Engine Controls - Tests W/o Codes Mercury Topaz II

INTRODUCTION

Before attempting to diagnose driveability symptoms or intermittent faults that cause driveability problems, ensure that the steps in the BASIC TESTING and TESTS W/CODES articles have been performed. Use this article to diagnose driveability problems that exist when a hard fault code is not present.

A symptom can be defined as an indication or characteristic of a condition which causes a driveability complaint. Often a customer's complaint of a driveability symptom will be any condition which is different from when the car was purchased or new. Always understand the customer's perception of the symptom. Symptom checks are intended to direct the technician to malfunctioning component or system so that further diagnosis may be performed. A symptom should lead to further testing of specific components or systems, or verification of adjustment specifications.

An intermittent driveability problem can be defined as one that comes and goes during any particular driving cycle. This type of problem includes electrical circuits or component problems that may or may not set a soft code in the ECA memory. This means the problem may turn the CHECK ENGINE or SERVICE ENGINE SOON light on or cause it to flicker without setting a code in memory. The intermittent problem could occur in a circuit not monitored by diagnostics. The key word in this definition is INTERMITTENT. If the problem is happening all the time, treat it as a symptom, not as an intermittent.

Note. It is also possible that certain driveability concerns have been rectified by the manufacturer through revised calibration of the Electronic Control Assembly (ECA) computer control unit. Check with manufacturer for latest information on updated calibration information and control units.

Note. For verifying adjustment specifications, refer to the appropriate ADJUSTMENTS or SPECIFICATIONS article in this section.

DRIVEABILITY SYMPTOM CHECK PROCEDURES

Symptom checks cannot be used properly unless the problem or driveability characteristic actually happens while the vehicle is being tested. To reduce diagnostic time, ensure steps in the BASIC TESTING and TESTS W/CODES articles have been performed before attempting to diagnose a symptom.

DIAGNOSTIC ROUTINES are indexed for your convenience. For the menu screen, the titles have been shortened to ROUTINE. This allows for more of the information to be displayed on the menu. They should be used to identify systems and components that should be checked to identify a fault. Perform the check or adjustment as indicated in the appropriate ROUTINE chart. a reference may be given to direct you to another test procedure or to a specific CIRCUIT TEST in the TESTS W/CODES article. This will provide additional information for checking a component or circuit.

On vehicles equipped with EEC-IV systems, charts are provided to direct the technician to CIRCUIT TESTS in the TESTS W/CODES article. This is the circuit or component most likely to be the cause of the applicable driveability symptom. These charts should only be used in conjunction with the DIAGNOSTIC ROUTINES.

SYMPTOM-TO-ROUTINE MENU

SYMPTOM-TO-DIAGNOSTIC ROUTINE MENU

INTERMITTENT PROBLEM DIAGNOSIS

Use intermittent test procedures to locate intermittent driveability problems that do not occur when the vehicle is being tested. These problems may cause a noticeable driveability problem or cause the CHECK ENGINE or SERVICE ENGINE SOON warning light to illuminate on some vehicles.

Intermittent fault testing requires the duplication of circuit or component failure in order to identify the fault. These procedures may lead to the computer recording a fault code (on some systems) which may help in diagnosis.

If problem vehicle does not produce fault codes, it will be necessary to monitor voltage or resistance values using a Digital Volt Ohmmeter (DVOM) while attempting to reproduce conditions that will create an intermittent fault. A change in status on the DVOM will indicate a fault has been located.

When using a DVOM or Scan tool to pinpoint faults, monitor voltage reading with ignition on or vehicle running. A change in status on the voltmeter while performing intermittent test procedures will indicate area of fault.

When using an ohmmeter to detect problems in the circuit, monitor circuit resistance (ohms) with ignition off or with battery disconnected. A change in ohmmeter reading while performing test procedures will indicate area of fault.

INTERMITTENT SIMULATION

To reproduce the conditions that create an intermittent fault so it may be identified during testing, some of the following methods may be used

1. Applying light vibration to components.
2. Heating a component.
3. Wiggling or bending a wiring harness.
4. Applying humidity to a component.
5. Removing or applying a vacuum supply source.

Monitor circuit/component voltage or resistance while attempting to simulate intermittent. If vehicle is running, monitor for self-diagnostic codes. See TESTS W/CODES article. Use the results of these tests to identify a faulty component or an area that should be closely checked for the problem.

Note. For additional information on connecting test equipment and operating Continuous Monitor Mode test procedures, see TESTS W/CODES article.

CONTINUOUS MONITOR MODE (WIGGLE TEST)

This test allows a technician to attempt to re-create an intermittent fault while monitoring the system. This mode, also called the "wiggle test", may be used in both Key On Engine Off (KOEO) and Key On Engine Running (KOER) Self-Test modes. The CIRCUIT TESTS in TESTS W/CODES article specify the use of this procedure to identify intermittent faults in specific circuits or components.

KOEO WIGGLE TEST PROCEDURE

Connect test equipment. Turn ignition on and activate self-test with jumper lead or diagnostic tester. Wait 10 seconds, deactivate and then reactivate self-test. Wiggle test mode has been achieved. Tap, move and wiggle the suspected sensor and/or harness area. If a fault is detected, a code may be stored in memory and indicated at the diagnostic tester or Scan tool. Record code and perform CIRCUIT TEST indicated in CONTINUOUS MEMORY CODES chart. See TESTS W/CODES article.

KOER WIGGLE TEST PROCEDURE

Connect test equipment. Turn ignition off and wait 10 seconds. Start engine. Activate self-test with jumper lead or diagnostic tester. Wait 10 seconds, deactivate and then reactivate self-test. DO NOT turn engine off. Engine running Wiggle Test mode has been achieved. Tap, move and wiggle the suspected sensor and/or harness area. If a fault is detected, a code may be stored in memory and indicated at the diagnostic tester or Scan tool. Record or retrieve code and perform CIRCUIT TEST indicated in Continuous Memory Codes chart. See TESTS W/CODES article.

ROUTINE 200 - NO CRANK & NO START

ROUTINE 200 - NO CRANK & NO START

ROUTINE 201 - CRANKS NORMALLY BUT WON'T START

Note. Extended cranking due to a "NO START" condition, can load exhaust system with raw fuel. This can ruin the catalytic converter after engine is started. After a "NO START" condition has been repaired, disconnect the thermactor air supply, run the engine until surplus fuel is used up and reconnect the thermactor air supply.

CRANKS NORMALLY BUT WON'T START

ROUTINE 202 - CRANKS NORMALLY BUT WON'T RUN (STALLS)

CRANKS NORMALLY BUT WON'T RUN (STALLS)

ROUTINE 203 - Cranks NORMALLY BUT SLOW TO START

Note. It is a good practice to confirm that the correct starting procedure was being used by the customer proceeding with diagnosis.

CRANKS NORMALLY BUT SLOW TO START

ROUTINE 204 - ROUGH IDLE

ROUGH IDLE

ROUTINE 205 - MISSES UNDER LOAD

MISSES UNDER LOAD

ROUTINE 206 - LOW IDLE (STALLS ON DECEL OR QUICK STOP)

LOW IDLE (STALLS ON DECEL OR QUICK STOP)

ROUTINE 207 - HESITATES OR STALLS ON ACCELERATION

HESITATES OR STALLS ON ACCELERATION

ROUTINE 208 - BACKFIRE (INTAKE OR EXHAUST)

BACKFIRE (INTAKE OR EXHAUST)

ROUTINE 209 - LACK OF POWER

LACK OF POWER

ROUTINE 210 - SURGES AT STEADY SPEED

SURGES AT STEADY SPEED

ROUTINE 212 - ENGINE NOISE

ENGINE NOISE

ROUTINE 213 - POOR FUEL ECONOMY

Note. Since Fuel consumption is drastically increased for city driving, short-run operation, stop and go driving, trailer towing, extended winter warm-up periods, etc., as opposed to "trip", mileage, an attempt should be made to determine these factors when confronted with "poor mileage" conditions. However, since the operator is not always at fault, the following is appended.

POOR FUEL ECONOMY

ROUTINE 214 - HIGH OIL CONSUMPTION

Note. If the condition can not be verified, clean engine, if necessary, change oil and Filter (at customer expense), seal and have customer drive 500 miles (804.5 Km) or enough Distance to consume two quarts before returning for re- examination.

HIGH OIL CONSUMPTION

ROUTINE 215 - SPARK KNOCK (PINGS)

Note. If the above fails to correct the condition, it is recommended that the owner change his source of Fuel and use higher octane Fuel.

SPARK KNOCK (PINGS)

ROUTINE 216 - ENGINE VIBRATES AT NORMAL OR HIGH Speed

ENGINE VIBRATES AT NORMAL OR HIGH Speed

ROUTINE 217 - ENGINE RUNS COLD

ENGINE RUNS COLD

ROUTINE 218 - ENGINE RUNS HOT

ENGINE RUNS HOT

ROUTINE 219 - Exhaust SMOKE

Note. White smoke is normal during warm-up.

EXHAUST SMOKE

ROUTINE 220 - GAS SMELL

GAS SMELL

ROUTINE 221 - "CHECK ENGINE" OR "SERVICE ENGINE SOON" LIGHT ALWAYS OR NEVER ON "CHECK ENGINE"/"CHECK DCL" MESSAGE ON

"CHECK ENG/SERV SOON" LIGHT ALWAYS/NEVER ON

ROUTINE 222 - STATE EMISSION TEST FAILURE

Note. Canada and some states or metropolitan areas in the United states require periodic Idle Emission Tests. All Ford products have been designed to pass these tests. If a Ford product fails an Idle Emission Test, it is probable that 1) The engine temperature was not warm and stabilized prior to the test. 2) The vehicle had Idle excessively long prior to the test.

Prior to starting any repairs, complaints of Idle Emission Test failure should be verified. The following example encompasses most of the emissions measurements modes of the current state Idle test procedures

1. Ensure that the engine is at normal operating temperature and that all accessories are turned off.
2. Read emissions at Idle.
3. Run engine at 2500+* 300 RPM.
4. Read emissions within 30 seconds.
5. Return engine Speed to Idle.
6. Read emissions within 30 seconds.

If any emission Components are replaced, Keep Alive Memory (KAM) should be cleared before repeating State Emission Test procedure. Refer to Quick Test Appendix.

STATE EMISSION TEST FAILURE

ROUTINE 223 - IMPROPER Shift

IMPROPER SHIFT

ROUTINE 224 - SHIFT INDICATOR LIGHT (SIL) & AUDIBLE CHIMES

"ON"

Note. Verify that the customer has read the owners manual on the new 3.8L SC overheat protection feature.

The 3.8L SC is equipped with a Shift indicator light and audible chime that warns the customer when the engine oil or coolant overheats while the vehicle is operated at high Speeds (above 100 MPH) for extended periods of time. The Shift indicator light and chime will also warn the customer when the engine has reached too high an RPM for that gear.

The EEC-IV processor will reduce vehicle Speed by limiting Fuel to the engine when one of these overheat conditions has been reached. The customer may then notice a loss of power and/or a slight vibration. The Shift indicator light will illuminate and the audible chime will produce a steady tone, alerting the customer to upshift at this time. Full power will be restored and the Shift indicator light and chimes will turn off when the vehicle returns to normal operating temperatures.

SHIFT INDICATOR LIGHT (SIL) & AUDIBLE CHIMES

GLOW PLUG TESTING

Scheme 97

CHECK GLOW PLUGS

With ignition off, disconnect glow plug connectors at glow plugs. Connect a 12-volt test light between a convenient power source and each glow plug terminal. If test light illuminates, go to next test. If test light does not illuminate, replace glow plug and go to next test.

CHECK HARNESS

With ignition off, disconnect glow plug connectors at glow plugs. Squeeze sides of glow plug module protective cover and remove cover. Using an ohmmeter or test light, check continuity between each glow plug lead and test terminal of glow plug module. (Scheme 97) If all leads check okay, go to next test. If any lead has an open circuit or is shorted to ground, repair or replace lead as necessary then go to next test.

CHECK CONTROL UNIT

Ensure ignition switch is off. Connect an ohmmeter between glow plug module ground wire terminal eyelet and negative battery terminal of each battery. (Scheme 97) If less than one ohm is indicated, go to next test. If greater than one ohm is indicated, clean or repair ground connection then go to next test.

CHECK SUPPLY VOLTAGE

Ensure ignition switch is off. Connect voltmeter positive lead to glow plug module positive terminal. (Scheme 97) Connect voltmeter negative lead to ground. If voltage is 10 volts or more, go to next test. If voltage is less than 10 volts, repair power supply wiring or recharge battery then go to next test.

CHECK VOLTAGE FROM IGNITION SWITCH

Connect voltmeter positive lead to glow plug module ignition terminal. (Scheme 97) Connect voltmeter negative lead to ground. Turn ignition switch to ON position. If voltage is 8 volts or more, go to next test. If voltage is less than 8 volts, check fusible link, repair wiring or recharge battery as necessary. Go to next test.

Scheme 98

1. With ignition switch off, connect a 12-volt test light between glow plug module test terminal and ground. (Scheme 97) Position test light so that it can be seen from driver's seat. Turn ignition switch to ON position and monitor test light. Compare test light times to chart. (Scheme 98) Total test light ON time includes time from the beginning of the initial ON cycle to the end of the last ON-OFF cycle measured in seconds. NOTE: The "WAIT-TO-START" indicator and/or test light may not illuminate if engine temperature is at or near operating temperature.
2. If test light times are within specifications, system is functioning correctly. End of test. If test light times are not within specifications, disconnect both batteries and replace glow plug module. Repeat FUNCTIONAL TEST.

1.9L SYMPTOM-TO-DIAGNOSTIC FLOW CHART MENU

1.9L EEC-IV SYMPTOM DIAGNOSTIC

2.3L SYMPTOM-TO-DIAGNOSTIC FLOW CHART MENU

2.3L EEC-IV SYMPTOM DIAGNOSTIC

2.5L SYMPTOM-TO-DIAGNOSTIC FLOW CHART MENU

2.5L EEC-IV SYMPTOM DIAGNOSTIC

3.0L SYMPTOM-TO-DIAGNOSTIC FLOW CHART MENU

3.0L EEC-IV SYMPTOM DIAGNOSTIC

3.8L SYMPTOM-TO-DIAGNOSTIC FLOW CHART MENU

3.8L EEC-IV SYMPTOM DIAGNOSTIC

5.0L SYMPTOM-TO-DIAGNOSTIC FLOW CHART MENU

5.0L EEC-IV SYMPTOM DIAGNOSTIC