Inspection Procedure

1. Disconnect the air conditioning control assembly connector.
   Fig 1: Identifying E23 Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the resistance of the wire harness side connector.

   Standard resistance 

   RESISTANCE SPECIFICATION
   
   

   Tester Connection	Specified Condition
   E23-7 (GND) - Body ground	Below 1 Ω

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

OK: Go to next step 

1. Disconnect the E23 air conditioning control assembly connector.
   Fig 2: Identifying E23 Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the voltage of the wire harness side connector.

   Standard voltage 

   VOLTAGE SPECIFICATION
   
   

   Tester Connection	Condition	Specified Condition
   E23-7 (GND) - E23-2 (IG+)	Ignition switch ON	10 to 14 V

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

OK: Go to next step 

1. Disconnect the E23 control connector.
2. Disconnect the E37 amplifier connector.
   Fig 3: Identifying E23 And E37 Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Measure the resistance of the wire harness side connectors.

   Standard resistance 

   RESISTANCE SPECIFICATION
   
   

   Tester Connection	Specified Condition
   E37-37 (LIN1) - E23-11 (LIN1)	Below 1 Ω

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

OK: Go to next step 

1. Replace the air conditioning control with a new or properly functioning one.
2. Operate the air conditioning control to check that it functions properly.

   Result 

   RESULT REFERENCE
   
   

   Result	Proceed to
   Air conditioning control malfunctions	A
   Air conditioning control functions properly	B

B: END (AIR CONDITIONING CONTROL ASSEMBLY IS FAULTY) 

A: REPLACE AIR CONDITIONING AMPLIFIER