Inspection Procedure

1. Check and adjust compressor drive belt tension (see INSPECTION ).
2. Check if the cooler compressor does not lock when starting the engine and turning the A/C switch on.

   OK: Cooler compressor assy does not lock during operations 

If the compressor drive belt slips when A/C switch is turned on, the magnet clutch seems to be locked. If the condition continues for more than 3 seconds, the A/C amplifier turns off the magnet clutch for compressor drive belt protection.

1. NG: REPLACE COOLER COMPRESSOR ASSY 
2. OK: Go to Next Step. 

1. Remove the ECM with the connectors still connected.
2. Start the engine and push the AUTO switch.
3. Measure the waveform according to the condition(s) in WAVEFORM MEASURING CONDITION  .

   OK: 

   WAVEFORM MEASURING CONDITION
   
   

   Tester connection	Condition	Specified condition
   E6-23 (LCK1) - Body ground	Ignition switch ON AUTO switch ON	Waveform operate as shown in Fig 2

   Fig 1: Identifying ECM LCK1 Terminal

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Result: 

Fig 2: Waveform Graph

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. B: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE (SEE  TERMINALS OF ECU  ) 
2. C: Go to step   5 
3. A: Go to Next Step. 

1. Disconnect the A/C lock sensor (cooler compressor assy) connector.
2. Measure the resistance according to the value(s) in A/C LOCK SENSOR (COOLER COMPRESSOR ASSY) RESISTANCE  .

   Standard: 

   A/C LOCK SENSOR (COOLER COMPRESSOR ASSY) RESISTANCE
   
   

   Tester connection	Condition	Specified condition
   1 - 2	at 20°C (68°F)	165 to 205 Ω

   Fig 3: Identifying Terminals Of A/C Lock Sensor Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. NG: REPLACE A/C LOCK SENSOR (COOLER COMPRESSOR ASSY) 
2. OK: Go to Next Step. 

1. Measure the resistance according to the value(s) in A/C LOCK SENSOR (COOLER COMPRESSOR ASSY) - ECM) RESISTANCE  .

   Standard: 

   A/C LOCK SENSOR (COOLER COMPRESSOR ASSY) - ECM) RESISTANCE
   
   

   Tester connection	Condition	Specified condition
   A2-1 - E6-23 (LCK1)	Always	Below 1 Ω
   A2-2 - Body ground	Always	Below 1 Ω
   A2-1 - Body ground	Always	10 kΩ or higher
   E6-23 (LCK1) - Body ground	Always	10 kΩ or higher

   Fig 4: Identifying Terminals Of A/C Lock Sensor Connector

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   Fig 5: Identifying ECM Connector Wire Harness View

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
2. OK: Go to Next Step. 

1. Measure the resistance according to the value(s) in ECM - AIR CONDITIONING AMPLIFIER RESISTANCE  .

   Standard: 

   ECM - AIR CONDITIONING AMPLIFIER RESISTANCE
   
   

   Tester connection	Condition	Specified condition
   E5-33 - (ACLD) - A11-38 (A/CI)	Always	Below 1 Ω
   E5-33 (ACLD) - Body ground	Always	10 kΩ or higher

   Fig 6: Checking Harness & Connector (ECM - Air Conditioning Amplifier)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 
2. OK: REPLACE AIR CONDITIONING AMPLIFIER (SEE  OVERHAUL  )