check engine light FORD FESTIVA 1991 User Guide

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D - ADJUSTMENTS
1991 ENGINE PERFORMANCE Ford/Mercury - On-Vehicle Adjustm ents
ADJUSTMENTS
ENGINE MECHANICAL
Before beginning any on-vehicle adjustments to fuel or ignition systems, ensure engine mechanical condition is okay.
VALVE CLEARANCE
IGNITION TIMING
CAPRI
1. Place automatic transmission in Park or manual transmission in Neutral. Disconnect and plug hoses attached to vacuum diaphragm
assembly on distributor. Connect tachometer and timing light. Turn off all electrical loads.
2. Start engine, and warm it to operating temperature. Ensure idle speed is set to specification, adjusting if necessary. See IDLE SPEED &
MIXTURE . Determine initial timing. See IGNITION TIMING table. If base timing is not correct, loosen distributor mounting bolts
and rotate distributor until marks align. Tighten bolts to 14-18 ft. lbs. (19-25 N.m).
3. Increase engine RPM while observing timing light. Verify ignition timing advances. For Turbo models, go to step 5). For non-Turbo
models, continue with step 4).
4. On non-Turbo models, apply 16 in. Hg vacuum to chamber "A". Verify timing advances by 26-30 degrees. Remove vacuum source from
chamber "A". Apply 8 in. Hg vacuum to chamber "B" while observing timing. Verify timing advances by 3-7 degrees. Stop engine, and
remove test equipment.
5. On Turbo models, apply 20 in. Hg vacuum to advance diaphragm. Verify timing advances by 13-17 degrees. Disconnect vacuum source.
Apply 8 psi (.6 kg/cm
2 ) pressure to advance diaphragm. Verify timing retards by 3-7 degrees. Stop engine, and remove test equipment.
FESTIVA
1. Place manual transmission in Neutral or automatic transmission in Park. Turn all accessories off. Locate one-wire STI (Black) connector
near master cylinder. Using a jumper wire, connect STI terminal to ground. See Fig. 1
. Connect timing light and tachometer.

Fig. 1: Locating Self
-Test Input (STI) Connector
Courtesy of FORD MOTOR CO.
2. Start engine, and warm to operating temperature. Ensure idle speed is set to specification, adjusting if necessary. See IDLE SPEED &
MIXTURE .
3. Check initial timing. White timing mark should align with white mark on crankshaft pulley. If marks do not align, loosen distributor
mounting bolts and rotate distributor until marks align. Tighten bolts to 14-18 ft. lbs. (19-25 N.m).
4. Remove jumper wire. Increase engine RPM, and verify ignition timing advances beyond initial setting. Stop engine, and remove test
equipment.
IGNITION TIMING NOTE:All m odels are equipped with hydraulic lash adjusters. No adjustm ents are required.
Page 1 of 3 MITCHELL 1 ARTICLE - D - ADJUSTMENTS 1991 ENGINE PERFORMANCE Ford/Mercury - On-Vehicle Adjustments
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ABBREVIATIONS
ACL
Air Cleaner (Thermostatic Air Cleaner)
AIS
Air Injection System
AIS-ACV
AIS Air Control Valve
AIS-AMV
AIS Air Management Valve
AIS-ASS
AIS Air Switching Solenoid
AIS-ASV
AIS Air Switching Valve
AIS-BPV
AIS By-Pass Valve
AIS-CKV
AIS Check Valve
AIS-CV
AIS Combination Valve
AIS-DV
AIS Diverter Valve
AIS-RV
AIS Relief Valve
AIS-SOL
AIS Solenoid
AIS-SV
AIS Solenoid Valve
CS, EGR-PS, SPK-CC
(1)For quick reference, major emission control systems and devices are listed in bold type; components and other related devices are
listed in light type.
(2)California only.
(3)A/T only.
(4)Federal only.
(5)M/T only.
(6)2.8L & California 2.3L.
(7)Except Federal models.
(8)2.0L only.
(9)2.3L California only.
(10)M/T only.
(11)California with M/T.
(12)Some models.
(13)Federal with M/T.
(14)M/T models with engine family VBT.
(15)Electronically controlled.
Page 4 of 9 MITCHELL 1 ARTICLE - EMISSION CONTROL APPLICATIONS Emission Applications - Ford Motor Co. - Imports (1968-
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J - PIN VOLT AGE CHART S
1991 ENGINE PERFORMANCE Ford/Mercury Pin Voltage Charts
INTRODUCTION
Pin voltage charts are supplied to reduce diagnostic time. Checking pin voltages at the Electronic Control Assembly (ECA) determin es
whether it is receiving and transmitting proper voltage signals. Charts may also help determine if ECA wiring harness is shorted or opened.

Fig. 1: Identifying ECA Connector Terminals (Festiva)

Courtesy of FORD MOTOR CO.

Fig. 2: Identifying ECA Connector Terminals (Capri)

Courtesy of FORD MOTOR CO.
NOTE:Unless stated otherwise in testing procedures, perform all voltage tests using a Digital Volt-Ohm m eter
(DVOM) with a m inim um 10-m egohm input im pedance. Voltage readings m ay vary slightly due to
battery condition or charging rate.
NOTE:For additional pin voltage inform ation, see appropriate trouble code inform ation in G - T EST S W/
CODES article in the ENGINE PERFORMANCE Section.
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Connect BOB. Remove dust cover from BP sensor, located on passenger side cowl. Turn ignition on. Connect vacuum pump to BP sensor.
Measure voltage between pins BP and SIGRTN on BOB while applying vacuum to BP sensor. See BAROMETRIC PRESSURE SENSOR
OUTPUT VOLTAGE . Replace BP sensor if voltage is not as specified.
BAROMETRIC PRESSURE SENSOR OUTPUT VOLTAGE
BRAKE ON-OFF (BOO) SWITCH
Unplug connector from BOO switch at brake pedal. Connect ohmmeter to switch terminals. With pedal released, ohmmeter should indicate no
continuity. Ohmmeter should indicate continuity with pedal depressed.
CLUTCH ENGAGE SWITCH (CES)
Unplug connector from CES switch at clutch pedal. Connect ohmmeter to switch terminals. With pedal released, ohmmeter should indicate
continuity. Ohmmeter should indicate no continuity with pedal depressed.
CRANKSHAFT POSITION SENSOR (CPS) (1.3L)
Unplug 3-wire connector from distributor. Measure resistance between CPS terminal on distributor (Yellow/Blue wire) and ground. Replace
CPS if resistance is not 210-250 ohms.
CYLINDER IDENTIFICATION (CID) SENSOR (1.6L)
Turn ignition off. Connect BOB, leaving ECA connected. Turn ignition on, but DO NOT start engine. Measure voltage at BOB pin No. 34
(Yellow wire). Volt- meter should indicate less than one volt or more than 10 volts. Start engine and run at idle. Voltmeter should indicate 3-
5 volts. Replace CID sensor if voltage is not as specified.
ENGINE COOLANT TEMPERATURE (ECT) SENSOR
1. Remove ECT sensor. ECT sensor is threaded into top of lower intake manifold on 1.3L, and on underside of intake manifold on 1.6L.
Place ECT sensor and thermometer into container of coolant.
2. Connect ohmmeter to coolant temperature sensor terminals. Cool or heat container. Note resistance at specified temperatures. See
ENGINE COOLANT TEMPERATURE SENSOR RESISTANCE
. Replace ECT sensor if resistance is not within specification.
ENGINE COOLANT TEMPERATURE SENSOR RESISTANCE
EXHAUST GAS OXYGEN (EGO) SENSOR
With engine at normal operating temperature, unplug connector from EGO in exhaust manifold. Measure voltage between EGO sensor
terminal and ground. Voltage should increase with increasing engine speed and decrease with decreasing engine speed. Voltage at idle should
fluctuate within a range of .2-.8 volt.
IDLE SW ITCH (1.6L)
Unplug connector from throttle position sensor on throttle body. Connect ohmmeter to switch terminals IDL and ground (Green/Orange and
Blue/Yellow wires on mating connector). Resistance must be less than 5 ohms with throttle in idle position, and more than 10,000 ohms with
throttle pedal depressed.
KNOCK SENSOR (1.6L TURBO)
Disconnect vacuum hose at distributor. Connect timing light. Start engine and record ignition timing. Tap intake plenum with a plastic mallet.
Knock sensor is okay if timing retards. If timing does not retard, check associated circuitry and components. See TIMING CONTROL
SYSTEMS under IGNITION SYSTEM.
NEUTRAL GEAR SWITCH (M/T)
1. Unplug connector near transmission. Place transmission in Neutral. Resistance across switch should be infinite.
2. Place transmission in any other gear. Resistance across switch should be zero ohms. If necessary, replace switch.
Vacuum In. Hg.(1) Voltage
03.84
53.36
102.66
151.93
201.26
25.58
(1)Voltage may vary by plus or minus 15 percent.
Temperature °F (°C)Ohms
-4 (-20)14,600-17,800
68 (20)2200-2700
104 (40)1000-1300
140 (60)500-650
176 (80)290-350
NOTE:A steady voltage higher than .55 volt indicates a continuously rich condition. A steady voltage lower
than .55 volt indicates a continuously lean condition.
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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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memory. Intermittent failures may be caused by a sensor, connector, or wiring. See INTERMITTENTS in TESTS W/O CODES article in the
ENGINE PERFORMANCE Section.
VISUAL CHECK & VEHICLE PREPARATION
Before connecting any equipment to diagnose EEC system, perform following preparatory procedures:
Verify condition of air cleaner and air ducts.
Check all vacuum hoses for leaks, restrictions, or improper routing.
Check EEC system wiring harness electrical connections for corrosion, bent or broken pins, loose wires or terminals, or improper
routing.
Check ECA, sensors, and actuators for physical damage.
Check engine oil and coolant level.
Perform all necessary safety precautions to prevent personal injury or vehicle damage.
Set parking brake. Place shift lever in Park for automatic transmissions, or Neutral for manual transmissions. DO NOT move shift lever
during test unless specifically directed.
Turn off all lights and accessories. Ensure vehicle doors are closed when measuring voltage or resistance.
Start engine. Run at idle until upper radiator hose is hot and pressurized and engine is off fast idle. Check for leaks around exhaust
manifold, exhaust gas oxygen sensor, and vacuum hose connections.
Turn ignition off. Service items as required. Go to EQUIPMENT HOOK-UP .
EQUIPMENT HOOK-UP
VOM
1. Turn ignition off. Connect a jumper wire from STI connector to ground. Refer to SELF-TEST CONNECTOR LOCATION and
SELF
-TEST CONNECTOR WIRE COLORS tables. See Fig. 1 .
2. Connect VOM between STO terminal and engine ground. Set VOM to measure 0-20 volts DC.
CHECK ENGINE Light (MIL)
Connect a jumper wire between STI connector and ground.
SUPER STAR II Tester
Turn ignition off. Connect adapter cable leads to diagnostic tester. Connect service adapter cables to vehicle self-test connectors. Ground
adapter cable.
SELF-TEST CONNECTOR LOCATION
SELF-TEST CONNECTOR WIRE COLORS

Fig. 1: Self
-Test Connector Terminal ID
Courtesy of FORD MOTOR CO.
RETRIEVING CODES
Reading Service Codes
ApplicationLocation
1.3LLeft Rear Corner Of Engine Compartment
1.6LRight Rear Corner Of Engine Compartment
CircuitWire Color
1.3L
SMLBlue/Green
STIYellow/Green
STOYellow/White
1.6L
SMLBlack/Blue
STIYellow
STOGreen/Black
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CLEARING CODES
Clearing Codes Procedure
Disconnect negative battery cable. Press brake pedal for 5-10 seconds. Turn off VOM or Super Star II tester. Reconnect battery.
ECA LOCATION
ECA is located on center console behind kick panel on Capri, and under instrument panel on driver side of Festiva.
QUICK TESTS
KEY ON, ENGINE OFF (KOEO) SELF-TEST
KOEO
1. This is a test of electronic engine control system, conducted with power (voltage) applied and engine not running. Activate self-test, and
record all codes displayed.
2. Erase codes, and repeat self-test. Diagnose only codes occurring during repeat self-test. See TROUBLE CODE DEFINITION
table. If
no codes are present, proceed to KEY ON, ENGINE RUNNING (KOER) SELF
-TEST .
KEY ON, ENGINE RUNNING (KOER) SELF-TEST
KOER
1. Deactivate self-test. Start and run engine at 2000 RPM for 2 minutes to warm up EGO sensor. Turn off engine and wait 10 seconds.
2. Restart engine, and activate self-test. Record all service codes displayed. See TROUBLE CODE DEFINITION
table. If no codes are
present, proceed to SWITCH MONITOR TEST
.
SWITCH MONITOR TEST
This test procedure checks input signals received by ECA from individual switches. Use following procedure to perform switch monitor test:
Turn engine off and allow it to cool.
Ensure all accessories are turned off.
Deactivate self-test.
Ensure transmission is in Neutral or Park.
Turn ignition on.
SUPER STAR II Tester
Connect Super Star II tester adapter cable. Turn on tester. Latch center button. Operate each switch listed in SWITCH MONITOR TEST
table. Note output of LED on adapter cable as each switch operates. Record test results.
VOM
1. Ground STI connector. Connect VOM positive lead to SML terminal on self-test connector. Connect negative lead to ground. See Fig.
1 .
2. Operate each switch listed in SWITCH MONITOR TEST
table. Note output on VOM as each switch is operated. Go to specified
PINPOINT TEST if any switch does not meet specification.
SWITCH MONITOR TEST
(1)Festiva only.
(2)Capri only.
NOTE:DO NOT m ove throttle during KOEO self-test.
NOTE:It is necessary to clear codes in m em ory before perform ing this test. DO NOT m ove throttle during test.
NOTE:All switches m ust be tested individually. Allowing a switch to rem ain on while testing another will lead
to false test results.
NOTE:DO NOT m ove throttle, clutch, or transm ission lever unless so directed.
SwitchVOM Indication/Condition(1) Pinpoint Test
A/C SwitchLess Than 1.5 Volts; A/C & Blower Switch OnSTG
Blower Motor SwitchLess Than 1.5 Volts; Switch Set To "2" Or HigherSTG
Brake On/Off SwitchLess Than 1.5 Volts; Brake Pedal Partially
PressedSTP
Clutch Engage/Neutral Gear Switch (2) Less Than 1.5 Volts; In Gear, Clutch ReleasedSTG
Coolant Temperature SwitchLess Than 1.5 Volts; Cooling Fan OnSTP
Defrost SwitchLess Than 1.5 Volts; Defrost Switch OnSTP
Headlight SwitchLess Than 1.5 Volts; Headlight Switch OnSTP
Id l e Swit chLess Than 1.5 Volts; Accelerator Pedal PressedSTG
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WIGGLE TEST
Checking Circuitry
1. Visually inspect suspected sensor, switch, or solenoid. Enter WIGGLE TEST if using Super Star II tester. If using VOM, connect it to
STO terminal on self-test connector, and ground STI self-test connector terminal. Lightly tap sensor, switch, or solenoid.
2. Push and pull on suspected sensor, switch, or solenoid connector, but DO NOT unplug it. Test and wiggle harness vigorously, working
in small sections, from suspected device toward dash panel, and from dash panel to ECA.
3. If VOM or Super Star II tester does not display a positive indication of an intermittent defect, carefully disconnect suspected device.
Remove terminals from connector.
4. Inspect terminals at both ends for corrosion, bad crimps, or improperly seated terminals. Reconnect after inspection. Unplug harness
fro m E CA.
5. Inspect ECA and harness connector terminals for corrosion, bad crimps, or improperly seated terminals. If VOM does not indicate any
intermittent defect, reconnect wiring and erase codes.
PINPOINT TESTS
HOW TO USE PINPOINT TESTS
1. DO NOT perform any PINPOINT TEST unless directed by a QUICK TESTS procedure. Ensure all non-EEC related defects are
corrected. Follow each test step in order until defect is found. DO NOT replace any part unless so directed. When more than one service
code exists, start with first code displayed.
2. PINPOINT TESTS require ensuring electrical circuits are okay before replacing sensors or any other components. Always test circuits
for continuity between sensor and ECA. Test all circuits for shorts to power, opens, or shorts to ground. VREF and VPWR circuits
should be tested with KOEO or as specified in PINPOINT TESTS.
3. DO NOT measure voltage or resistance at ECA, or connect any test light unless specified in testing procedure. DO NOT pierce wiring.
Isolate both ends of a circuit and turn key off whenever checking for shorts or continuity, unless otherwise specified.
4. Disconnect solenoids and switches before checking circuit continuity or energizing solenoids.
5. An open is defined as any resistance greater than 10,000 ohms, unless otherwise specified.
6. To help diagnose circuits to ECA, turn ignition off and disconnect ECA harness. Connect BOB between ECA and ECA harness to
perform circuit and pinpoint tests.
PINPOINT TEST IDM - IGNITION DIAGNOSTIC MONITOR

Fig. 3: Identifying IDM Circuit & Connector

IDM CIRCUIT PIN IDENTIFICATION
Manual Lever Position SwitchLess Than 1.5 Volts; Transaxle In Park Or NeutralSTP
Wide Open Throttle SwitchLess Than 1.5 Volts; Accelerator Pedal Fully
PressedSTG
(1)Proceed to PINPOINT TEST indicated if Super Star II tester/VOM indication is incorrect.
(2)Not applicable to vehicles with A/T.
NOTE:Following tests and illustrations are courtesy of Ford Motor Co. Com plete EEC system wiring diagram s
m ay be found in WIRING DIAGRAMS article in the ENGINE PERFORMANCE Section.
NOTE:Check all wiring, harnesses, connectors, and com ponents for dam age, overheating, shorting, or
looseness. If any defect is found, repair as necessary before proceeding to any PINPOINT T EST .
NOTE:Enter this test only when Code 01 is displayed during QUICK T EST S procedure or when directed here
from another PINPOINT TEST.
CircuitECA PinBOB PinWire Color
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1.3L
1. Connect spark tester between coil secondary wire and ground. Crank engine several times, leaving ignition on between cranking periods.
If continuous sparks jump tester gap, go to next step. If continuous sparks do not jump tester gap, go to step 3).
2. With ignition off, connect BOB, leaving ECA disconnected. Connect test light between test pins IDM and VPWR. Crank engine several
times. If test light flashes each time engine cranks, IDM circuit is okay. Return to QUICK TESTS if directed here from there. If test light
does not flash, repair IDM wire between ECA and coil.
3. Unplug connector from ignition coil. Connect test light between coil IDM wire and PWR wire. Crank engine several times, leaving
ignition on between cranking periods. If test light flashes continuously, go to next step. If test light does not flash continuously, go to
step 6).
4. Turn ignition on. Measure voltage between coil harness PWR wire and ground. If voltage is greater than 10 volts, replace coil. If voltage
is less than 10 volts, repair wire between ignition switch and coil.
5. Connect test light between PWR and ground terminals at coil harness connector. Turn ignition on. If test light glows, replace coil. If test
light does not glow, repair ground wire to coil.
6. Unplug connector from ignition module. Connect jumper wire between SPOUT wire on ignition module harness connector and mating
terminal on ignition module. Connect another jumper wire between ignition module GND wire and mating connector. Leave IDM wire
disconnected. Connect test light between IDM terminal on ignition module and PWR wire. Crank engine several times, leaving ignition
on between cranking periods. If test light flashes each time engine cranks, repair wire between ignition module IDM wire and coil . If t est
light does not flash, go to next step.
7. Turn ignition off. Unplug ignition module connector. Turn ignition on. Measure voltage between ignition module PWR wire and ground.
Turn ignition on. If voltage is not more than 10 volts, repair PWR wire from ignition switch. If voltage is more than 10 volts, go t o n e xt
step.
8. Turn ignition off. Unplug ignition module connector. Turn ignition on. Connect test light between ignition coil PWR wire and ignition
module GND wire. Turn ignition on. If test light glows, go to step 10). If test light does not glow, go to next step.
9. Turn ignition off. Unplug ignition module connector. Connect test light between ignition coil PWR wire and ignition module SPOUT
wire. Crank engine. If test light flashes, check ignition module SPOUT wire for short to ground; if no short exists, replace ignition
module. If test light does not flash, go to next step.
10. Turn ignition off. Unplug ignition module connector. Install BOB, leaving ECA disconnected. Check SPOUT wire for continuity
between BOB test pin and ignition module. If continuity exists, check SPOUT wire for shorts to any other wire. If no short exists,
replace ECA. If continuity does not exist, repair SPOUT wire to ECA.
1.6L
1. Connect spark tester between coil secondary wire and ground. Crank engine several times, leaving ignition on between cranking periods.
If continuous sparks do not jump tester gap, go to step 3). If continuous sparks jump tester gap, go to next step.
2. Turn ignition off. Connect BOB. Leave ECA disconnected. Connect test light between test BOB pins IDM and VPWR. Crank engine
several times. If test light flashes each time engine cranks, IDM circuit is okay. Return to QUICK TESTS if directed here from there. If
test light does not flash, repair IDM wire between ECA and coil.
3. Unplug connector from ignition coil. Connect test light between coil IDM wire and PWR wire. Crank engine several times, leaving
ignition on between cranking periods. If test light does not flash continuously, go to step 6). If test light flashes continuously, go to next
step.
4. Turn ignition on. Measure voltage between coil harness PWR wire and ground. If voltage is greater than 10 volts, replace coil. If voltage
is less than 10 volts, repair wire between ignition switch and coil.
5. Connect test light between PWR and ground terminals at coil harness connector. Turn ignition on. If test light glows, replace coil. If test
light does not glow, repair ground wire to coil.
6. Unplug connector from ignition module. Connect a jumper wire between PWR wire on ignition module harness connector and mating
terminal on ignition module. Leave IDM wire disconnected. Connect test light between IDM terminal on ignition module and PWR
wire. Crank engine several times, leaving ignition on between cranking periods. If test light flashes each time engine cranks, repair wire
between ignition module IDM wire and coil. If test light does not flash. go to next step.
7. Unplug connector from ignition module. Measure voltage between ignition module PWR wire and ground. If voltage is not higher than
10 volts, repair PWR wire from ignition switch. If voltage is higher than 10 volts, go to next step.
8. Turn ignition off. Unplug ignition module connector. Turn ignition on. Connect test light between ignition module PWR wire and
ignition module GND wire. Turn ignition on. If test light glows, replace ignition module. If test light does not glow, repair ignition
module ground wire.
PINPOINT TEST CPS - CRANKSHAFT POSITION SENSOR
1.3L
GND2A39, 40, 44, 60BLK
IDM(1) (1) YEL/GRN
PWR(1) (1) BLK/WHT
SPOUT1G36BLU/ORG
1.6L
IDM1M6YEL/BLU
PWR**********BLK/WHT
(1)ECA and BOB pins not specified.
NOTE:Enter this test only when Code 02 is displayed during QUICK T EST S procedure or when directed here
from another PINPOINT TEST.
Page 6 of 20 MITCHELL 1 ARTICLE - G - TESTS W/CODES 1991-92 ENGINE PERFORMANCE Ford Motor Co. Self-Diagnostics
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