warning FORD FESTIVA 1991 User Guide

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WIRING DIAGRAMS
1991 WIRING DIAGRAMS Ford Motor Co.
IDENTIFICATION
COMPONENT LOCATION MENU
COMPONENT LOCATIONS
WIRING DIAGRAMS
ComponentFigure No. (Location)
A/C RELAY3 (B 8)
A/T SELECT LIGHT3 (E 8)
ALTERNATOR1 (C 3)
BACK-UP LIGHT SWITCH5 (D 19)
BATTERY1 (A 2)
BLOWER SWITCH3 (C 9)
BRAKE WARNING SWITCH1 (C 2)
CIG LTR4 (E 14)
CLUTCH INTERLOCK SWITCH (M/T)1 (B 2)
CONDENSER FAN (A/T)3 (C 8)
COOLANT FAN MOTOR1 (D 3)
COOLANT FAN RELAY1 (D 3)
DEFOG SWITCH5 (C 16)
DIR/HAZARD SWITCH4 (B-C 12)
ELECT CONTROL ASSY (ECA)2 (A 4-7)
FRONT WASHER MOTOR1 (E 3)
FRONT WIPER MOTOR1 (E 3)
FRONT WIPER/WASHER SWITCH5 (A 16)
FUEL PUMP INERTIA SWITCH2 (D 4)
FUEL PUMP RELAY2 (C 4)
FUSE BLOCK3 (D-E 9-10)
HEADLIGHT RELAY4 (D 14)
HORN RELAY3 (E 11)
HORN SWITCH4 (E 15)
IGNITION COIL2 (E 5)
IGNITION KEY REMINDER SWITCH4 (E 13)
IGNITION SWITCH3 (C-D 11)
INSTRUMENT CLUSTER4 (A-E 15)
INSTRUMENT PANEL LIGHT CONTROL4 (D-E 12)
INTERIOR LIGHT SWITCH4 (E 14)
LIGHT SWITCH4 (C-D 12)
MAIN FUSE PANEL1 (A 3)
MAIN RELAY2 (D 5)
NEUTRAL SAFETY SWITCH (A/T)1 (B 2)
PARKING LIGHT RELAY4 (C 14)
PASSIVE RESTRAINT CONTROL MODULE3 (A 11)
REAR WASHER MOTOR5 (D 17)
REAR WIPER/WASHER SWITCH5 (E 16)
SHIFT LOCK SERVO ASSY4 (A 12)
STARTER1 (B 3)
STOP LIGHT SWITCH5 (D 19)
TIMER/BUZZER UNIT4 (E 12)
TRUNK LIGHT5 (B 16)
WAC RELAY3 (B 8)
Page 1 of 6 MITCHELL 1 ARTICLE - WIRING DIAGRAMS 1991 WIRING DIAGRAMS Ford Motor Co.
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ELECTRONIC CONTROL ASSEMBLY (ECA)
REMOVAL & INSTALLATION
Disconnect negative battery cable. On Festiva, from under instrument panel, remove heater duct. On Capri, disengage push-pin retainers by
pulling back on front edges of both center carpet panels. Remove carpet panel retaining screws and panels. Disconnect ECA wire harness
connector. Remove ECA bolts and ECA. To install, reverse removal procedure. On Festiva, ensure mounting clip is inserted into bulkhead
recess.
FUEL SYSTEM
FUEL SYSTEM PRESSURE RELEASE
Remove rear seat assembly. With engine running, disconnect fuel pump connector. Run engine until it stalls to relieve fuel line pressure.
FUEL INJECTORS
Removal
Relieve fuel system pressure. On Capri, remove throttle body. On Festiva, remove intake plenum. See INTAKE PLENUM. Remove fuel inlet
and fuel return line from fuel rail. Remove electrical connectors from injectors. Remove pressure regulator. See Fig. 4
. Remove fuel rail
attaching bolts and fuel rail. Remove fuel injectors.
Installation
Install NEW "O" rings on fuel injectors and lubricate with gasoline. Install fuel injectors into cylinder head. Install fuel rail onto fuel injectors.
Install fuel rail attaching bolts. To complete installation, reverse removal procedure. Check system for leaks.

Fig. 4: Exploded View of Fuel Control System

Courtesy of FORD MOTOR CO.
FUEL PUMP
Removal
Remove fuel tank sending unit. Remove fuel filter from pump. Remove fuel pump wires from sending unit. Remove retaining clamp screw and
clamp. Remove rubber retaining band (if equipped). Remove fuel pump from sending unit.
Installation
To install, reverse removal procedure. Check system for leaks.
INTAKE PLENUM WARNING:ALWAYS relieve fuel pressure before disconnecting any fuel injection-related com ponent. DO NOT
allow fuel to contact engine or electrical com ponents.
WARNING:ALWAYS relieve fuel pressure before disconnecting any fuel-related com ponent. DO NOT allow fuel to
contact engine or electrical com ponents.
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Removal
Drain radiator and remove negative battery cable. Disconnect throttle cable. Remove air duct from throttle body. Disconnect throttle position
sensor/switch connector. Mark all coolant and vacuum hoses for reassembly reference and remove from throttle body. See Fig. 4
. Remove
intake plenum bolts and remove intake plenum and gasket.
Installation
To install, reverse removal procedure. Use NEW intake plenum-to-intake manifold gasket. Tighten bolts to specification, see TORQUE
SPECIFICATIONS at end of article.
OXYGEN (O2) SENSOR
Removal & Installation
Disconnect negative battery cable. Disconnect wire harness connector, and remove oxygen sensor. If exhaust sensor is difficult to remove, use
rust penetrant to avoid possible damage to exhaust threads. If new sensor is not pre-coated with anti-seize, apply anti-seize compound to
sensor threads. DO NOT remove anti-seize from sensor. To install, tighten sensor and attach wire harness connector.
THROTTLE BODY
Removal & Installation
Drain radiator and remove negative battery cable. Remove resonance chamber. Disconnect throttle cable. Remove air duct. Mark all coolant
and vacuum hoses for reassembly reference and remove from throttle body. Disconnect throttle position sensor/switch connector. Remove
throttle body nuts and bolts. Remove throttle body and gasket. To install, reverse removal procedure using NEW throttle body-to-intake
plenum gasket.
THROTTLE POSITION SENSOR/SWITCH
Removal & Installation
Disconnect negative battery cable. Disconnect throttle position sensor/switch connector. Remove attaching bolts. Remove sensor/switch from
throttle body. To install, reverse removal procedure.
TURBOCHARGER
Removal
1. Drain radiator and remove negative battery cable. Remove throttle body air intake tube. Disconnect intercooler hose from turbocharger
assembly. Disconnect O2 sensor. Remove lower heat shield retaining bolts and lower heat shield from turbocharger. Remove upper heat
shield retaining bolts and upper heat shield from exhaust manifold.
2. Slide O2 sensor wire and guide through upper heat shield. Remove side heat shield retaining bolts from turbocharger, and remove sid e
heat shield. Remove power steering belt. Remove power steering pump through bolt and adjuster nuts and bolts. Disconnect lower
radiator hose from water pump.
3. Pull pump from bracket, and position pump to access mounting bracket retaining nut and bolts. Remove mounting bracket-to-engine nut
and bolts and remove bracket. Remove air cleaner duct retaining screws. Loosen clamp at turbocharger and move duct tube out of way.
Disconnect coolant supply hose at turbocharger.
4. Remove bolt and sealing washers attaching oil supply line at engine block. Raise vehicle on hoist. Remove nuts and washers from
exhaust pipe flange. Remove bolts attaching exhaust hanger to engine block. Slide rubber exhaust hangers from catalytic converter. Pull
exhaust pipe downward and to left side of vehicle. Disconnect oil return hose from turbocharger. Disconnect coolant return hose fro m
turbocharger.
5. Remove turbocharger support bracket retaining bolts. Remove coolant by-pass tube outlet-to-water pump bolts. Lower vehicle. Loosen
retaining clamp bolt on coolant by-pass tube at rear of cylinder head. Remove 11 retaining nuts from exhaust manifold. Position coolant
by-pass tube out of way after pulling bracket from exhaust stud.
6. Remove exhaust manifold by pulling off studs and moving assembly towards right side of engine compartment, clearing cooling fan.
With assembly removed from vehicle, remove turbocharger-to-exhaust manifold nuts. Separate assembly and discard gasket.
Installation
1. Install NEW gasket on exhaust manifold and install turbocharger onto studs. Install turbocharger-to-exhaust manifold nuts. Remo ve o il
supply line from turbocharger. Install NEW exhaust gasket on cylinder head. Install turbocharger and exhaust manifold assembly onto
studs. Install coolant by-pass tube bracket onto exhaust stud. Install 11 retaining nuts onto exhaust manifold.
2. Securely tighten heater tube clamp bolt. Raise vehicle. Install coolant by-pass tube outlet-to-water pump bolts. Install turbocharger
support bracket retaining bolts. Connect coolant return hose to turbocharger. Connect oil return hose to turbocharger. Install exhaust
pipe onto turbocharger, and hand tighten nuts and washers. Install bolts attaching exhaust hanger to engine block.
3. Slide rubber exhaust hangers onto catalytic converter. Tighten exhaust pipe nuts and washers. Lower vehicle. Install bolt and sealing
washers attaching oil supply line at engine block. Install oil supply line onto turbocharger. To complete installation, reverse removal
procedure. Tighten bolts and nuts to specification, see TORQUE SPECIFICATIONS
at end of article. NOTE:T o prevent dust and dirt from entering intake m anifold ports, cover ports with clean cloth after
rem oving intake plenum .
WARNING:DO NOT rem ove oxygen sensor when engine is hot.
NOTE:Clean throttle body exterior before rem oval.
CAUT ION: Before installing turbocharger, put .8 oz. (25 m l) engine oil into turbocharger oil inlet.
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F - BASIC TESTING
1991-92 ENGINE PERFORMANCE Ford Motor Co. Basic Diagnostic Procedures
INTRODUCTION
The following diagnostic steps help prevent overlooking simple problems and begin diagnosis for a no-start condition.
The first step in diagnosing any driveability problem is to verify the complaint. Test drive the vehicle under the conditions in which the
problem reportedly occurred.
Before entering self-diagnostics, perform a careful and complete visual inspection. Most engine control problems result from mechanical
breakdowns, poor electrical connections or damaged/misrouted vacuum hoses. Before condemning the computerized system, perform each test
listed in this article.
PRELIMINARY INSPECTION & ADJUSTMENTS
VISUAL INSPECTION
Perform a visual inspection of all electrical wiring. Look for chafed, stretched, cut or pinched wiring. Ensure electrical connections fit tightly
and are not corroded. Ensure vacuum hoses are properly routed and are not cut or pinched. If necessary, see VACUUM DIAGRAMS article in
the ENGINE PERFORMANCE Section to verify routing and connections. Inspect air induction system for possible vacuum leaks.
MECHANICAL INSPECTION
Compression
Engine mechanical condition can be checked using a compression gauge, vacuum gauge or engine analyzer. See engine analyzer instruction
manual for specific instructions. Lowest compression reading must be not less than 75 percent of highest reading.
Exhaust System Backpressure
Exhaust system can be checked with a vacuum gauge or a 0-5 psi pressure gauge. If a pressure gauge is used, remove O2 sensor. Connect gauge
to O2 sensor port. Start engine, and run at 2500 RPM. If exhaust system backpressure is more than 2 psi, exhaust system or catalytic converter
is plugged.
If a vacuum gauge is used, connect it to intake manifold vacuum. Start engine. Observe vacuum gauge. Open throttle part way and hold steady.
If vacuum gauge drops slowly after stabilizing, check exhaust system for a restriction.
FUEL PRESSURE
Fuel Pressure Release
Start engine (if possible), and unplug VAF meter connector. When engine stalls, turn ignition off and reconnect VAF meter wiring. Usin g sh o p
towel, cover fitting to absorb leakage when opening fuel system.
Fuel Pressure Check
1. Connect fuel pressure gauge between fuel filter and fuel rail. Open main valve, and close drain valve. Locate fuel pump check connector
in engine compartment, near left strut. Connect jumper wire between fuel pump test terminals (Black and Green/White wires on Capri
or Black and Green/Red wires on Festiva).
2. Turn ignition on to activate fuel pump. If pump does not run, check fuel pump circuit. If possible, start engine. Measure and record fuel
pressure. For fuel pressure specifications, see FUEL PRESSURE SPECIFICATIONS
article. Disconnect vacuum from pressure
regulator. Turn engine off. Wait 5 minutes and ensure residual pressure is at least 21 psi (1.5 kg/cm
2 ).
3. Operate fuel pump by reconnecting jumper wire at fuel pump check connector. Check fuel pump performance. Pinch hose between
pressure gauge and fuel filter. Do not hold longer than necessary to check pressure.For fuel pressure specifications, see FUEL
PRESSURE SPECIFICATIONS article. If pump does not meet specifications, check fuel pump circuit, fuel pump, fuel tank and fuel
filter or replace fuel pump.
FUEL PUMP PERFORMANCE NOTE:Unless stated otherwise in test procedure, perform all voltage tests with a Digital Volt-Ohm m eter
(DVOM) with a m inim um 10-m egohm input im pedance.
CAUT ION: DO NOT use ignition switch during com pression tests on fuel injected vehicles. Fuel injectors are
triggered by ignition switch during cranking m ode. Use a rem ote starter to crank engine to prevent fire
hazard and catalytic converter and engine oiling system contam ination.
WARNING:ALWAYS relieve fuel pressure before disconnecting any fuel injection system com ponent. DO NOT
allow fuel to contact engine or electrical com ponents.
NOTE:For 1991 fuel pressure specifications, see FUEL PRESSURE SPECIFICAT IONS
article. For 1992 fuel
pressure specifications, see FUEL PRESSURE SPECIFICAT IONS
article.
ApplicationPressure psi (kg/cm2 )Min. Vol. in 10 sec. Ozs. (cc)
Capri(1) 5.5 (167)
Festiva(1) 7.4 (220)
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gases into harmless substances.
PCV VALVE
The Positive Crankcase Ventilation (PCV) valve, located in the valve cover, controls the flow of blow-by gas from the crankcase to the intake
man ifo l d .
SELF-DIAGNOSTIC SYSTEM
The ECA monitors its inputs and outputs. When it detects a malfunction, it sets a code in the ECA and sends a signal to the CHECK ENGINE
warning light. The light remains on until the malfunction is repaired. Trouble codes may be accessed at the Self-Test Output (STO) and Self-
Test Input (STI) connectors, near the battery.
If a sensor fails, the ECA will use a substitute value in its calculations to permit continued engine operation. In this condition, the vehicle will
run, but driveability may be poor. Intermittent failures may result in the CHECK ENGINE warning light flickering or going out after the fault
goes away. The corresponding trouble code, however, will be stored in the ECA. If fault does not recur, the related code will be erased from
ECA memory.
CHECK ENGINE LIGHT
Hard failures cause the CHECK ENGINE warning light to come on and remain on until the malfunction is repaired. If the warning light comes
on and stays on during vehicle operation, determine and correct the cause of the malfunction. NOTE:For additional inform ation and operating procedures for the self-diagnostic system , refer to T EST S
W/CODES article in the ENGINE PERFORMANCE Section.
Copyr ight 2009 Mitchell Repair Information Company, LLC. All Rights Reserved.
Article GUID: A00022697
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GENERAL INFORMATION
T rouble Shooting - Basic Procedures
* PLEASE READ THIS FIRST *
ACCESSORIES & ELECTRICAL
CHARGING SYSTEM TROUBLE SHOOTING
BASIC CHARGING SYSTEM TROUBLE SHOOTING CHART NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. T he purpose of this T rouble Shooting inform ation is to provide a list
of com m on causes to problem sym ptom s. For m odel-specific T rouble Shooting, refer to SUBJECT ,
DIAGNOST IC, or T EST ING articles available in the section(s) you are accessing.
NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. T he purpose of this T rouble Shooting inform ation is to provide a list
of com m on causes to problem sym ptom s. For m odel-specific T rouble Shooting, refer to SUBJECT ,
DIAGNOST IC, or T EST ING articles available in the section(s) you are accessing.
NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. T he purpose of this T rouble Shooting inform ation is to provide a list
of com m on causes to problem sym ptom s. For m odel-specific T rouble Shooting, refer to SUBJECT ,
DIAGNOST IC, or T EST ING articles available in the section(s) you are accessing.
CONDITION & POSSIBLE CAUSECORRECTION
Vehicle Will Not Start
Dead batteryCheck battery cells, alternator
belt tension and alternator
output
Loose or corroded battery connectionsCheck all charging system
connections
Ignition circuit or switch malfunctionCheck and replace as necessary
Alternator Light Stays On With Engine Running
Loose or worn alternator drive beltCheck alternator drive tension
and condition, See Belt
Adjustment in TUNE-UP article
in the TUNE-UP section
Loose alternator wiring connectionsCheck all charging system
connections
Short in alternator light wiringSee Indicator Warning Lights in
STANDARD INSTRUMENTS
in the ACCESSORIES &
EQUIPMENT section
Defective alternator stator or diodesSee Bench Tests in
ALTERNATOR article
Defective regulatorSee Regulator Check in
ALTERNATOR article
Alternator Light Stays Off With Ignition Switch ON
Blown fuseSee WIRING DIAGRAMS
Defective alternatorSee Testing in ALTERNATOR
article
Defective indicator light bulb or socketSee Indicator Warning Lights in
STANDARD INSTRUMENTS
in the ACCESSORIES &
EQUIPMENT section
Alternator Light Stays OFF With Ignition Switch ON
Short in alternator wiringSee On-Vehicle Tests in
ALTERNATOR article
Defective rectifier bridgeSee Bench Tests in
ALTERNATOR article
Lights or Fuses Burn Out Frequently
Defective alternator wiringSee On-Vehicle Tests in
ALTERNATOR article
Defective regulatorSee Regulator Check in
ALTERNATOR article
Defective batteryCheck and replace as necessary
Ammeter Gauge Shows Discharge
Loose or worn drive beltCheck alternator drive belt
tension and condition. See Belt
Adjustment in TUNE-UP article
in the TUNE-UP section
Defective wiringCheck all wires and wire
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AIR CONDITIONING & HEAT
AIR CONDITIONING TROUBLE SHOOTING
BASIC AIR CONDITIONING TROUBLE SHOOTING CHART
HEATER SYSTEM TROUBLE SHOOTING
BASIC HEATER SYSTEM TROUBLE SHOOTING CHART
Broken lead or loose soldered connectionsRepair wire or wire
connections as necessary
Solenoid Plunger Vibrates When Switch is Engaged
Weak batteryCharge or replace battery as
necessary
Solenoid contacts corrodedClean contacts or replace
solenoid
Faulty wiringCheck all wiring leading to
solenoid
Broken connections inside switch coverRepair connections or replace
solenoid
Open hold-in wiresolenoid
Low Current Draw
Worn brushes or weak brush springsReplace brushes or brush
springs as necessary
High Pitched Whine During Cranking Before Engine Fires but Engine Fires and Cranks Normally
Distance too great between starter pinion and flywheelAlign starter or check that
correct starter and flywheel are
being used
High Pitched Whine After Engine Fires With Key released. Engine Fires and Cranks Normally
Distance too small between starter pinion and flywheelFlywheel runout contributes to
the intermittent nature
WARNING:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. T he purpose of this T rouble Shooting inform ation is to provide a list
of com m on causes to problem sym ptom s. For m odel-specific T rouble Shooting, refer to SUBJECT ,
DIAGNOST IC, or T EST ING articles available in the section(s) you are accessing.
CONDITIONPOSSIBLE CAUSE
Compressor Not WorkingCompressor clutch circuit open.
.....Compressor clutch coil inoperative.
.....Poor clutch ground connection.
.....Fan belts loose.
.....Thermostatic switch inoperative.
.....Thermostatic switch not adjusted.
.....Ambient temperature switch open.
.....Superheat fuse blown.
Excessive Noise or VibrationMissing or loose mounting bolts.
.....Bad idler pulley bearings.
.....Fan belts not tightened correctly.
.....Compressor clutch contacting body.
.....Excessive system pressure.
.....Compressor oil level low.
.....Damaged clutch bearings.
.....Damaged reed valves.
.....Damaged compressor.
In su fficien t o r No Co o l in g; Co mp resso r
WorkingExpansion valve inoperative.
.....Heater control valve stuck open.
.....Low system pressure.
.....Blocked condenser fins.
.....Blocked evaporator fins.
.....Vacuum system leak.
.....Vacuum motors inoperative.
.....Control cables improperly adjusted.
.....Restricted air inlet.
.....Mode doors binding.
.....Blower motor inoperative.
.....Temperature above system capacity.
NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. T he purpose of this T rouble Shooting inform ation is to provide a list
of com m on causes to problem sym ptom s. For m odel-specific T rouble Shooting, refer to DIAGNOST IC,
or T EST ING articles available in the section(s) you are accessing.
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GENERAL INFORMATION
Electrostatic Discharge (ESD) Warning - Basic Inform ation
* PLEASE READ THIS FIRST *
INTRODUCTION
All Electrostatic Discharge (ESD) sensitive components contain solid state circuits (transistors, diodes, semiconductors) that may become
damaged when contacted with an electrostatic charge. The following information applies to all ESD sensitive devices. The ESD symbol shown
in Fig. Fig. 1
may be used on schematics to indicate which components are ESD sensitive. See Fig. 1. Although different manufactures may
display different symbols to represent ESD sensitive devices, the handling and measuring precautions and procedures are the same.

Fig. 1: Sample ESD Symbol

HANDLING STATIC-SENSITIVE CIRCUITS/DEVICES
When handling an electronic part that is ESD sensitive, the technician should follow these guidelines to reduce any possible electrostatic
charge build-up on the technician's body and the electronic part.
1. Always touch a known good ground source before handling the part. This should be repeated while handling the part and more
frequently after sitting down from a standing position, sliding across the seat or walking a distance.
2. Avoid touching electrical terminals of the part, unless instructed by a diagnostic procedure.
3. DO NOT open the package of a new part until it is time to install the part.
4. Before removing the part from its package, ground the package to a known good ground source.
CHECKING STATIC-SENSITIVE CIRCUITS/DEVICES
1. Solid State circuits in electronic devices are shown greatly simplified in schematics. See Fig. 2. Due to the simplification of the NOTE:T his article is intended for general inform ation purposes only. Contents are generic in nature and all
inform ation m ay or m ay not apply to all vehicles.
NOTE:T his article is intended for general inform ation purposes only. Contents are generic in nature and all
inform ation m ay or m ay not apply to all vehicles.
NOTE:T his article is intended for general inform ation purposes only. Contents are generic in nature and all
inform ation m ay or m ay not apply to all vehicles.
NOTE:T his article is intended for general inform ation purposes only. Contents are generic in nature and all
inform ation m ay or m ay not apply to all vehicles.
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electronic devices on the schematic, resistance measurements could be misleading or could lead to an electrostatic discharge. Always
follow the recommended diagnostic procedure.

Fig. 2: Sample Schematic Showing Typical ESD Sensitive Device

2. Only measure resistance at the terminals of the devices when instructed by the recommended diagnostic procedure.
3. When using a voltmeter, be sure to connect the ground lead first.
Copyr ight 2009 Mitchell Repair Information Company, LLC. All Rights Reserved.
Article GUID: A00130228
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SCREW TYPE SEAL CANS
Ensure can tap is fully closed. Screw refrigerant can into can tap fitting until tight. This will pierce the can. Connect tap to center hose on
manifold gauge set. DO NOT open tap until ready to dispense R-12 into system.
CONNECTING LINES & FITTINGS
1. A new "O" ring should be used in all instances when connecting lines and fittings (dip "O" ring in clean refrigeration oil and make
certain it is not twisted during installation). Always use two wrenches to avoid twisting or distorting lines and fittings, tighten coupling
nuts securely.
2. Ford spring-coupling fittings require a special coupling tool (Motorcraft YT-1056) to open or close. Use the following procedure to
connect or disconnect the spring-coupling fitting.
Ford Spring-Coupling Fitting
1. Discharge system using approved refrigerant recovery/recycling equipment. Place proper end of tool over refrigerant line. Tool fits both
3/8" and 1/2" fittings. Push tool into fitting cage to release spring inside. Pull lines apart and remove tool.
2. Before connecting, check internal spring for damage. If necessary, pry spring out and replace it. Clean fittings and install new "O" rings.

Fig. 1: Assembling Ford Spring
-Coupling Fitting
PLACING SYSTEM IN OPERATION
After component replacement and/or system servicing has been completed and all connections have been made, proceed as follows:
1. Evacuate the system using a vacuum pump.
2. Charge the system with new R-12 (refrigerant) according to each individual vehicle as outlined in the GENERAL SERVICING article.
Also see Refrigerant Capacity in this Section.
3. Leak test the system, with particular attention to all new connections and components.
4. Make a performance test of the system. Never assume that a recharging has automatically corrected a problem.
COMPRESSOR REMOVAL INFORMATION - ISOLATION METHOD
On systems which have compressors equipped with stem-type service valves (Tecumseh), it is possible to isolate the compressor for removal.
Isolating
Turn both high and low pressure manual valves to extreme clockwise (front seat) position. Loosen cap on high pressure manual valve
connection to compressor and allow gas to escape until compressor is relieved of pressure.
COMPRESSOR REMOVAL INFORMATION-DISCHARGE METHOD
This procedure is to be used on vehicles which have compressor equipped with Schrader service valves. In these cases, the compressor cannot
be isolated and the system must be discharged, using approved refrigerant recovery/recycling equipment, prior to compressor removal. WARNING:DO NOT open high side hand valve while air conditioning system is in operation. T his high pressure
could rupture can or fitting at safety can valve, resulting in dam age and personal injury.
CAUT ION: Use ONLY "O" rings designed for these Ford fittings (Motorcraft YF-982). Norm al refrigerant "O" rings
will NOT seal.
Copyr ight 2009 Mitchell Repair Information Company, LLC. All Rights Reserved.
Article GUID: A00039191
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