radio FORD FESTIVA 1991 User Guide

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GENERAL INFORMATION
Parasitic Load Explanation & T est Procedures
* PLEASE READ THIS FIRST *
GENERAL INFORMATION
The term Parasitic Load refers to electrical devices that continue to use or draw current after the ignition switch is turned to OFF position. This
small amount of continuous battery draw is expressed in milliamps (mA). On Chrysler vehicles, a typical Parasitic Load should be no more
than 30 milliamps (0.030 amps). On Ford Motor Co. and General Motors vehicles produced after 1980, a typical Parasitic Load should be no
more than 50 milliamps (0.050 amps).
Vehicles produced since 1980 have memory devices that draw current with ignition off for as long as 20 minutes before shutting down the
Parasitic Drain. When Parasitic Load exceeds normal specifications, the vehicle may exhibit dead battery and no-start condition.
Follow test procedure for checking Parasitic Loads to completion. A brief overview of a suggested test procedure is included along with some
typical Parasitic Load specifications. Refer to GENERAL MOTORS PARASITIC LOAD TABLE chart.
TESTING FOR PARASITIC LOAD
The battery circuit must be opened to connect test switch (shunt) and ammeter into the circuit. When a battery cable is removed, timer circuits
within the vehicle computer are interrupted and immediately begin to discharge. If in doubt about the condition of the ammeter fuse, test it
with an ohmmeter prior to beginning test. An open fuse will show the same reading (00.00) as no parasitic drain. Begin test sequence with the
meter installed and on the 10-amp scale. Select lower scale to read parasitic draw.
CHRYSLER IGNITION OFF DRAW (IOD) TEST
To test for excessive IOD, verify that all electrical accessories are OFF. Turn off all lights, remove ignition key, and close all doors and decklid.
If the vehicle is equipped with electronic accessories (illuminated entry, automatic load leveler, body computer, or high line radio), allow the
system to automatically shut off (time out), up to 3 minutes.
1. Raise the hood and disconnect both battery cables, negative first.
2. Reconnect the negative cable and connect a typical 12-volt test light (low wattage bulb) between the positive cable clamp and the
positive battery post. Remove the engine compartment lamp bulb. If the test light does not light, proceed to step 3
. If the test light does
light, proceed to step, 4
. The test light will indicate IOD greater than 3 amps. After higher amperage IOD has been corrected, proceed to
step 3
.
3. ith 12-volt test light still connected (not lit), connect an ammeter (milliampere scale) between the positive cable clamp and the positive
battery post, disconnect test light, refer to instructions provided with ammeter being used. A reading of 30 milliamperes or less indicates
normal electrical draw. If ammeter reads more than 30 milliamperes, excessive IOD must be corrected.
4. Locate the fuse panel and remove fuses or circuit breakers one at a time, and observe ammeter after each fuse or circuit breaker is
removed. If test light goes out and the reading drops below 30 milliamperes when a certain fuse or circuit breaker is removed, that circuit
may have a defect.
5. If IOD is detected after all fuses and circuit breakers have been removed, disconnect the 60-way connector at the Single Module Engine
Control (SMEC), located outboard of the battery.
6. If excessive IOD is detected after all fused circuits and SMEC have been verified, disconnect the B+ terminal from the alternat o r. If
reading drops below 30 milliamperes, reinstall all fuses and circuit breakers, reconnect B+ terminal at alternator, reconnect battery, and
perform alternator diagnostics.
7. Install engine compartment lamp bulb.
TEST PROCEDURE USING TEST SWITCH
1. Turn ignition off. Remove negative battery terminal cable. Install Disconnect Tool (J-38758) test switch male end to negative battery
cable. Turn test switch knob to OFF position (current through meter). Install negative battery cable to the female end of test switch. NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. For m odel-specific inform ation see appropriate articles where
available.
NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. For m odel-specific inform ation see appropriate articles where
available.
NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. For m odel-specific inform ation see appropriate articles where
available.
CAUT ION: Always turn ignition off when connecting or disconnecting battery cables, battery chargers or jum per
cables. DO NOT turn test switch to OFF position (which causes current to run through am m eter or
vehicle electrical system ).
NOTE:Mem ory functions of various accessories m ust be reset after the battery is reconnected.
CAUT ION: IOD greater than 3 am ps m ay dam age m illam pm eter.
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2. Turn test switch knob to ON position (current through switch). Road test vehicle with vehicle accessories on (radio, air conditioner, etc).
After road test, turn ignition switch to LOCKED position and remove key. Connect ammeter terminals to test switch terminals. See Fig.
1. Select 10-amp scale.
3. Turn off all electrical accessories. Turn off interior lights, underhood lamp, trunk light, illuminated entry, etc. To avoid damaging
ammeter or obtaining a false meter reading, all accessories must be off before turning test switch knob to OFF position.
4. Turn test switch knob to OFF position to allow current to flow through ammeter. If meter reads wrong polarity, turn test switch to ON
position and reverse leads. Turn test switch to OFF position. Observe current reading. If reading is less than 2 amps, turn test switch to
ON position to keep electrical circuits powered-up.
5. Select low amp scale. Switch lead to the correct meter position. Turn test switch to OFF position and compare results to normal current
draw. See GENERAL MOTORS PARASITIC LOAD TABLE (MILLIAMPS)
. If current draw is unusually high for the vehicle's
overall electrical system, remove system fuses one at a time until current draw returns to normal.
6. Turn test switch to ON position each time door is opened or fuse is removed. Turn switch to OFF position to read current draw va l u e
through meter. When the cause of excessive current drain has been located and repaired, remove test switch and reconnect negative
battery cable to the negative battery terminal.
INTERMITTENT PARASITIC LOAD PROBLEMS
Intermittent parasitic load can occur because of a memory device that does not power down with ignition off. With an intermittent parasitic
load, battery draw can be greater than 1.0 amp.
To find an intermittent problem requires that an ammeter and Disconnect Tool (J-38758) test switch be connected and left in the circuit. See
Fig. 1
. Road test vehicle. After road test, turn ignition off and remove key.
Monitor the milliamps scale for 15-20 minutes after ignition is turned off. This allows monitoring memory devices to determine if they time out
and stop drawing memory current. The test switch is needed to protect ammeter when the vehicle is started.

Fig. 1: Connecting Kent
-Moore Disconnect Tool (J-38758)
Courtesy of GENERAL MOTORS CORP.
GENERAL MOTORS PARASITIC LOAD
ComponentNormal DrawMaximum DrawTime-Out (Minutes)
Anti-Theft System0.41.0.....
Auto Door Lock1.01.0.....
Body Control Module3.612.420
Central Processing System1.62.720
Electronic Control Module5.610.0.....
Electronic Level Control2.03.320
Heated Windshield Module0.30.4.....
HVAC Power Module1.01.0.....
Illuminated Entry1.01.01
Light Control Module0.51.0.....
Oil Level Module0.10.1.....
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DIODE CHECK & SOLENOID TEST

Fig. 2: Diode Check & Solenoid Test

Courtesy of GENERAL MOTORS CORP.
QUAD DRIVER TEST

Fig. 3: Quad Driver Test

Courtesy of GENERAL MOTORS CORP.
Multi-Function Chime1.01.0.....
Pass Key Decoder Module0.751.0.....
Power Control Module5.07.0.....
Retained Accessory Power3.83.8.....
Radio7.08.015
Twilight Sentinel Module1.01.0.....
Voltage Regulator1.42.0.....
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5. Check blower motor fan switch continuity. Resistance should not exceed 4 ohms. See BLOWER MOTOR FAN SWITCH
CONTINUITY table. If continuity is not present, replace fan switch. If continuity is okay, repair open in Black wire from blower motor
switch to ground.
BLOWER MOTOR FAN SWITCH CONTINUITY
REMOVAL & INSTALLATION
CONTROL PANEL
1. Remove bezel screws and accessory bezel. Remove radio. Remove 4 screws securing control panel to instrument panel. Remove glove
box attaching screws and glove box. Remove the retaining clip and disconnect fresh/recirculation air door cable from mode door lever.
2. Disconnect mode select cable at mode control door lever. Disconnect temperature control cable at temperature control mode door lever.
Pull control panel away from instrument panel. Disconnect blower motor switch connector. Disconnect illumination electrical
connector. Remove control panel. To install, reverse removal procedure. Adjust control cables. See ADJUSTMENTS in this article.
BLOWER MOTOR FAN SWITCH
Remove control panel. See CONTROL PANEL R & I
. Remove blower motor fan switch knob. Remove attaching nut. To install, reverse
removal procedure.
HEATER CORE
1. Disconnect negative battery cable. Remove steering wheel by prying out center trim insert and removing steering wheel retaining nut.
Remove 2 steering wheel cover retaining screws and remove cover. Using a steering wheel puller, remove steering wheel.
2. Remove 5 screws and remove lower and upper steering column covers. Disconnect electrical connections and remove multifunction
switch. Remove 5 screws and pull instrument cluster hood rearward. Disconnect electrical connections and remove instrument cluster
hood.
3. Disconnect speedometer cable at transaxle. Remove 4 instrument cluster screws. Pull instrument cluster rearward and disconnect
speedometer cable and electrical connections. Remove instrument cluster.
4. Remove 2 center bracket mounting bolts under steering column and remove bracket. Remove glove box attaching screws and remove
glove box. Remove left and right heater ducts. Remove fuse panel cover. Remove 2 screws securing fuse panel and push fuse panel
inward. DO NOT remove fuse panel.
5. Slide both seats to most forward position. Remove 2 console attaching screws, located in front of seat belt anchors. Slide both seats to
rearmost position. Remove parking brake console insert. Using a Phillips screwdriver, remove push retainer insert, located at front lower
edge of parking brake console. Pull back on parking brake lever and remove parking brake console.
6. Remove gearshift knob. Remove screws and remove shift console. Remove radio/heater control panel bezel screws and remove bezel.
Remove 4 radio attaching screws. Pull radio out and disconnect antenna lead and electrical connections. Disconnect radio ground lead
and remove radio.
7. Remove 4 screws attaching heater control panel. Disconnect control cables and electrical connections. Remove control panel, while
pulling cables through opening.
8. Pry out bolt cover trim inserts in top corners of dash. Remove bolts located under trim panels. Remove 7 instrument panel attaching
bolts and 2 nuts. Pull instrument panel rearward. Disconnect any harness connectors and clips. Remove instrument panel.
9. Disconnect electrical connections at blower and resistor. Remove harness from routing brackets on heater box. Loosen clamp screw
securing air inlet housing. Remove attaching nuts at top and bottom of heater box. Disconnect defroster ducts and remove heater
assembly.
10. Disconnect link connecting 2 defroster doors. Remove attaching screw just above and to right of blower resistor. Turn heater assembly
around and remove screw just to left of blower motor opening. Remove clips securing 2 halves of heater assembly. Separate halves. Lift
out heater core.
11. To install, reverse removal procedure. Ensure all heater control cables are routed and adjusted properly. See ADJUSTMENTS in this
article. Fill cooling system. Check for leaks.
BLOWER MOTOR & RESISTOR
Disconnect negative battery cable. Remove instrument panel spacer brace located below steering column. Remove airflow duct below steering
column. Disconnect blower motor or resistor wiring. Remove 3 blower motor attaching screws or 2 resistor attaching screws and remove
component. To install, reverse removal procedure.
Switch PositionContinuity Between Wire Colors
1Black-to-Blue/White
2Black-to-Blue/Yellow & Blue/Yellow-to-Blue/Red
3Black-to-Blue/Black & Blue/Black-to-Blue/Red
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Fig. 2: Identifying A/C
-Heater Air Distribution Components
Courtesy of FORD MOTOR CO.
OPERATION
A/C-HEATER CONTROL PANEL
The A/C-heater panel is located in the center of instrument panel above the radio. Air discharge outlets are located above, below, in center
and on both sides of instrument panel. The climate control panel consists of 3 slide levers, one A/C on-off push button and a rotary blower
switch.
The lower slide lever is used to control temperature. Sliding lever from far left side (cool) to far right side (warm) increases interior
temperature. The middle slide lever selects fresh air from outside or recirculated air from inside. The upper slide lever controls air delivery
mode. A/C push-button on-off switch activates air conditioning system.
THERMOSTATIC SW ITCH
With A/C system operating, thermostatic switch determines A/C compressor clutch on-time. Control is accomplished by a cable attached
between the temperature blend lever and thermostatic switch. The thermostatic switch sensing tube is installed into (or near) evaporator fins.
Switch is wired in series with A/C relay and Electronic Control Assembly (ECA). The ECA calculates compressor on-time based on A/C relay
signals. This controls evaporator temperature to regulate cool air entering vehicle.
THERMOSTATIC EXPANSION VALVE
The Thermostatic Expansion Valve (TXV) is a controlling device metering liquid refrigerant from high pressure line into evaporator. It also
provides for complete vaporization of all refrigerant entering evaporator.
The high refrigerant pressure is reduced before entering evaporator by a ball valve within TXV. Depending on pressure applied to TXV
diaphragm from both sides of system, TXV allows more or less high pressure refrigerant to be discharged through its orifice into evaporator.
See Fig. 3
.
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tube from evaporator core fins while removing thermostatic switch. To install, reverse removal procedure. Evacuate and recharge system.
THERMOSTATIC EXPANSION VALVE
Removal & Installation
1. Discharge A/C system using approved refrigerant recovery/recycling equipment. Remove evaporator housing. See EVAPORATOR
HOUSING under REMOVAL & INSTALLATION. Remove air inlet duct. See Fig. 1 .
2. Remove insulation from sensing bulb. Disconnect thermostatic expansion valve at evaporator tube fitting and inlet tube fitting (from
receiver-drier). See Fig. 3
. Remove thermostatic expansion valve. To install, reverse removal procedure. Use new "O" rings. Evacuate
and recharge system.
A/C RELAYS
Removal & Installation
A/C relays are located in left front corner of engine compartment, near battery. Unclip relay holder from its mounting bracket. Disconnect
relay wiring. DO NOT pull on wiring connector to remove relay from holder. Remove relay from holder. To install, reverse removal procedure.
A/C-HEATER CONTROL ASSEMBLY
Removal & Installation
1. A/C control module is located above radio. Remove accessory bezel. Remove radio (if necessary) and glove box. Disconnect
recirculated/fresh air cable from door lever. See Fig. 5
. Disconnect mode select cable from door lever. See Fig. 6 .
2. Disconnect temperature control cable from door lever. See Fig. 4
. Pull control assembly away from dash, and disconnect wiring
connectors. Remove control assembly.
3. To install, reverse removal procedure. Check and adjust temperature control, recirculated/fresh air and mode cables. See
ADJUSTMENTS. Test control assembly operation.
BLOWER MOTOR
Removal & Installation
Disconnect negative battery cable. Remove A/C air outlet duct located below steering column. See Fig. 2 . Disconnect blower motor wiring.
Remove blower motor attaching screws and blower motor. Remove blower wheel attaching nut. Remove blower wheel and washer. To install,
reverse removal procedure.
BLOWER MOTOR RESISTOR
Removal & Installation
Disconnect negative battery cable. Remove air duct located below steering column. See Fig. 2 . Disconnect blower motor resistor wiring.
Remove blower resistor attaching screws and resistor. To install, reverse removal procedure.
AIR DISTRIBUTION PLENUM
Removal & Installation
1. Remove instrument panel. See INSTRUMENT PANEL under REMOVAL & INSTALLATION. Drain cooling system. Disconnect
heater hoses in engine compartment. Disconnect wiring for blower motor and blower resistor. Disengage wiring harness and antenna
lead from bracket on front of air distribution housing.
2. Loosen connector duct-to-air inlet clamp screw. Remove upper and lower mounting nuts from plenum. Disengage and remove plenum
from defroster ducts. To install, reverse removal procedure. Refill cooling system, and check for leaks.
HEATER CORE
Removal & Installation
1. Remove air distribution plenum. See AIR DISTRIBUTION PLENUM under REMOVAL & INSTALLATION. Disconnect linkage
connecting defroster doors. Remove attaching screw located near blower resistor. Turn housing around and remove attaching screw
located near blower motor opening.
2. Remove clips retaining blower housing halves. Separate blower housing halves. Remove heater core. Remove tube insert from heater
core. To install, reverse removal procedure. Test system for proper operation.
INSTRUMENT PANEL
Removal & Installation
1. Disconnect negative battery cable. Remove steering wheel, steering column covers and multifunction switch assembly. Disconnect
electrical connectors from switches on instrument panel. Remove instrument cluster hood.
2. Disconnect speedometer cable from transmission. Remove 4 instrument cluster screws. Pull instrument cluster out from instrument
panel cluster enough to disconnect wiring and speedometer cable. Remove instrument cluster.
3. Remove steering column shield. Remove shield bracket. Remove glove box. Remove fuse panel cover and 4 fuse panel screws. Pull fu se
panel out, but DO NOT remove. Remove shift lever console and mount brackets. CAUTION: DO NOT rem ove screw in front of blower resistor, or blower resistor m ounting plate will fall into air
distribution plenum . T o retrieve plate, disassem ble instrum ent panel.
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4. Remove radio and A/C-heater control assembly. See A/C-HEATER CONTROL ASSEMBLY under REMOVAL &
INSTALLATION. Disconnect cigarette lighter connector. Remove snap-in trim inserts concealing instrument panel attaching bolts.
Remove 7 instrument panel attaching bolts.
5. Remove 2 lower instrument panel-to-body bracket stud nuts. Disconnect remaining electrical connectors from instrument panel.
Remove instrument panel. To install, reverse removal procedures.
WIRING DIAGRAM

Fig. 30: Manual A/C Heater System Wiring Diagram (Festiva)

Copyr ight 2009 Mitchell Repair Information Company, LLC. All Rights Reserved.
Article GUID: A00039084
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Fig. 7: Fuse Panel Identification

Courtesy of FORD MOTOR CO.
Fuse Identification
1 - 15 Amp License Plate Light, Rear Side Marker Light, Front Parking Lights, Cluster and Tail Lights
2 - 15 Amp Horn, Brakelights, High-Mount Brakelight
3 - 15 Amp (1988-89) Safety Belt Warning, Turn & Hazard Warning Flasher Lights, Radio, Trunk Light, Ignition Key Reminder Buzzer
15 Amp (1990-93) Safety Belt Warning, Turn & Hazard Warning Flasher Lights, Ignition Key Reminder Buzzer
4 - 15 Amp Audio System, Cigarette Lighter, Remote Control Mirror
5 - 15 Amp Rear Wiper/Washer, Daytime Running Light System (Canada)
6 - 15 Amp Heater & Air Conditioner
7 - 20 Amp Heater & Air Conditioner, Cooling Fan System
8 - 10 Amp (1988-89) Interior Courtesy Lights
10 Amp (1990-93) R a d io , In t e r io r C o u r t e sy Ligh t s, Lu gga ge C o mp a r t me n t Ligh t
9 - 15 Amp (1988-89) Front Wiper/Washer
15 Amp (1990-93) Front Wiper/Washer, Shift-Lock System (ATX), Engine Control System
10 - 10 Amp Charging System, Emission Control System
11 - 10 Amp (1988-90) Safety Belt Warning, Turn & Hazard Warning Flasher Lights, Back-Up Lights, Instrument Cluster, Warning
Lights,
10 Amp (1991-93) Safety Belt Warning, Turn & Hazard Warning Flasher Lights, Back-Up Lights, Instrument Cluster, Warning Lights,
Shift-Lock System
12 - 15 Amp Rear Window Defroster
13 - Not Used (1988-89) Spare
30 Amp (1990-93) Passive Restraint System (Automatic Seat Belt)
In-Line Fuse Identification
15 Amp (1990-93) Condenser Fan Motor (A/T Models Only)
10 Amp (1990-93) A/C System (located on left side of heater case)
FUSIBLE LINK BLOCK IDENTIFICATION
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