Ford 2003 Mustang Workshop Manual page 3054

2. Inspect to determine if one of the following mechanical or electrical concerns apply:
Visual Inspection Chart
Loose, missing or damaged A/C compressor
drive belt.
Loose or disconnected A/C clutch.
Loose, misrouted or damaged vacuum lines.
Broken or leaking refrigerant lines.
Broken or leaking vacuum control motor.
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
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
P1460 WOT A/C cutout circuit
malfunction
P1464 A/C demand out of self-test
range
Symptom Chart
Mechanical
Refer to the Powertrain Control/Emissions Diagnosis
(PC/ED) manual.
GO to DTC P1464.
Open fuses.
Blower motor inoperative.
A/C compressor inoperative.
a Circuitry open/shorted.
Disconnected electrical
connectors.
Section 418-00
to diagnose network concern.
Action
Electrical