ESP FORD FESTIVA 1991 Service Manual

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INST RUMENT PANEL
1991 ACCESSORIES & SAFET Y EQUIPMENT Ford Motor Co. Switches & Instrum ent Panels - Standard
DESCRIPTION & OPERATION
Instrument panel on Capri contains a speedometer, tachometer, fuel, water temperature, oil pressure and voltmeter gauges. A boost gauge is
incorporated into the tachometer on turbo models. Instrument panel is equipped with indicator/warning lights for charging system, air b ag,
manual shift, seat belt, turn signals, high beam and brakes. A CHECK ENGINE light, located on instrument panel, illuminates if a
computerized engine control fault occurs with engine running.
Instrument panel on Festiva contains a speedometer, fuel and water temperature gauges. Instrument panel is equipped with indicator/warning
lights for charging system, oil pressure, seat belt, rear defogger, turn signals, high beam and brakes. A CHECK ENGINE light, located on
instrument panel, illuminates if a computerized engine control fault occurs with engine running.
TROUBLE SHOOTING
FUEL GAUGE
Fuel Gauge Always Reads Empty
If fuel gauge always reads empty, check these items:
Check fuel gauge for open or damaged wires.
Check for open ground at fuel gauge sending unit.
Check for defective fuel sending unit.
Check for defective fuel gauge.
Check for defective instrument panel voltage regulator (Festiva).
Check for blown 10-amp METER fuse in fuse panel.
Check for open in Black/Yellow power feed wire from fuse panel instrument panel.
Check for fuel tank float full of fuel (sunk).
Fuel Gauge Always Reads Full
If fuel gauge always reads full, check these items:
Check for fuel gauge Yellow wire shorted to ground.
Check for defective fuel sending unit.
Check for defective fuel gauge.
Check for defective instrument panel voltage regulator (Festiva).
Fuel Gauge Inaccurate
If fuel gauge is inaccurate, check these items:
Check for faulty (loose or corroded) wire connections.
Check for defective fuel sending unit.
Check for defective instrument panel voltage regulator (Festiva).
TEMPERATURE GAUGE
Temperature Gauge Always Reads Cold
If temperature gauge always reads cold, check these items:
Check temperature gauge for open wire.
Check for defective temperature sender.
Check for defective temperature gauge.
Check for defective instrument panel voltage regulator (Festiva).
Check for blown 10-amp METER fuse in fuse panel.
Check for open in Black/Yellow power feed wire from fuse panel to instrument panel.
Temperature Gauge Always Reads Hot
CAUT ION: On m odels with Supplem ental Restraint System (SRS), observe safety precautions. T he air bag system
is powered directly from the battery and back-up power supply. Before any repairs are perform ed,
disconnect and shield battery ground cable. Disconnect the back-up power supply BEFORE servicing
ANY air bag com ponent. Use caution when working near steering colum n. Air bag could accidentally
deploy at any tim e.
NOTE:Ensure continuity exists between chassis ground and Black wire of instrum ent panel connector,
especially if fault exists in m ultiple gauge circuits. See appropriate chassis wiring diagram in the
WIRING DIAGRAMS Section.
Page 1 of 5 MITCHELL 1 ARTICLE - INSTRUMENT PANEL 1991 ACCESSORIES & SAFETY EQUIPMENT Ford Motor Co. Switches
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1990-92 ACCESSORIES & EQUIPMENT
Power Mirrors - Festiva
DESCRIPTION & OPERATION
The power outside rearview mirrors are an aerodynamic sail-mount design. See Fig. 1 . The mirror base is secured to the lower front corner of
the window frame. The screws attaching the base to the door and the wiring connector are concealed behind a trim cover which is also
attached to the window frame.
The power outside rearview mirrors are operated by a switch located to the left of the steering column just below the air discharge register. See
Fig. 1
. The switch housing actually contains two separate switch assemblies. The outer perimeter switch controls the up/down and the
inboard/outboard position of the mirrors. The center toggle switch determines which mirror is connected to the perimeter switch. When the
toggle is positioned to the left mirror, the left mirror will respond to the perimeter switch. The right mirror responds when the toggle is
positioned to the right.
Each mirror contains two electric motors -- one for tilting the mirror up or down and another for moving the mirror inboard or outboard. See
Fig. 1
. Each motor drives a gear train that includes a worm gear, a reduction gearset, and a threaded attaching lug. Rotation of the gear train
threads the attaching lug in or out of the final gear in the train. As the lug moves in the gear, it pushes or pulls the mirror into a new position.
A spring clip installed over the lug allows it to ratchet when it reaches the end of its travel.

Fig. 1: Identifying Power Rear View Mirror Components

Courtesy of FORD MOTOR CO.
COMPONENT LOCATIONS
COMPONENT LOCATIONS
ComponentLocation
Fuse PanelLeft Side Of Instrument Panel, Left Of Steering Column. See .
Ground G201Far Left Side Of Instrument Panel, Above Kick Panel. See .
Page 1 of 8 MITCHELL 1 ARTICLE - 1990-92 ACCESSORIES & EQUIPMENT Power Mirrors - Festiva
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ST EERING COLUMN SWIT CHES
1991 ACCESSORIES & SAFET Y EQUIPMENT Ford Motor Co. Steering Colum n Switches
DESCRIPTION & OPERATION
DISABLING AIR BAG SYSTEM
To disable SRS, disconnect battery cable. Unplug back-up power supply 3-way harness connector. System is now disabled. Back-up power
supply is mounted to inside of instrument panel, left of glove box opening. Glove box door must be opened past its stops and lowered toward
floor to access back-up power supply.
ACTIVATING AIR BAG SYSTEM
To activate SRS, reconnect back-up power supply connector and negative battery cable. From passenger's side of vehicle, turn ignition switch
to RUN position. System is now activated. Check AIR BAG light to ensure system is functioning properly.
TESTING
HAZARD WARNING SWITCH & TURN SIGNAL SWITCH
Capri
1. Remove steering column covers to access turn signal/hazard switch connectors. Turn ignition on. Using a 12-volt test light, ensure
battery voltage is present at Green/Red and Green/Yellow wires at turn signal/hazard switch connectors. If battery voltage is not present,
check METER and HAZARD fuses. Also check hazard and turn signal flasher units and replace as necessary.
2. If battery voltage is present at Green/Red and Green/Yellow wires, place turn signal switch in RIGHT position. Check both Green/White
wires at switch connector. Test light should flash on and off in constant cycles.
3. Place turn signal switch in LEFT position. Check both Green/Black wires at switch connector. Test light should flash on and off in
constant cycles. If turn signal/hazard switch does not function as specified, replace switch.
Festiva
1. Remove steering column covers to access turn signal/hazard switch connectors. Turn ignition on. Using a 12-volt test light, ensure
battery voltage is present at White/Black and Black/Yellow wires at hazard and turn signal switch connectors. If battery voltage is not
present, check METER and HAZARD fuses.
2. If battery voltage is present at White/Black and Black/Yellow wires, place turn signal/hazard switch in RIGHT position. Check
Green/Black wire at switch connector. Test light should flash on and off in constant cycles.
3. Place turn signal/hazard switch in LEFT position. Check Green/White wire at switch connector. Test light should flash on and off in
constant cycles. If turn signal/hazard switch does not function as specified, replace switch.
HEADLIGHT SWITCH
Capri
1. Remove instrument panel bezel to access switch connector. See HEADLIGHT SWITCH under REMOVAL & INSTALLATION.
Disconnect switch electrical connector. Measure voltage between Red and Red/White wires of headlight switch vehicle harness and
ground. If battery voltage is present, go to next step. If battery voltage is not present, check HEAD and MAIN fuses and Red and
Red/White wires between switch and fuse block.
2. Press headlight switch to first position. Using a self powered test light or ohmmeter, check continuity between switch terminals which
correspond to Red and Red/Green wires of vehicle harness connector. Continuity should not exist. If continuity exists, replace switch.
3. Press headlight switch to second position. Check continuity between switch terminals which correspond with the Red and Red/Green
wires of vehicle harness connector. Continuity should exist. If switch does not function as described, replace headlight switch. If swit ch
functions as described but headlights do not work, go to next step.
4. Remove steering column covers to access Flash-To-Pass switch connector. Using a 12-volt test light or voltmeter, place switch in
position indicated in table and check voltage between indicated wire terminals and ground. See FLASH-TO-PASS SWITCH TEST
(CAPRI) table. If switch does not function as indicated, replace switch.
FLASH-TO-PASS SWITCH TEST (CAPRI) CAUTION: On Capri m odels with Supplem ental Restraint System (SRS), observe safety precautions. T he air bag
system is powered directly from the battery and back-up power supply. Before any repairs are
perform ed, disconnect and shield battery ground cable. Disconnect the back-up power supply and wait
at least 15 m inutes BEFORE servicing ANY air bag com ponent. Use caution when working near steering
colum n. Air bag could accidentally deploy at any tim e.
NOTE:T he following disabling sequence is ONLY for com ponent replacem ent purposes.
Switch PositionWire ColorVoltage
Off
Headlights OffREDBattery
"All other wires0
Headlights OnRED, RED/GRN,
RED/BLKBattery
"All other wires0
On
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Festiva
Disconnect headlight switch. Using an ohmmeter, place switch in position indicated in table and check continuity between switch terminals
that correspond to wire colors listed. See HEADLIGHT SWITCH CONTINUITY TEST (FESTIVA) table. If switch does not function
indicated, replace switch.
HEADLIGHT SWITCH CONTINUITY TEST (FESTIVA)
IGNITION SWITCH
Capri
Remove lower steering column cover to gain access to ignition switch electrical connector. Connect a self-powered test light or ohmmeter
between blade terminals indicated in table. See IGNITION SWITCH CONTINUITY (CAPRI) table. Continuity should not exist between any
blade terminal and chassis ground in any switch position except proof circuit (162/997) in START position. See Fig. 1
.
IGNITION SWITCH CONTINUITY (CAPRI)

Fig. 1: Identifying Ignition Switch Terminals (Capri)

Courtesy of FORD MOTOR CO.
Festiva
Remove lower steering column cover to gain access to ignition switch electrical connector. Using a self-powered test light or ohmmeter, ensure
continuity exists between terminals listed in table at specified switch positions. If switch does not test as specified, replace ignition switch. See
IGNITION SWITCH CONTINUITY (FESTIVA) table. See Fig. 2
.
IGNITION SWITCH CONTINUITY (FESTIVA)
Headlights OffRED, RED/WHTBattery
"All other wires0
Headlights OnRED, RED/GRN,
RED/WHTBattery
"All other wires0
Switch PositionWire ColorContinuity
FlashRED/BLK to BLKYes
LowWHT to RED/BLKYes
HighWHT to RED/WHTYes
1RED/YEL to BLKYes
2RED/BLK to BLKYes
OffBLK to AllNo
Switch PositionContinuity Should Exist Only Between
ACC37, 297
LOCKNo Continuity
OFFNo Continuity
RUN37, 16, 687, 297
START977, 162 (Chassis Ground), 37, 32, 262
NOTE: Circuit pairs 37, 687 and 297 are connected together inside ignition switch.
TerminalPositionContinuity
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Fig. 2: Identifying Front Wiper/Washer Switch Terminals (Festiva)

Courtesy of FORD MOTOR CO.
FRONT WASHER MOTOR TEST
Remove washer fluid reservoir. Remove washer motor from reservoir. Connect fused jumper wire between washer motor terminal that
corresponds with Blue/Orange wire (Capri) or Blue wire (Festiva) and battery positive terminal. Connect other washer motor terminal to
ground. Washer motor should run smoothly. If washer motor does not run smoothly or does not run, replace motor.
REAR WIPER MOTOR TEST
Festiva
1. Place wiper in any position other than park. Disconnect wiper motor electrical connector. Using an ohmmeter, check for continuity to
ground at motor case. Continuity should exist. If continuity does not exist, repair wiper motor housing ground wire.
2. Check for continuity to ground at Blue terminal of wiper motor. Continuity should exist. If continuity does not exist, replace wiper
mo t o r.
REAR WIPER/WASHER SWITCH TEST
Festiva
Remove rear wiper/wash switch. Using a self-powered test light or an ohmmeter, ensure continuity exists between terminals listed in table at
specified switch positions. If switch does not test as specified, replace wiper/washer switch. See Fig. 3
. Also, refer to the REAR
WIPER/WASHER SWITCH CONTINUITY (FESTIVA) table.
REAR WIPER/WASHER SWITCH CONTINUITY (FESTIVA)
TerminalPositionContinuity
BLU - BLKOffNo
"OnYes
GRN/BLK - BLKOffNo
"OnYes
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resistance is not within specifications. If injector resistance is okay, check for 12 volts at each injector connector. Repair or replace
connector as necessary.
FUEL INJECTOR RESISTANCE
IDLE CONTROL SYSTEM
Idle Speed Control By-pass Air (ISC-BPA) Valve
1. Remove ISC-BPA valve from engine. Connect a hose from a hot water tap to coolant inlet nipple on ISC-BPA valve. Blow through
valve air port. Note resistance to airflow.
2. Supply hot water at 130°F (56°C) minimum to ISC-BPA valve and allow time for valve to respond. Blow through valve again. If
resistance to airflow does not increase when valve is hot, replace ISC-BPA valve.
3. Apply 12 volts to solenoid terminals. If solenoid does not click, replace ISC-BPA valve.
IGNITION SYSTEM
PICK-UP COIL
Check continuity of pick-up coil. If continuity exists, replace igniter unit. If continuity does not exist, replace pick-up coil.
TIMING CONTROL SYSTEMS
Advance Components (1.3L)
Ignition timing advance is controlled by the ECA.
Advance Components (1.6L Non-Turbo)
Ignition advance is controlled by a centrifugal advance mechanism within the distributor, and by a vacuum advance mechanism. If centrifugal
advance is not within specification, service the distributor. Replace the vacuum advance mechanism if vacuum advance is not within
specification. See IGNITION TIMING
. Also see IGNITION TIMING in ADJUSTMENTS article in the ENGINE PERFORMANCE Section.
IGNITION TIMING
Retard Components (1.6L Turbo)
Positive pressure to the vacuum advance cylinder on the distributor retards ignition timing. The ECA also retards ignition timing when it
receives a signal from a Knock Sensor (KS), Knock Control Unit (KC) and related circuitry.
1. Disconnect and plug hoses at distributor. Connect timing light and start engine. Record ignition timing. Tap intake plenum with plastic
mallet while observing ignition timing. If timing retards, knock control circuitry is okay. If timing does not retard, go to step 2).
2. Unplug KC sensor service connector near ECA. Tap intake plenum with plastic mallet while observing ignition timing. If ignition timing
retards, go to step 3). If timing does not retard, go to step 4).
3. Reconnect KC service connector. Tap intake plenum with plastic mallet while observing ignition timing. If ignition timing retards,
replace knock controller. If ignition timing does not retard, go to step 4).
4. Unplug KC service connector near ECA. Temporarily install a known good KS. Tap intake plenum with plastic mallet while observing
ignition timing. If ignition timing retards, replace KS. If ignition timing does not retard, go to step 5).
5. Turn ignition off. Connect BOB. Ensure VPWR and ground wires to KC are okay. Check all KC wiring for shorts or opens. If wiring is
okay, replace KC.
EMISSION SYSTEMS & SUB-SYSTEMS
FUEL EVAPORATION
Canister Purge Solenoid
1. Disconnect vacuum hoses from solenoid. See Fig. 1 . Blow through port "A". Ensure no air exhausts from port "B".
2. Disconnect 2-wire connector from solenoid. Connect 12 volts to one terminal and ground the other terminal of solenoid. Blow air
though port "A". Ensure air exhausts through port "B".
ApplicationOhms
1.3L & 1.6L12-16
NOTE:For basic ignition checks, see BASIC T EST ING article in the ENGINE PERFORMANCE Section.
ApplicationAuto. Trans.Man. Trans.
1.6L Non-Turbo1-3 @ 8500-4 @ 850
1.6L Turbo10-14 @ 8500-4 @ 850
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G - T EST S W/CODES
1991-92 ENGINE PERFORMANCE Ford Motor Co. Self-Diagnostics
INTRODUCTION
If no faults were found while performing BASIC TESTING , proceed with self-diagnostics. If no fault codes or only pass codes are present
after entering self-diagnostics, proceed to TESTS W/O CODES article in the ENGINE PERFORMANCE Section for diagnosis by symptom
(i.e., ROUGH IDLE, NO START, etc.).
This article uses many abbreviations for devices, signal names, and wire colors. See SELF
-DIAGNOSTICS ABBREVIATIONS table.
Abbreviations for wire colors used in individual PINPOINT TEST diagrams are as follows:
BLK - Black
BLU - Blue
BRN - Brown
GRN - Green
LT GRN - Light Green
ORG - Orange
PNK - Pink
RED - Red
WHT - White
YEL - Yellow
SELF-DIAGNOSTICS ABBREVIATIONS
SELF-DIAGNOSTIC SYSTEM
Hard Failures
Hard failures cause CHECK ENGINE light (MIL) to come on and remain on until problem is repaired. If MIL comes on and remains on (light
may flash) during vehicle operation, cause of malfunction must be determined using diagnostic (code) charts. If a sensor fails, ECA will use a
substitute value in its calculations to permit continued engine operation. In this condition (limp-in mode), vehicle will run but driveability will
not be optimum.
Intermittent Failures
Intermittent failures may cause MIL to flicker or come on and go off after intermittent defect goes away. Corresponding trouble code, however,
will be retained in ECA memory. If related defect does not reoccur within a certain time frame, related trouble code will be erased from ECA
ApplicationAbbreviation
Analog Volt/OhmmeterVOM
Barometric Pressure SensorBP
Breakout BoxBOB
Canister Purge Control SolenoidCANP
CHECK ENGINE LightMIL
Crankshaft Position SensorCPS
Cylinder Identification SensorCID
Electronic Control AssemblyECA
Electronic Engine ControlEEC
Engine Coolant Temperature SensorECT
Exhaust Gas Oxygen SensorEGO
Idle Speed ControlISC
Ignition Diagnostic MonitorIDM
Keep Alive PowerKAPWR
Key On Engine OffKOEO
Key On Engine RunningKOER
Knock ControlKC
Power & Ground ConnectionsPGC
Fuel Pressure Regulator Control SolenoidPRC
Reference Voltage & Signal ReturnVREF
Self-Test InputSTI
Self-Test OutputSTO
Signal ReturnSIGRTN
Solenoid Controlled By GroundSCG
Switch Monitor LampSML
Switch To GroundSTG
Switch To PowerSTP
Throttle Position SensorTP
Vane Airflow MeterVAF
Vane Air Temperature SensorVAT
Vehicle PowerVPWR
Vehicle Speed SensorVSS
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Fig. 6: Identifying KC Circuit & Connectors

1. Disconnect and plug vacuum hose at distributor. Connect timing light. Start engine. Unplug knock control service connector, located
near ECA. If timing retards, service knock sensor and/or knock sensor wiring. If timing does not retard, go to next step.
2. Determine and record ignition timing setting. Tap intake plenum with plastic mallet. If timing does not retard, go to step 4). If t imin g
retards, go to next step.
3. Reconnect knock control service connector, located near ECA. Determine and record ignition timing setting. Tap intake plenum with
plastic mallet. If timing does not retard, knock control unit is okay; go to next step. If timing retards, replace knock control unit.
4. Turn ignition off. Unplug knock control service connector, located near ECA. Install a known good knock sensor. Start engine. Tap
intake plenum with plastic mallet. If timing retards, replace knock sensor. If timing does not retard, go to next step.
5. Check VPWR and GND (Yellow/Green and Black/Yellow wires respectively) to knock control unit for shorts or open circuits. Service
wires as necessary. If wires are okay, replace knock control unit.
PINPOINT TEST VSS - VEHICLE SPEED SENSOR

Fig. 7: Identifying VSS Circuit & Connectors

VSS CIRCUIT PIN IDENTIFICATION
1.Install 4EAT Tester Leave 4EAT module disconnected. Disconnect speedometer cable at transaxle. Measure resistance between BOB
VSS and GND test pins. Rotate speedometer cable. If resistance drops to less than 5 ohms 4 times for each revolution of speedometer
cable, VSS is okay. Return to QUICK TESTS if sent here from there; otherwise, replace 4EAT module. If resistance does not drop as
NOTE:Enter this test only when Code 06 is displayed during QUICK T EST S procedure or when directed here
from another PINPOINT TEST.
Circuit4EAT PinWire Color
GND1JBLK
VSS1PGRN/RED
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specified, go to next step.
2. Unplug VSS connector at instrument cluster. Measure resistance between VSS and GND terminals on instrument cluster. Rotate
speedometer cable. If resistance drops to less than 5 ohms 4 times for each revolution of speedometer cable, repair VSS signal wire to
4EAT. If resistance does not drop as specified, replace speedometer assembly.
PINPOINT TEST VAF - VANE AIRFLOW METER

Fig. 8: Identifying VAF Meter Circuits

VAF CIRCUIT PIN IDENTIFICATION
1.3L
1. Turn ignition off. Install BOB. Turn on ignition. Measure voltage between VAF and ground pins while moving vane in VAF meter.
Voltage should vary smoothly between .5-1.5 volts with door open, and 4.5-5.0 with door closed. If voltage is as specified, VAF met er
is okay; return to QUICK TESTS if sent here from there. If not sent here from QUICK TESTS, replace ECA. If voltage is not as
specified, go to next step.
2. Remove connector from VAF meter. Using jumper wires, connect VREF and ground terminals on VAF connector to corresponding
terminals on VAF meter. Turn ignition on. Measure voltage between VAF terminal on VAF meter and ground terminal while moving
vane in VAF meter. Voltage should vary smoothly between .5-1.5 volts with door open, and 4.5-5.0 with door closed. If voltage is
correct, repair VAF circuit between ECA and VAF meter. If voltage is not as specified, go to next step.
3. Turn ignition off. Unplug VAF meter connector. Turn ignition on. Measure voltage between VREF and ground wires. If voltage is 4.5-
5.5 volts, replace VAF meter. If voltage is not 4.5-5.5 volts, go to PINPOINT TEST VREF.
1.6L
1. Turn ignition off. Install BOB. Turn ignition on. Measure voltage between VAF and SIGRTN pins while moving vane in VAF meter.
Voltage should be as specified in VAF METER VOLTAGE table. If voltage is not as specified, go to step 3). If voltage is as specified, go
to next step.
2. Measure voltage between VMREF and SIGRTN test pins. If voltage is 7-9 volts, circuit is okay; return to QUICK TESTS if sent here
from there. If not sent here from QUICK TESTS, replace ECA. If voltage is not as specified, repair VMREF wire to VAF.
3. Unplug connector from VAF meter. Using jumper wires, connect VPWR, VMREF, and SIGRTN terminals on VAF connector to
corresponding terminals on VAF meter. Leave VAF wire disconnected. Measure voltage between VAF and SIGRTN pins on harness NOTE:Enter this test only when a Code 08 is displayed during QUICK TESTS procedure, or when directed here
from another PINPOINT T EST . T o avoid unnecessary diagnostic tim e, check for unm etered air leaks
between VAF m eter and throttle body. T his test is intended to diagnose only VAF and VREF circuits.
CircuitECA PinBOB PinWire Color
1.3L
GND2A45BLK
VAF2O25WHT
VREF2D46, 49BLK
1.6L
SIGRTN2C46BLK/YEL
VAF2E43LT GRN/BLK
VMREF2B18LT GRN/RED
VPWR3I37YEL/GRN
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connector while moving vane in VAF meter. Voltage should be as specified in VAF METER VOLTAGE table. If voltage is okay,
repair VAF wire to ECA. If voltage is not okay, go to next step.
VAF METER VOLTAGE
4. Unplug connector from VAF. Using jumper wires, connect VPWR and SIGRTN terminals on VAF connector to corresponding terminals
on VAF meter. Leave VAF and VMREF wires disconnected. Measure voltage between VAF terminal at VAF meter, and SIGRTN pin at
harness connector while moving vane in VAF meter. Voltage should be as specified in VAF METER VOLTAGE
table. If voltage is
okay, repair VMREF wire to ECA. If voltage is not okay, go to next step.
5. Unplug connector from VAF meter. Turn ignition on. Measure voltage between SIGRTN and VPWR wire. If voltage is more than 10
volts, replace VAF meter. If voltage is not more than 10 volts, go to next step.
6. Unplug VAF meter connector. Turn ignition on. Measure voltage between VAF meter VPWR wire and ground. If voltage is more than
10 volts, repair VAF wire to ECA. If voltage is not more than 10 volts, go to PINPOINT TEST VPWR.
PINPOINT TEST ECT - ENGINE COOLANT TEMPERATURE SENSOR

Fig. 9: Identifying ECT Sensor Circuits

ECT CIRCUIT PIN IDENTIFICATION
1.3L
1. Turn ignition off. Install BOB. Leave ECA disconnected. Unplug ECT connector. Check for continuity between ECT test pin and ECT
terminal (Red/Blue wire) on ECT harness connector. If continuity does not exist, repair ECT wire between ECA and ECT sensor. If
continuity exists, go to next step.
2. Unplug ECT sensor. Check for continuity between Black wire at ECT sensor and ground. If continuity does not exist, repair Black wire
between ECT sensor and ground. If continuity exists, go to next step.
3. Reconnect ECA. Measure resistance between BOB ECT test pin and ground pin. If resistance is 500-1000 ohms, replace ECA. If
resistance is not 500-1000 ohms, replace ECT sensor.
1.6L
1. Turn ignition off. Install BOB. Leave ECA disconnected. Unplug ECT connector. Check for continuity between ECT test pin and ECT
terminal (Blue/Red wire) on ECT harness connector. If continuity does not exist, repair ECT wire between ECA and ECT sensor. If
Door PositionVolts
1/8 Open3.24
1/4 Open5.60
3/8 Open5.62
1/2 Open5.83
5/8 Open6.02
3/4 Open6.57
7/8 Open7.46
Full Open7.87
NOTE:Enter this test only when a Code 09 is displayed during QUICK T EST S procedure or when directed here
from another PINPOINT T EST . T o prevent unnecessary diagnosis, inspect coolant level, oil level,
cooling fan, therm ostat, and airflow to radiator before testing.
CircuitECA PinBOB PinWire Color
1.3L
ECT2Q7RED/BLU
GND(1) (1) BLK
1.6L
ECT2I7BLU/RED
SIGRTN2C46BLU/YEL
(1)Not specified.
Page 10 of 20 MITCHELL 1 ARTICLE - G - TESTS W/CODES 1991-92 ENGINE PERFORMANCE Ford Motor Co. Self-Diagnostics
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