battery to terminal 2 and negative (-) to terminal 1, then check that the motor operation smoothly.
If operation is not as specified, replace the blower motor.

Fig 6: Identifying Blower W/Fan Motor Sub-Assy
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HEATER BLOWER MOTOR RELAY ASSY

Fig 7: Identifying Heater Blower Motor Relay Assy
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If continuity is not as specified, replace the heater blower motor relay.

Fig 8: Continuity Table
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MAGNET-CLUTCH RELAY

MAGNET-CLUTCH RELAY REFERENCE CHART

Condition	tester connection	Specified condition
constant	1 - 2	Continuity
Apply B+ between terminals 1 and 2.	3 - 5	Continuity

If continuity is not as specified, replace the magnet-clutch relay.

Fig 9: Identifying Magnet-Clutch Relay