LEMON Manuals: Even more car manuals for everyone
Home >> Ford >> 2009 >> Taurus X SEL, FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 1349 (HVAC Climate Control System - General Information & Diagnostics) >> Diagnostic Tests >> Climate Control System >> Pinpoint Tests >> Pinpoint Test J: The Air Conditioning (A/C) is Always On >> Pinpoint Test J: The Air Conditioning (A/C) Is Always On

Pinpoint Test J: The Air Conditioning (A/C) Is Always On

WARNING: This page is about a different car, the 2009 Mercury Grand Marquis and 2009 Ford Crown Victoria. However, it is still accessible from the selected car via links, so may be relevant.
  1. J1 CHECK THE AIR CONDITIONING CYCLING SWITCH (ACCS) PCM PID WITH THE A/C OFF 
    • Enter the following diagnostic mode on the diagnostic tool: ACCS PCM PID
    • Place the function selector switch in the OFF position or press the OFF manual override button on the HVAC module.
    • Does the ACCS PCM PID read OFF? 
    1. YES  : Go to  J2.
    2. NO  : Go to  J4.
  2. J2 CHECK FOR VOLTAGE TO THE A/C COMPRESSOR CLUTCH FIELD COIL 
    • Key in OFF position.
    • Disconnect: A/C Compressor Clutch Field Coil C100
    • Key in ON position.
      • Fig 1: Measuring Voltage
      G04002936Courtesy of FORD MOTOR CO.
    • Measure the voltage between A/C compressor clutch field coil C100-1, circuit 321 (GY/WH), harness side and ground.
    • Is any voltage present? 
    1. YES  : Go to  J3.
    2. NO  : ADJUST the A/C compressor clutch gap. REFER to Air Conditioning (A/C) Clutch Air Gap Adjustment . TEST the system for normal operation.
  3. J3 CHECK CIRCUIT 321 (GY/WH) FOR A SHORT TO VOLTAGE 
    • Key in OFF position.
    • Disconnect: A/C Clutch Relay
    • Key in ON position.
      • Fig 2: Measuring Voltage
      G04002936Courtesy of FORD MOTOR CO.
    • Measure the voltage between A/C compressor clutch field coil C100-1, circuit 321 (GY/WH), harness side and ground.
    • Is any voltage present? 
    1. YES  : REPAIR circuit 321 (GY/WH) for a short to voltage. TEST the system for normal operation.
    2. NO  : INSTALL a new A/C clutch relay. CHECK the A/C clutch diode. INSTALL a new diode, if necessary. TEST the system for normal operation.
  4. J4 CHECK CIRCUIT 348 (RD/VT) FOR VOLTAGE 
    • Key in OFF position.
    • Disconnect: A/C Cycling Switch C1081
    • Key in ON position.
      • Fig 3: Checking Circuit For Voltage
      GF0014325Courtesy of FORD MOTOR CO.
    • Measure the voltage between A/C cycling switch C1081-4, circuit 348 (RD/VT), harness side and ground.
    • Is any voltage present? 
    1. YES  : Go to  J5.
    2. NO  : Go to  J6.
  5. J5 CHECK CIRCUIT 348 (RD/VT) FOR A SHORT TO VOLTAGE 
    • Key in OFF position.
    • Disconnect: HVAC Module C228b
    • Key in ON position.
      • Fig 4: Checking Circuit For Voltage
      GF0014325Courtesy of FORD MOTOR CO.
    • Measure the voltage between A/C cycling switch C1081-4, circuit 348 (RD/VT), harness side and ground.
    • Is any voltage present? 
    1. YES  : REPAIR circuit 348 (RD/VT) for a short to voltage. TEST the system for normal operation.
    2. NO  : INSTALL a new function selector switch or HVAC module. REFER to CLIMATE CONTROL article. TEST the system for normal operation.
  6. J6 CHECK CIRCUIT 883 (PK/LB) FOR A SHORT TO VOLTAGE 
    • Key in OFF position.
    • Disconnect: PCM C175b
    • Key in ON position.
      • Fig 5: Measuring Voltage
      GF0004335Courtesy of FORD MOTOR CO.
    • Measure the voltage between A/C cycling switch C1081-1, circuit 883 (PK/LB), harness side and ground.
    • Is any voltage present? 
    1. YES  : REPAIR circuit 883 (PK/LB) for a short to voltage. TEST the system for normal operation.
    2. NO  : INSTALL a new PCM. TEST the system for normal operation.
scientia non olet · About LEMON Manuals