Introduction

NOTE: The descriptions and specifications contained in this information were in effect at the time it was approved for publication. Ford Motor Company reserves the right to discontinue models at any time, or change specifications or design without notice and without incurring any obligation.

Important Safety Notice
Appropriate service methods and procedures are essential for the safe, reliable operation of all motor vehicles as well as the personal safety of the individual doing the work. This information provides general directions for performing service with tested, effective techniques. Following them will help assure reliability.

There are numerous variations in procedure, techniques, tools and parts for servicing vehicles, as well as in the skill of the individual doing the work. This information cannot possibly anticipate all such variations and provide advice or cautions as to each. Accordingly, anyone who departs from the instructions provided must first establish that he compromises neither his personal safety nor the vehicle integrity by his choice of methods, tools or parts.

Notes, Cautions, and Warnings
As you read through the procedures, you will come across NOTES, CAUTIONS, and WARNINGS. Each one is there for a specific purpose. NOTES give you added information that will help you to perform a particular procedure. CAUTIONS are given to prevent you from making an error that could damage the vehicle. WARNINGS remind you to be especially careful in those areas where carelessness can cause you personal injury. The following list contains some general WARNINGS that you should follow when you work on a vehicle.
^ ALWAYS WEAR SAFETY GLASSES FOR EYE PROTECTION.
^ USE SAFETY STANDS WHENEVER A PROCEDURE REQUIRES YOU TO BE UNDER THE VEHICLE.
^ MAKE SURE THAT THE IGNITION SWITCH IS ALWAYS IN THE OFF POSITION, UNLESS OTHERWISE REQUIRED BY THE PROCEDURE.
^ SET THE PARKING BRAKE WHEN WORKING ON THE VEHICLE. IF YOU HAVE AN AUTOMATIC TRANSMISSION, SET IN PARK UNLESS INSTRUCTED OTHERWISE FOR A SPECIFIC OPERATION. IF YOU HAVE A MANUAL TRANSMISSION, IT SHOULD BE IN REVERSE (ENGINE OFF) OR NEUTRAL (ENGINE ON) UNLESS INSTRUCTED OTHERWISE FOR A SPECIFIC OPERATION. PLACE WOOD BLOCKS (4" X 4" OR LARGER) AGAINST THE FRONT AND REAR SURFACES OF THE TIRES TO HELP PREVENT THE VEHICLE FROM MOVING.
^ OPERATE THE ENGINE ONLY IN A WELL-VENTILATED AREA TO AVOID THE DANGER OF CARBON MONOXIDE POISONING.
^ KEEP YOURSELF AND YOUR CLOTHING AWAY FROM MOVING PARTS WHEN THE ENGINE IS RUNNING, ESPECIALLY THE DRIVE BELTS.
^ TO PREVENT SERIOUS BURNS, AVOID CONTACT WITH HOT METAL PARTS SUCH AS THE RADIATOR, EXHAUST MANIFOLD, TAIL PIPE, THREE-WAY CATALYTIC CONVERTER AND MUFFLER.
^ DO NOT SMOKE WHILE WORKING ON A VEHICLE.
^ TO AVOID INJURY, ALWAYS REMOVE RINGS, WATCHES, LOOSE HANGING JEWELRY AND LOOSE CLOTHING BEFORE BEGINNING TO WORK ON A VEHICLE.
^ WHEN IT IS NECESSARY TO WORK UNDER THE HOOD, KEEP HANDS AND OTHER OBJECTS CLEAR OF THE RADIATOR FAN BLADES!

Preface
This information provides a step-by-step approach for diagnosing driveability, emission and powertrain control system symptoms. Before beginning diagnosis, it may be helpful to reference any Technical Service Bulletins (TSBs) or On-line Automotive Service Information System (OASIS) information when this is available.

This information is used in conjunction with the Body, Chassis, Powertrain, Drivetrain vehicle systems and the Vehicle/Diagrams. The vehicle systems information is used to provide additional diagnostics when directed by these procedures. The vehicle system information is also used for component removal and replacement information. Refer to Vehicle/Diagrams for vehicle-specific wiring information and component, connector and splice location.

The following is a description of the information contained for diagnosis.

Description And Operation
Description and Operation contains description and operation information on powertrain control systems and components. It is designed to give the technician a general knowledge of the powertrain control system. It should be used when general information about the powertrain control system is desired, and is rarely referenced from other vehicle system.

Diagnostic Methods
Diagnostic Methods contains information on specific diagnostic tasks that are used during diagnosis. Descriptions of specific diagnostic methods are included, as well as detailed instructions on how to access or perform the tasks. It provides the technician with step-by-step instructions for performing routine diagnostic tasks.

Symptom Charts
All diagnosis begins in Symptom Charts with the Symptom Index. The Symptom Index contains the list of symptoms. The Symptom Index will refer the technician to the appropriate Symptom Chart, which guides the technician through diagnosis.

Diagnostic Subroutines
Diagnostic Subroutines contains the Hard Start/No Start and Performance Diagnostic Procedures that are used to obtain quick diagnostic information. This information also contains the Powertrain Diagnostic Trouble Code (DTC) "Go To" Charts. Symptom Charts will direct the technician to these tests when required.

Pinpoint Tests
All the pinpoint tests are included in Pinpoint Tests. Never enter a Pinpoint Test unless directed there. When directed to a Pinpoint Test, always read the information and look at the schematic included at the beginning of the Pinpoint Test.

Reference Values
Reference Values contains the Control System Diagnostic Sheet Reference Chart.

How To Use The Diagnostic Procedures

Customer Information Worksheet:

^ Use the information about the vehicle driveability or emission concern (from the service write-up or the Customer Information Worksheet) to attempt to verify/re-create the symptom. Look for any vehicle modifications or aftermarket items that may contribute to the symptom. A check of any applicable TSBs or OASIS messages may be useful, if this information is available.
^ Refer to the Symptom Index (Symptom Charts), and select the symptom that best describes the vehicle symptom. (For multiple symptoms, select the one that is most noticeable.)
^ Go to the Symptom Chart indicated in the Symptom Index.
^ Begin the Chart at step number 1.
^ Follow the instructions in the step.
- If the step contains a test procedure or question (without a reference outside the step), perform the test step/answer the question and continue as directed.
- If the step sends you to a specific area for testing (for example Hard Start/No Start Procedures, a Pinpoint Test Step), go to the procedures. Follow the directions given in those procedures, including directions to other tests at other vehicle systems. If a damaged part is found, repair/replace as directed. If no fault is found, and diagnosis in that area is complete, return to the Symptom Chart and continue as directed.
^ During diagnosis, if directed to test a system/component that is not contained on that vehicle, proceed to the next step.
^ If the Symptom Chart for the vehicle symptom is completed and no fault is found, return to the Symptom Index to address the next most prominent symptom.
^ After service, verify that the vehicle is operating properly and the original symptom is eliminated.

NOTE: If a symptom is determined to be intermittent, careful visual and physical underhood inspection of connectors, wiring harnesses, vacuum lines and components is required. The Customer Information Worksheet may contain more detailed symptom information. Before an in-depth diagnosis begins, start the engine and wiggle wires, tap on components, etc., while listening for an indication of a concern (such as rpm change or relay clicking).

Information about engine conditions is stored when a Diagnostic Trouble Code (DTC) that lights the Malfunction Indicator Lamp (MIL) is set.