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Inspection Procedure

WARNING: This page is about a different car, the 2002 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.
  1. Check voltage between terminal MGC of A/C control assembly connector and body ground. 
    1. PREPARATION: 
      1. Remove A/C control assembly with connectors still connected. For Camry see AIR CONDITIONER CONTROL ASSEMBLY . For Camry Solara, see AIR CONDITIONING CONTROL ASSEMBLY (AUTO A/C) . If vehicle is equipped with Manual A/C, for Camry Solara, see AIR CONDITIONING CONTROL ASSEMBLY (MANUAL A/C) .
      2. Start the engine and push AUTO switch.
    1. CHECK: 
    2. Check voltage between terminal MGC of A/C control assembly connector and body ground when magnetic clutch is ON and OFF by A/C switch.
      Fig 1: Checking Voltage Between Terminal MGC & Body Ground
      G01051402Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: 

    Fig 2: Determining Voltage Based On A/C Switch Position
    G01051401Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: Go to step   5 
    2. OK: Go to next step. 
  2. Check magnetic clutch relay. 
    1. PREPARATION: 
    2. Remove magnetic clutch relay from cooling unit see AIR CONDITIONING .

    CHECK: 

    1. Check continuity between each pair of terminals shown below of magnetic clutch relay.

    OK: 

    Fig 3: Checking Terminal Continuity Of Magnetic Clutch Relay
    G01051403Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. PREPARATION: 
    2. Apply battery positive (+) voltage between terminals 1 and 4.
    1. CHECK: 
    2. Check continuity between terminals 1 and 9.
      Fig 4: Identifying Terminals For Continuity Check
      G01051404Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. OK: Continuity exists. 
    1. NG: Replace magnetic clutch relay. 
    2. OK: Go to next step. 
  3. Check A/C magnetic clutch. 
    1. PREPARATION: 
    2. Disconnect magnetic clutch connector.
      Fig 5: Locating Magnetic Clutch Connector
      G01051405Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. CHECK: 
    2. Connect positive (+) lead connected to battery to magnetic clutch connector and negative (-) lead connected to battery to body ground.
    1. OK: 
    2. Magnetic clutch is energized. 
    1. NG: Repair A/C magnetic clutch. 
    2. OK: Go to next step. 
  4. Check harness and connector between magnetic clutch relay and A/C compressor, A/C compressor and body ground, see  INTRODUCTION  . 
    1. NG: Repair or replace harness or connector. 
    2. OK: Proceed to next circuit inspection shown on problem symptoms table see  PROBLEM SYMPTOMS TABLE  . 
  5. Check voltage between terminal AC1 of A/C control assembly connector side and body ground. 
    1. PREPARATION: 
      1. Disconnect A/C control connector.
      2. Ignition switch to ON.
    1. CHECK: 
    2. Check voltage between terminal AC1 of A/C control assembly harness side connector.
      Fig 6: Checking Voltage Between Terminal AC1 & Body Ground
      G01051406Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. OK: 
    2. Voltage : 10 - 14 V 
    1. NG: Check and replace ECM. 
    2. OK: Go to next step. 
  6. Check voltage between terminal AC1 of A/C control assembly connector and body ground. 
    1. PREPARATION: 
      1. Remove A/C control assembly with connector still connected, see AIR CONDITIONING .
      2. Start the engine and push AUTO switch.
    1. CHECK: 
    2. Check the voltage between terminal AC1 of A/C control assembly connector and body ground when magnetic clutch is ON and OFF by A/C switch.
      Fig 7: Checking Voltage Between Terminal AC1 & Body Ground
      G01051408Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: 

    Fig 8: Determining Voltage When Magnetic Clutch Is On/Off
    G01051407Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: Check and replace A/C control assembly. 
    2. OK: Go to next step. 
  7. Check voltage between terminal ACT of A/C control assembly and body ground. 
    1. PREPARATION: 
      1. Remove A/C control assembly with connectors still connected, see AIR CONDITIONING .
      2. Start the engine and push AUTO switch.
    1. CHECK: 
    2. Check the voltage between terminal ACT of A/C control assembly and body ground.
      Fig 9: Checking Voltage Between ACT Terminal & Ground Body
      G01051410Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: 

    Fig 10: Determining Voltage Based On A/C Switch In On/Off Position
    G01051409Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: Check and replace ECM. 
    2. OK: Go to next step. 
  8. Check voltage between terminal ACT of ECM connector and body ground, see  ENGINE DIAGNOSTIC  . 
    1. NG: Check and replace ECM. 
    2. OK: Go to next step. 
  9. Check harness and connector between A/C control assembly and ECM, see  INTRODUCTION  . 
    1. NG: Repair or replace harness or connector. 
    2. OK: Proceed to next circuit inspection shown on problem symptoms table, see  PROBLEM SYMPTOMS TABLE  . 
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