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HVAC System-General Information: Diagnosis Ford Focus I рестайлинг

A/c Compressor 44 illustrations ~4067 words

Inspection And Verification

  1. Verify the customer concern.
  2. Visually inspect for obvious signs of mechanical and electrical damage. VISUAL INSPECTION CHART Mechanical Electrical Accessory drive belt Refrigerant lines Condenser Fuse(s) Wiring harness Electrical connector(s)
  3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
  4. If the cause is not visually evident, verify the symptom and refer to the «SYMPTOM CHART»(ref-207782-S24519393222005120100000) .

Symptom Chart

ConditionPossible SourcesAction
The heater blower motor is inoperative/does not operate correctlyFuse(s). Circuit(s). Heater blower motor. Heater blower switch. Heater blower series resistor.Go To PINPOINT TEST A: THE HEATER BLOWER MOTOR IS INOPERATIVE/DOES NOT OPERATE CORRECTLY .
The heater blower motor running continuouslyCircuit(s). Heater blower switch.Go To PINPOINT TEST B: THE HEATER BLOWER MOTOR RUNNING CONTINUOUSLY .
The air conditioning (A/C) is inoperativeFuse(s). Circuit(s). A/C compressor clutch diode. A/C compressor clutch. A/C wide open throttle (WOT) relay. Refrigerant level. Dual pressure switch. A/C compressor cycling switch. Powertrain control module (PCM). Heater control module.Go To PINPOINT TEST C: THE AIR CONDITIONING (A/C) IS INOPERATIVE .
Insufficient air conditioning (A/C) cooling (A/C compressor clutch is working correctly)Engine cooling fan. Refrigerant level. A/C circuit.REFER to WDS for additional engine management diagnostics. CHECK the refrigerant level with the R-134a refrigerant center and REPAIR the system if necessary.

SYMPTOM

PINPOINT TEST A: THE HEATER BLOWER MOTOR IS INOPERATIVE/DOES NOT OPERATE CORRECTLY

A1 CHECK THE HEATER BLOWER MOTOR AT ALL SPEED SETTINGS

  1. Key in ON position.
  2. Operate the heater blower motor in all switch positions.
  3. Is the heater blower motor inoperative on all the speeds settings?

Yes

GO to A2.

No

GO to A8.

A2 CHECK FUSE F64

  1. Key in OFF position.
  2. Check fuse: Fuse F64 (BJB).
  3. Is the fuse OK?

Yes

GO to A3.

No

INSTALL a new fuse F64 (40 A). TEST the system for normal operation. If the fuse blows again, LOCATE and REPAIR the short to ground using SYSTEM WIRING DIAGRAMS . TEST the system for normal operation.

A3 CHECK THE VOLTAGE AT FUSE F64

  1. Connect: Fuse F64 (BJB).
  2. Key in ON position.
  3. Measure the voltage between fuse F64, (40 A), harness side and ground.
  4. Is battery voltage indicated?

Yes

GO to A4.

No

REPAIR the power supply of fuse F64 using the wiring diagrams. TEST the system for normal operation.

A4 CHECK THE VOLTAGE AT HEATER BLOWER MOTOR

Scheme 1

Scheme 1
Scheme 1
  1. Key in OFF position.
  2. Disconnect: Connector C789 of Heater Blower Motor.
  3. Key in ON position.
  4. Measure the voltage between heater blower motor, connector C789, pin 1, circuit 15-FA18 (GN/OG), harness side and ground.
  5. Is battery voltage indicated?

Yes

GO to A5.

No

REPAIR circuit between heater blower motor and fuse F64 using the wiring diagrams. TEST the system for normal operation.

A5 CHECK THE HEATER BLOWER MOTOR GROUND CIRCUIT

Scheme 2

Scheme 2
Scheme 2
  1. Key in OFF position.
  2. Turn the heater blower switch to maximum speed.
  3. Measure the resistance between heater blower motor, connector C789, pin 2, circuit 31S-FA18 (BK/RD), wiring harness side and ground.
  4. Is the resistance less than 2 ohms?

Yes

INSTALL a new heater blower motor. TEST the system for normal operation.

No

GO to A6.

A6 CHECK THE CIRCUIT BETWEEN THE HEATER BLOWER MOTOR AND THE HEATER BLOWER SWITCH FOR OPEN

Scheme 3

Scheme 3
Scheme 3
  1. Disconnect: Connector C469 of Heater Blower Switch.
  2. Measure the resistance between heater blower motor, connector C789, pin 2, circuit 31S-FA18 (BK/RD), harness side and heater blower switch, connector C469, pin 6, circuit 31S-FA33 (BK/OG), harness side.
  3. Is the resistance less than 2 ohms?

Yes

GO to A7.

No

REPAIR circuit 31S-FA18 (BK/RD) between heater blower motor and splice S24 using the wiring diagrams.

TEST the system for normal operation.

A7 CHECK THE HEATER BLOWER SWITCH GROUND CIRCUIT

Scheme 4

Scheme 4
Scheme 4
  1. Measure the resistance between heater blower switch, connector C469, pin 2, circuit 31-FA25 (BK), harness side and ground.
  2. Is the resistance less than 2 ohms?

Yes

INSTALL a new heater blower switch. TEST the system for normal operation.

No

REPAIR circuit between heater blower switch and ground connection G14 using the wiring diagrams. TEST the system for normal operation.

A8 CHECK THE HEATER BLOWER MOTOR AT MAXIMUM SPEED

  1. Turn the heater blower switch to maximum speed.
  2. Does the heater blower motor operate correctly?

Yes

GO to A10.

No

GO to A9.

A9 CHECK THE CIRCUIT BETWEEN THE HEATER BLOWER MOTOR AND THE HEATER BLOWER SWITCH FOR OPEN

Scheme 5

Scheme 5
Scheme 5
  1. Key in OFF position.
  2. Disconnect: Connector C469 of Heater Blower Switch.
  3. Disconnect: Connector C789 of Heater Blower Motor.
  4. Measure the resistance between heater blower motor, connector C789, pin 2, circuit 31S-FA18 (BK/RD), harness side and heater blower switch, connector C469, pin 6, circuit 31S-FA33 (BK/OG), harness side.
  5. Is the resistance less than 2 ohms?

Yes

INSTALL a new heater blower switch. TEST the system for normal operation.

No

REPAIR circuit 31S-FA33 (BK/OG) between splice S24 and heater blower switch using the wiring diagrams. TEST the system for normal operation.

A10 CHECK THE HEATER BLOWER SWITCH

Scheme 6

Scheme 6
Scheme 6
  1. Key in OFF position.
  2. Disconnect: Connector C469 of Heater Blower Switch.
  3. Key in ON position.
  4. Measure the voltage between heater blower switch, connector C469, pin 5, circuit 31S-FA32 (BK/BU), harness side and ground.
  5. Measure the voltage between heater blower switch, connector C469, pin 3, circuit 31S-FA31 (BK/YE), harness side and ground.
  6. Measure the voltage between heater blower switch, connector C469, pin 1, circuit 31S-FA30 (BK/WH), harness side and ground.
  7. Is battery voltage indicated in all measurements?

Yes

INSTALL a new heater blower switch. TEST the system for normal operation.

No

GO to A11.

A11 CHECK THE VOLTAGE AT THE HEATER BLOWER SERIES RESISTOR

Scheme 7

Scheme 7
Scheme 7
  1. Key in OFF position.
  2. Disconnect: Connector C470 of Heater Blower Series Resistor.
  3. Key in ON position.
  4. Measure the voltage between heater blower series resistor, connector C470, pin 1, circuit 31S-FA33 (BK/OG), harness side and ground.
  5. Is battery voltage indicated?

Yes

GO to A12.

No

REPAIR circuit between splice S24 and heater blower series resistor using the wiring diagrams. TEST the system for normal operation.

A12 CHECK THE CIRCUIT BETWEEN THE HEATER BLOWER SERIES RESISTOR AND THE HEATER BLOWER SWITCH FOR OPEN - HIGH SPEED

Scheme 8

Scheme 8
Scheme 8
  1. Key in OFF position.
  2. Measure the resistance between heater blower series resistor, connector C470, pin 4, circuit 31S-FA32 (BK/BU), harness side and heater blower switch, connector C469, pin 5, circuit 31S-FA32 (BK/BU), harness side.
  3. Is the resistance less than 2 ohms?

Yes

GO to A13.

No

REPAIR circuit 31S-FA32 (BK/BU) between heater blower series resistor and the heater blower switch using the wiring diagrams. TEST the system for normal operation.

A13 CHECK THE CIRCUIT BETWEEN THE HEATER BLOWER SERIES RESISTOR AND THE HEATER BLOWER SWITCH FOR OPEN - MEDIUM SPEED

Scheme 9

Scheme 9
Scheme 9
  1. Measure the resistance between heater blower series resistor, connector C470, pin 2, circuit 31S-FA31 (BK/YE), harness side and heater blower switch, connector C469, pin 3, circuit 31S-FA31 (BK/YE), harness side.
  2. Is the resistance less than 2 ohms?

Yes

GO to A14.

No

REPAIR circuit 31S-FA31 (BK/YE) between heater blower series resistor and heater blower switch using the wiring diagrams. TEST the system for normal operation.

A14 CHECK THE CIRCUIT BETWEEN THE HEATER BLOWER SERIES RESISTOR AND THE HEATER BLOWER SWITCH FOR OPEN - LOW SPEED

Scheme 10

Scheme 10
Scheme 10
  1. Measure the resistance between heater blower series resistor, connector C470, pin 3, circuit 31S-FA30 (BK/WH), harness side and heater blower switch, connector C469, pin 1, circuit 31S-FA30 (BK/WH), harness side.
  2. Is the resistance less than 2 ohms?

Yes

INSTALL a new heater blower series resistor. TEST the system for normal operation.

No

REPAIR circuit 31S-FA30 (BK/WH) between heater blower series resistor and heater blower switch using the wiring diagrams. TEST the system for normal operation.

PINPOINT TEST B: THE HEATER BLOWER MOTOR RUNNING CONTINUOUSLY

B1 CHECK THE HEATER BLOWER SWITCH

  1. Key in OFF position.
  2. Disconnect: Connector C469 of Heater Blower Switch.
  3. Key in ON position.
  4. Is the heater blower motor running continuously?

Yes

GO to B2.

No

INSTALL a new heater blower switch. TEST the system for normal operation.

B2 CHECK THE CIRCUITS AT THE HEATER BLOWER SERIES RESISTOR FOR SHORT TO GROUND

  1. Key in OFF position.
  2. Disconnect: Connector C470 of Heater Blower Series Resistor.
  3. Key in ON position.
  4. Is the heater blower motor running continuously?

Yes

CHECK all circuits connected to splice S24 for a short to ground using the wiring diagrams and REPAIR any short circuit(s) found. TEST the system for normal operation.

No

CHECK all circuits between heater blower series resistor and heater blower switch for short to ground using the wiring diagrams and REPAIR any short circuit(s) found. TEST the system for normal operation.

PINPOINT TEST C: THE AIR CONDITIONING (A/C) IS INOPERATIVE

C1 CHECK THE SYSTEM USING THE WDS

  1. Key in OFF position.
  2. Connect the diagnostic tool.
  3. Check the powertrain control module (PCM) using the WDS.
  4. Are any diagnostic trouble codes (DTCs) indicated?

Yes

WORK through the DTCs, according to the WDS instructions.

CLEAR the error memory and TEST the system for normal operation.

No

Vehicles built 08-2001 onward: GO to C2. Vehicles built up to 08/2001: GO to C4.

C2 CHECK FUSE F15

  1. Key in OFF position.
  2. Check fuse: Fuse F15 (BJB).
  3. Is the fuse OK?

Yes

GO to C3.

No

INSTALL a new fuse F15 (10 A). TEST the system for normal operation. If the fuse blows again, CHECK the A/C compressor clutch diode and if necessary INSTALL a new diode. If the diode is OK, LOCATE and REPAIR the short to ground using the wiring diagrams. TEST the system for normal operation.

C3 CHECK THE VOLTAGE AT FUSE F15

  1. Connect: Fuse F15 (BJB).
  2. Measure the voltage between fuse F15 (10 A), harness side and ground.
  3. Is battery voltage indicated?

Yes

GO to C4.

No

REPAIR the power supply of fuse F15 using the wiring diagrams. TEST the system for normal operation.

C4 CHECK FUSE F36

  1. Check fuse: Fuse F36 (CJB).
  2. Is the fuse OK?

Yes

GO to C5.

No

INSTALL a new fuse F36 (7.5 A). TEST the system for normal operation. If the fuse blows again, LOCATE and REPAIR the short to ground using the wiring diagrams. TEST the system for normal operation.

C5 CHECK THE VOLTAGE AT FUSE F36

  1. Connect: Fuse F36 (CJB).
  2. Measure the voltage between fuse F36 (7.5 A), harness side and ground.
  3. Is battery voltage indicated?

Yes

Vehicles built 08/2001 onward: GO to C6. Vehicles built up to 08/2001: GO to C8.

No

REPAIR the power supply of fuse F36 using the wiring diagrams. TEST the system for normal operation.

C6 CHECK FUSE F45

  1. Check fuse: Fuse F45 (CJB).
  2. Is the fuse OK?

Yes

Go to C7.

No

INSTALL a new fuse F45 (7.5 A). TEST the system for normal operation. If the fuse blows again, LOCATE and REPAIR the short to ground using the wiring diagrams. TEST the system for normal operation.

C7 CHECK THE VOLTAGE AT FUSE F45

  1. Connect: Fuse F45 (CJB).
  2. Key in ON position.
  3. Measure the voltage between fuse F45 (7.5 A), harness side and ground.
  4. Is battery voltage indicated?

Yes

GO to C8.

No

REPAIR the power supply of fuse F45 using the wiring diagrams. TEST the system for normal operation.

C8 CHECK FUSE F58

  1. Check fuse: Fuse F58 (CJB).
  2. If the fuse OK?

Yes

GO to C9.

No

INSTALL a new fuse F58 (7.5 A). TEST the system for normal operation. If the fuse blows again, LOCATE and REPAIR the short to ground using the wiring diagrams. TEST the system for normal operation.

C9 CHECK THE VOLTAGE AT FUSE F58

  1. Connect: Fuse F58 (CJB).
  2. Key in ON position.
  3. Measure the voltage between fuse F58 (7.5 A), harness side and ground.
  4. Is battery voltage indicated?

Yes

GO to C10.

No

REPAIR the power supply of fuse F58 using the wiring diagrams. TEST the system for normal operation.

C10 CHECK THE VOLTAGE AT THE A/C WIDE OPEN THROTTLE (WOT) RELAY

Scheme 11

Scheme 11
Scheme 11
  1. Key in OFF position.
  2. Disconnect: A/C WOT relay of socket C1011 (BJB).
  3. Measure the voltage between A/C WOT relay, socket C1011, pin 3, circuit 30-FA12 (RD/BU), harness side and ground.
  4. Is battery voltage indicated?

Yes

GO to C11.

No

REPAIR circuit 30-FA12 (RD/BU) between fuse F15 and A/C WOT relay using the wiring diagrams. TEST the system for normal operation.

C11 CHECK THE CONTROL VOLTAGE AT THE A/C WOT RELAY

Scheme 12

Scheme 12
Scheme 12
  1. Key in START position.
  2. Measure the voltage between A/C WOT relay, socket C1011, pin 1, circuit 15-FA11 (GN/YE), harness side and ground.
  3. Is battery voltage indicated?

Yes

GO to C12.

No

REPAIR circuit 15-FA11 (GN/YE) between splice S117 and A/C WOT relay using the wiring diagrams. TEST the system for normal operation.

C12 CHECK THE A/C COMPRESSOR CLUTCH CIRCUIT

Scheme 13

Scheme 13
Scheme 13
  1. Key in OFF position.
  2. Connect a fused jumper wire (10 A) at the A/C WOT relay, socket C1011, between pin 3 and pin 5, harness side.
  3. Check the operation of the A/C compressor clutch.
  4. Does the A/C compressor clutch operate?

Yes

GO to C15.

No

GO to C13.

C13 CHECK THE CIRCUIT BETWEEN THE A/C WOT RELAY AND THE A/C COMPRESSOR CLUTCH FOR OPEN

Scheme 14

Scheme 14
Scheme 14
  1. Disconnect: Connector C957 of A/C Compressor Clutch.
  2. Measure the resistance between A/C WOT relay, socket C1011, pin 5, harness side and A/C compressor clutch, connector C957, pin 1, circuit 15S-FA6 (GN/YE), harness side.
  3. Is the resistance less than 2 ohms?

Yes

GO to C14.

No

REPAIR circuit between A/C WOT relay and A/C compressor clutch using the wiring diagrams. TEST the system for normal operation.

C14 CHECK THE A/C COMPRESSOR CLUTCH GROUND CIRCUIT

Scheme 15

Scheme 15
Scheme 15
  1. Measure the resistance between A/C compressor clutch, connector C957, pin 2, circuit 31-FA6 (BK), harness side and ground.
  2. Is the resistance less than 2 ohms?

Yes

INSTALL a new A/C compressor clutch. TEST the system for normal operation.

No

REPAIR circuit between A/C compressor clutch and ground connection G56 using the wiring diagrams. TEST the system for normal operation.

C15 CHECK THE A/C WOT RELAY GROUND CIRCUIT

  1. Key in ON position.
  2. Turn on the heater blower motor.
  3. Turn on the air conditioning.
  4. With the engine running, check the voltage at the A/C WOT relay, socket C1011, between pin 1 and pin 2 using a test lamp(12V, 1.2W).
  5. Does the test lamp illuminate?

Yes

INSTALL a new A/C WOT relay. TEST the system for normal operation.

No

GO to C16.

C16 CHECK THE REFRIGERANT LEVEL

  1. Key in OFF position.
  2. Check the refrigerant level in the system.
  3. Is the refrigerant level in the system identical with the manufacturer's specifications?

Yes

GO to C17.

No

FILL the system with the correct amount of refrigerant. CHECK the system for leaks and TEST the system for normal operation.

C17 CHECK THE CIRCUIT BETWEEN HEATER CONTROL MODULE AND PCM FOR SHORT TO VOLTAGE

Scheme 16

Scheme 16
Scheme 16
  1. Disconnect: Connector C380 of Heater Control Module.
  2. Disconnect: Connector C415 of PCM.
  3. Key in ON position.
  4. Measure the voltage between heater control module, connector C380, pin 9, circuit 15S-FA38 (GN/RD), harness side and ground.
  5. Is a voltage indicated?

Yes

REPAIR circuit between heater control module and PCM using the wiring diagrams. TEST the system for normal operation.

No

GO to C18.

C18 CHECK THE CIRCUIT BETWEEN HEATER CONTROL MODULE AND PCM FOR SHORT TO GROUND

Scheme 17

Scheme 17
Scheme 17
  1. Key in OFF position.
  2. Measure the resistance between heater control module, connector C380, pin 9, circuit 15S-FA38 (GN/RD), harness side and ground.
  3. Is the resistance greater than 10,000 ohms?

Yes

GO to C19.

No

REPAIR circuit between heater control module and PCM using the wiring diagrams. TEST the system for normal operation.

C19 CHECK THE VOLTAGE AT THE DUAL PRESSURE SWITCH

Scheme 18

Scheme 18
Scheme 18
  1. Connect: Connector C380 of Heater Control Module.
  2. Connect: Connector C415 of PCM.
  3. Disconnect: Connector C882 of Dual Pressure Switch.
  4. Key in START position.
  5. Turn on the heater blower motor.
  6. Turn on the air conditioning.
  7. Measure the voltage between dual pressure switch, connector C882, pin 1, circuit 15S-FA38 (GN/RD), harness side and ground.
  8. Is battery voltage indicated?

Yes

GO to C20.

No

GO to C27.

C20 CHECK THE DUAL PRESSURE SWITCH

Scheme 19

Scheme 19
Scheme 19
  1. Key in OFF position.
  2. Measure the resistance at dual pressure switch, connector C882, between pin 1 and pin 4, component side.
  3. Is the resistance less than 2 ohms?

Yes

GO to C21.

No

INSTALL a new dual pressure switch. TEST the system for normal operation.

C21 CHECK THE VOLTAGE AT THE A/C COMPRESSOR CYCLING SWITCH

Scheme 20

Scheme 20
Scheme 20
  1. Connect: Connector C882 of Dual Pressure Switch.
  2. Disconnect: Connector C692 of A/C Compressor Cycling Switch.
  3. Key in START position.
  4. Turn on the heater blower motor.
  5. Turn on the air conditioning.
  6. Measure the voltage between A/C compressor cycling switch, connector C692, pin 1, circuit 15S-FA17 (GN/OG), harness side and ground.
  7. Is battery voltage indicated?

Yes

GO to C22.

No

REPAIR circuit 15S-FA17 (GN/OG) between dual pressure switch and A/C compressor cycling switch using the wiring diagrams. TEST the system for normal operation.

C22 CHECK THE A/C COMPRESSOR CYCLING SWITCH

Scheme 21

Scheme 21
Scheme 21
  1. Key in OFF position.
  2. Measure the resistance between the A/C cycling switch terminals.
  3. Is the resistance less than 21 ohms?

Yes

INSTALL a new A/C compressor cycling switch. TEST the system for normal operation.

No

GO to C23.

C23 CHECK THE CIRCUIT BETWEEN THE A/C COMPRESSOR CYCLING SWITCH AND THE PCM FOR OPEN

Scheme 22

Scheme 22
Scheme 22
  1. Disconnect: Connector C415 of PCM.
  2. Measure the resistance between PCM, connector C415, pin 41, circuit 15S-RE8 (GN/YE), harness side and A/C compressor cycling switch, connector C692, pin 4, circuit 15S-RE8 (GN/YE), harness side.
  3. Is the resistance less than 2 ohms?

Yes

GO to C24.

No

REPAIR circuit 15S-RE8 (GN/YE) between A/C compressor cycling switch and PCM using the wiring diagrams. TEST the system for normal operation.

C24 CHECK THE CIRCUIT BETWEEN THE A/C WOT RELAY AND THE PCM FOR SHORT TO VOLTAGE

Scheme 23

Scheme 23
Scheme 23
  1. Key in ON position.
  2. Measure the voltage between PCM, connector C415, pin 69, circuit 31S-FA11 (BK/YE), harness side and ground.
  3. Is a voltage indicated?

Yes

REPAIR circuit 31S-FA11 (BK/YE) between A/C WOT relay and PCM using the wiring diagrams. TEST the system for normal operation.

No

GO to C25.

C25 CHECK THE CIRCUIT BETWEEN THE A/C WOT RELAY AND THE PCM FOR SHORT TO GROUND

Scheme 24

Scheme 24
Scheme 24
  1. Key in OFF position.
  2. Measure the resistance between PCM, connector C415, pin 69, circuit 31S-FA11 (BK/YE), harness side and ground.
  3. Is the resistance greater than 10,000 ohms?

Yes

GO to C26.

No

REPAIR circuit 31S-FA11 (BK/YE) between A/C WOT relay and PCM using the wiring diagrams. TEST the system for normal operation.

C26 CHECK THE CIRCUIT BETWEEN THE A/C WOT RELAY AND THE PCM FOR OPEN

Scheme 25

Scheme 25
Scheme 25
  1. Measure the resistance between PCM, connector C415, pin 69, circuit 31S-FA11 (BK/YE), harness side and A/C WOT relay, socket C1011, pin 2, harness side.
  2. Is the resistance less than 2 ohms?

Yes

CHECK and if necessary INSTALL a new PCM. TEST the system for normal operation.

No

REPAIR circuit between A/C WOT relay and PCM using the wiring diagrams. TEST the system for normal operation.

C27 CHECK THE CIRCUIT BETWEEN DUAL PRESSURE SWITCH AND HEATER CONTROL MODULE FOR OPEN

Scheme 26

Scheme 26
Scheme 26
  1. Key in OFF position.
  2. Disconnect: Connector C380 of Heater Control Module.
  3. Measure the resistance between dual pressure switch, connector C882, pin 1, circuit 15S-FA38 (GN/RD), harness side and heater control module, connector C380, pin 9, circuit 15S-FA38 (GN/RD), harness side.
  4. Is the resistance less than 2 ohms?

Yes

GO to C28.

No

REPAIR circuit 15S-FA38 (GN/RD) between dual pressure switch and heater control module using the wiring diagrams. TEST the system for normal operation.

C28 CHECK THE HEATER CONTROL MODULE GROUND CIRCUIT

Scheme 27

Scheme 27
Scheme 27
  1. Measure the resistance between heater control module, connector C380, pin 12, circuit 91-FA13 (BK/OG), harness side and ground. Is the resistance less than 2 ohms?

Yes

GO to C29.

No

REPAIR circuit between heater control module and ground connection G41 using the wiring diagrams. TEST the system for normal operation.

C29 CHECK THE VOLTAGE AT THE HEATER CONTROL MODULE

Scheme 28

Scheme 28
Scheme 28
  1. Measure the voltage between heater control module, connector C380, pin 8, circuit 29-FA13 (OG), harness side and ground.
  2. Is battery voltage indicated?

Yes

GO to C30.

No

REPAIR circuit between heater control module and fuse F36 using the wiring diagrams. TEST the system for normal operation.

C30 CHECK THE VOLTAGE AT THE HEATER CONTROL MODULE

Scheme 29

Scheme 29
Scheme 29
  1. Key in ON position.
  2. Measure the voltage between heater control module, connector C380, pin 10, circuit 15-FA13 (GN/RD), harness side and ground.

C31 CHECK THE CONTROL VOLTAGE AT THE HEATER CONTROL MODULE

Scheme 30

Scheme 30
Scheme 30
  1. Turn off the heater blower switch.
  2. Measure the voltage between heater control module, connector C380, pin 6, circuit 31S-FA26 (BK/RD), harness side and ground. Is battery voltage indicated?

Yes

CHECK and if necessary INSTALL a new heater control module. TEST the system for normal operation.

No

REPAIR circuit 31S-FA26 (BK/RD) between heater control module and heater blower switch using the wiring diagrams. TEST the system for normal operation.

Diagnostic Table

Pinpoint Test C

C1 Additional Possible Cause Components Associated With Inadequate Compressor Operation
  1. PRESSURE DIAGNOSTIC TABLE High (Discharge) Pressure Low (Suction) Pressure Component - Causes High or clutch cycling High Condenser - inadequate airflow. High Normal to high Engine - overheating. Normal to high Normal Refrigerant overcharge - air in refrigerant. Normal to low High Fixed orifice tube - missing O-rings leaking/missing. Normal to low Normal to high A/C suction line - partially restricted or plugged (1) . Normal to low Low or clutch cycling Low refrigerant charge, A/C suction line - partially restricted or plugged (2) A/C cycling switch - sticking closed (if equipped). Erratic operation or compressor not running A/C cycling switch - poor connection at A/C clutch connector or clutch cycling switch connector. A/C electrical circuit erratic - see «SYSTEM WIRING DIAGRAMS»(ref-163988) . Normal to low High Compressor - low performance. Additional Possible Cause Components Associated With Inadequate Compressor Operation Compressor drive belt - loose Compressor clutch - slipping Clutch coil open - shorted, or loose mounting Control assembly switch - dirty contacts or sticking open Clutch wiring circuit - high resistance, open or blown fuse Compressor operation interrupted by engine computer Additional Possible Cause Components Associated With a Damaged Compressor Incorrect clutch air-gap Suction accumulator - refrigerant oil bleed hose plugged Refrigerant leaks (1) Low pressure reading will be normal to high if pressure is taken at accumulator and if restriction is downstream of service access valve. (2) Low pressure reading will be low if pressure is taken near the compressor and restriction is upstream of service access valve.

Scheme 31

Scheme 31: Air Conditioning (A/C) Clutch Air Gap Adjustment
Scheme 31: Air Conditioning (A/C) Clutch Air Gap Adjustment

Note. The A/C clutch air gap must be measured and adjusted, using the correct method, to ensure correct A/C function. An A/C clutch air gap that is greater than specifications may reduce A/C compressor performance or cause the A/C compressor to be inoperative, and may cause premature wear of the A/C clutch disc and hub and A/C compressor pulley. An A/C clutch air gap that is less than specifications may cause the A/C compressor to operate continuously, or may cause premature wear of the A/C clutch disc and hub and A/C compressor pulley.

Note. It is not necessary to recover the refrigerant for A/C clutch air gap adjustment if the A/C compressor is not being removed from the vehicle.

Scheme 32

Scheme 32
Scheme 32

Scheme 33

Scheme 33
Scheme 33

Scheme 34

Scheme 34
Scheme 34

Scheme 35

Scheme 35
Scheme 35
  1. Measure the A/C clutch air gap at three equally spaced places between the A/C clutch disc and the A/C compressor pulley. If the clutch air gap is not within specification, proceed with adjustment.
  2. Remove the A/C clutch disc and hub bolt. Hold the A/C clutch disc and hub with the special tool. Remove A/C clutch disc and hub bolt.
  3. Remove the A/C clutch disc and hub. Thread an 8 x 1.25 mm bolt into the A/C clutch disc and hub to force it from the A/C compressor shaft. Lift the A/C clutch disc and hub and the A/C clutch disc and hub spacer from the A/C compressor shaft.
  4. Add or remove A/C clutch disc and hub spacers based on the measurements taken.
  5. Install the A/C clutch disc and hub.
  6. Install the A/C clutch disc and hub bolt. Hold the A/C clutch disc and hub with the special tool. Install the A/C clutch disc and hub bolt.
  7. Measure the A/C clutch air gap at three equally spaced positions between the A/C clutch disc and the A/C compressor pulley. Repeat adjustment procedure if needed.

Scheme 36

Scheme 36: Manifold Gauge Set Connection
Scheme 36: Manifold Gauge Set Connection

Scheme 37

Scheme 37
Scheme 37

Scheme 38

Scheme 38
Scheme 38

Scheme 39

Scheme 39
Scheme 39

Scheme 40

Scheme 40
Scheme 40

Scheme 41

Scheme 41
Scheme 41
  1. Turn both valves on the R-134a Manifold Gauge Set clockwise to close the low-and high-pressure hoses to the center manifold and center hose.
  2. Remove the A/C charging valve cap (19D702) from the low-pressure service gauge port valve.
  3. Remove the A/C charging valve cap from the high-pressure service gauge port valve.
  4. Connect the R-134a Manifold Gauge Set low-pressure hose and the R-134a low side quick disconnect to the low-pressure service gauge port valve.
  5. Connect the R-134a Manifold Gauge Set high-pressure hose and the R-134a high side quick disconnect to the high-pressure service gauge port valve.

Scheme 42

Scheme 42: Electronic Leak Detection
Scheme 42: Electronic Leak Detection
CAUTIONGood ventilation is necessary in the area where electronic A/C leak testing is to be carried out. If the surrounding air is contaminated with refrigerant gas, the leak detector will indicate this gas all the time. Odors from other chemicals such as antifreeze, diesel fuel, disc brake cleaner or other cleaning solvents can cause the same problem. Using a fan to ventilate the area to be tested before proceeding with the leak detection procedure is helpful in removing small traces of contamination from the air, but the fan should be turned off during actual testing.

Scheme 43

Scheme 43
Scheme 43
  1. Leak test the refrigerant system using the Refrigerant Leak Detector. Follow the instructions included with the leak detector for handling and operation techniques.
  2. If a leak is found, recover the refrigerant. For additional information, refer to «AIR CONDITIONING (A/C) SYSTEM RECOVERY, EVACUATION AND CHARGING»(ref-207782-S20604127602005120100000) . Repair the system. Test the system for normal operation.

Scheme 44

Scheme 44: Fluorescent Dye Leak Detection
Scheme 44: Fluorescent Dye Leak Detection

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