Ford Mustang Service Manual: Symptom Chart

Inspection and Verification

1. Verify the customer's concern by operating the climate control system to duplicate the condition.

2. Inspect to determine if one of the following mechanical or electrical concerns apply:

Visual Inspection Chart

Mechanical Electrical
  • Loose, missing or damaged A/C compressor drive belt.
  • Loose or disconnected A/C clutch.
  • Loose, misrouted or damaged vacuum lines. a
  • Broken or leaking refrigerant lines.
  • Broken or leaking vacuum control motor
  • Open fuses.
  • Blower motor inoperative.
  • A/C compressor inoperative.
  • Circuitry open/shorted.
  • Disconnected electrical connectors.

a - A leak in the vacuum control circuit may occur during acceleration (slow leak), at all times (large leak), or only when specific functions are selected (indicating a leak in that portion of the circuit). The vacuum hoses used in the passenger compartment control circuit are constructed from PVC plastic material. The vacuum hoses used in the engine compartment are constructed of Hytrel. Because of the materials used, never pinch the vacuum hoses off during diagnosis to locate a leak. A wood golf tee can be used as a plug when it is necessary to plug one end of a vacuum hose for leak test purposes.

3. If the inspection reveals obvious concerns that can be readily identified, repair as required.

4. If the concern remains after the inspection, connect the scan tool to the data link connector (DLC) located beneath the instrument panel and select the vehicle to be tested from the scan tool menu. If the vehicle selection cannot be entered:

  • check that the program card is correctly installed.
  • check the connections to the vehicle.
  • check the ignition switch position.

If the scan tool still does not allow the vehicle selection to be entered, refer to the scan tool manual.

5. Carry out the DATA LINK DIAGNOSTIC TEST using the scan tool. If the scan tool responds with:

  • CKT 914, CKT 915 or CKT 70 = ALL MODULE NO RESPONSE/NOT EQUIPPED, go to Communication System Diagnostics in Section to diagnose network concern.
  • If the powertrain control module (PCM) is not listed for a communication concern, turn the A/C function selector switch to OFF and execute self-test diagnostics for the PCM.

6. If any PCM DTCs are retrieved, and are related to the concern, go to the Powertrain Control Module Diagnostic Trouble Code (DTC) Index to continue diagnostics.

7. If no DTCs related to the concern are retrieved, go to the Symptom Chart to continue diagnostics.

Powertrain Control Module Diagnostic Trouble Code (DTC) Index

DTC Description Action
P1460 WOT A/C cutout circuit malfunction Refer to the Powertrain Control/Emissions Diagnosis (PC/ED) manual
P1464 A/C demand out of self-test range GO to DTC P1464.
    Inspection and Verification
    Inspection and Verification 1. Verify the customer's concern by operating the climate control system to duplicate the condition. 2. Inspect to determine if one of the following mechanical or elect ...

    Pinpoint Tests
    Inspection and Verification 1. Verify the customer's concern by operating the climate control system to duplicate the condition. 2. Inspect to determine if one of the following mechanical or elect ...

    Other materials:

    Parking, Rear and License Lamps
    Headlamps Refer to Wiring Diagrams Cell 85 , Headlamps for schematic and connector information. Special Tool(s) 73III Automotive Meter or equivalent 105-R0057 Inspection and Verification 1. Verify the customer concern by operating th ...

    Throttle Body
    Fuel Charging and Controls The fuel injection supply manifold: receives fuel from the fuel supply line. delivers fuel to the fuel injector. The throttle body: controls air supply to the intake manifold by positioning the throttle plate. connects the a ...

    Exhaust Manifold RH
    Engine WARNING: Do not operate the engine with the hood open until the fan blade has been first examined for possible cracks and separation. The 4.6L (4V) (281 CID) is a V-8 engine with the following features: dual overhead camshafts four valves per cyl ...