Inspection Procedure

1. Remove the A/C fuse from the main body ECU.
2. Measure the resistance according to the value(s) in the table below.

   Standard resistance 

   RESISTANCE SPECIFICATION
   
   

   Tester Connection	Condition	Specified condition
   A/C fuse	Always	Below 1 Ω

3. Reinstall the A/C fuse. NG
   Fig 1: Identifying A/C Fuse

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE FUSE  (See PARTS LOCATION  )

OK: Go to next step 

1. Remove the No. 1 heater control (See DISASSEMBLY  ).
2. Measure the resistance.
   1. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION
      
      

      Tester Connection	Switch Condition	Specified Condition
      2 (L) - 4 (E)	A/C Switch: off	10 kΩ or higher
      2 (L) - 4 (E)	A/C Switch: on	Below 1 Ω.

3. Check that the indicator light comes on.

   OK 

   TESTER CONNECTION AND SPECIFIED CONDITION
   
   

   Tester Connection	Switch Condition	Specified Condition
   Positive battery - 2 (L) Negative battery - 3 (E)	A/C Switch: Off	Indicator light off
   	A/C Switch: On	Indicator light comes on

4. Reinstall the No. 1 heater control.
   Fig 2: Identifying Heater Control Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE NO. 1 HEATER CONTROL  (See DISASSEMBLY  )

OK: Go to next step 

1. Disconnect the G5 No. 1 heater control connector.
2. Measure the voltage according to the value(s) in the table below.

   Standard voltage 

   VOLTAGE SPECIFICATION
   
   

   Tester Connection	Switch Condition	Specified Condition
   G5-2 (L) - Body ground	Ignition switch OFF	Below 1 V
   G5-2 (L) - Body ground	Ignition switch ON	11 to 14 V

3. Reconnect the No. 1 heater control connector.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

Fig 3: Identifying Heater Control Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK: Go to next step 

1. Disconnect the G5 No. 1 heater control connector.
2. Disconnect the G8 air conditioning amplifier connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard resistance 

   RESISTANCE SPECIFICATION
   
   

   Tester Connection	Condition	Specified Condition
   G5-3 (E) - G7-16 (LED)	Always	Below 1 Ω
   G5-4 (B) - G7-15 (A/C)	Always	Below 1 Ω
   G5-3 (E) - Body ground	Always	10 kΩ or higher
   G5-4 (B) - Body ground	Always	10 kΩ or higher

4. Reconnect the No. 1 heater control connector.
5. Reconnect the air conditioning amplifier connector.

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

Fig 4: Identifying Heater Control And Air Conditioning Amplifier Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

OK : PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE  (See PROBLEM SYMPTOMS TABLE  )