Innova OBD2 User manual

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Table of Contents
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Title Page No.
INTRODUCTION
What is OBD? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
YOU CAN DO IT! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
SAFETY PRECAUTIONS
Safety First! . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
ABOUT THE SCAN TOOL
Vehicles Covered . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Battery Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Adjustments and Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
SCAN TOOL CONTROLS
Controls and Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Display Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
ONBOARD DIAGNOSTICS
Diagnostic Trouble Codes (DTCs) . . . . . . . . . . . . . . . . . . . . . . 15
PREPARATION FOR TESTING
Preliminary Vehicle Diagnosis Worksheet . . . . . . . . . . . . . . . . 17
Before You Begin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Vehicle Service Manuals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
USING THE SCAN TOOL
Code Retrieval Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Erasing Diagnostic Trouble Codes (DTCs) . . . . . . . . . . . . . . . . 27
I/M Readiness Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
LIVE DATA MODE
Viewing Live Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Customizing Live Data (PIDs) . . . . . . . . . . . . . . . . . . . . . . . . . 36
Recording (Capturing) Live Data . . . . . . . . . . . . . . . . . . . . . . . 37
Live Data Playback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
ADDITIONAL TESTS
O2 Sensor Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Non-Continuous Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
System Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Vehicle Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
GENERIC (GLOBAL) OBD2 PID LIST . . . . . . . . . . . . . . . . . . . . . . . 50
GLOSSARY
Glossary of Terms and Abbreviations . . . . . . . . . . . . . . . . . . . 55
WARRANTY AND SERVICING
Limited One Year Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Service Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Introduction
WHAT IS OBD?
OBD2 1
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WHAT IS OBD?
The OBD2 Scan Tool is designed to work on all OBD 2 compliant
vehicles. All 1996 and newer vehicles (cars, light trucks and
SUVs) sold in the United States are OBD 2 compliant.
One of the most exciting improvements
in the automobile industry was the addition
of on-board diagnostics (OBD) on vehicles,
or in more basic terms, the computer that
activates the vehicle’s “CHECK ENGINE”
light. OBD 1 was designed to monitor manu-
facturer-specific systems on vehicles built
from 1981 to 1995. Then came the develop-
ment of OBD 2, which is on all 1996 cars and light trucks sold in the
U.S. Like its predecessor, OBD 2 was adopted as part of a government
mandate to lower vehicle emissions. But what makes OBD 2 unique is
its universal application for all late model cars and trucks - domestic
and import. This sophisticated program in the vehicle’s main computer
system is designed to detect failures in a range of systems, and can
be accessed through a universal OBD 2 port, which is usually found
under the dashboard. For all OBD systems, if a problem is found, the
computer turns on the “CHECK ENGINE” light to warn the driver, and
sets a Diagnostic Trouble Code (DTC) to identify where the problem
occurred. A special diagnostic tool, such as the OBD2 Scan Tool, is
required to retrieve these codes, which consumers and professionals
use as a starting point for repairs.

You Can Do It!
EASY TO USE - EASY TO VIEW - EASY TO DEFINE
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Easy To Use ....
■Connect the Scan Tool to the vehi-
cle’s test connector.
■Turn the ignition key "On.”
■Press the LINK button.
Easy To View ....
■The Scan Tool retrieves stored codes,
Freeze Frame data and I/M Readiness
status.
■Codes, I/M Readiness status and
Freeze Frame data are displayed on the
Scan Tool’s display screen. System sta-
tus is indicated by LED indicators.
Easy To Define ....
■Read code definitions from the Scan
Tool’s display.
■View Freeze Frame data.
■View Live Data.

Safety Precautions
SAFETY FIRST!
OBD2 3
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SAFETY FIRST!
This manual describes common test procedures used by
experienced service technicians. Many test procedures
require precautions to avoid accidents that can result in
personal injury, and/or damage to your vehicle or test
equipment. Always read your vehicle's service manual and
follow its safety precautions before and during any test or
service procedure. ALWAYS observe the following general
safety precautions:
When an engine is running, it produces carbon monox-
ide, a toxic and poisonous gas.To prevent serious injury
or death from carbon monoxide poisoning, operate the
vehicle ONLY in a well-ventilated area.
To protect your eyes from propelled objects as well as
hot or caustic liquids, always wear approved safety
eye protection.
When an engine is running, many parts (such as the
coolant fan, pulleys, fan belt etc.) turn at high speed. To
avoid serious injury, always be aware of moving parts.
Keep a safe distance from these parts as well as other
potentially moving objects.
Engine parts become very hot when the engine is run-
ning. To prevent severe burns, avoid contact with hot
engine parts.
Before starting an engine for testing or trouble-shoot-
ing, make sure the parking brake is engaged. Put the
transmission in park (for automatic transmission) or
neutral (for manual transmission). Block the drive
wheels with suitable blocks.
Connecting or disconnecting test equipment when the
ignition is ON can damage test equipment and the vehi-
cle's electronic components. Turn the ignition OFF
before connecting the Scan Tool to or disconnecting the
Scan Tool from the vehicle’s Data Link Connector
(DLC).
To avoid personal injury, instrument damage and/or
damage to your vehicle; do not use the OBD2 Scan Tool
before reading this manual.
N
L
D
R
P

Safety Precautions
SAFETY FIRST!
4 OBD2
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To prevent damage to the on-board computer when tak-
ing vehicle electrical measurements, always use a digi-
tal multimeter with at least 10 megOhms of impedance.
Fuel and battery vapors are highly flammable. To pre-
vent an explosion, keep all sparks, heated items and
open flames away from the battery and fuel / fuel
vapors. DO NOT SMOKE NEAR THE VEHICLE DUR-
ING TESTING.
Don't wear loose clothing or jewelry when working on an
engine. Loose clothing can become caught in the fan,
pulleys, belts, etc. Jewelry is highly conductive, and can
cause a severe burn if it makes contact between a
power source and ground.

About the Scan Tool
VEHICLES COVERED
OBD2 5
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VEHICLES COVERED
The OBD2 Scan Tool is designed to work on all OBD 2 compliant vehi-
cles. All 1996 and newer vehicles (cars and light trucks) sold in the
United States are OBD 2 compliant.
Federal law requires that all 1996 and newer cars and light
trucks sold in the United States must be OBD 2 compliant;
this includes all Domestic, Asian and European vehicles.
Some 1994 and 1995 vehicles are OBD 2 compliant. To find out if a
1994 or 1995 vehicle is OBD 2 compliant, check the following:
1. The Vehicle Emissions Control Information (VECI) Label. This
label is located under the hood or by the radiator of most vehicles. If
the vehicle is OBD 2 compliant, the label will state “OBD II Certified.”
2. Government Regulations require that
all OBD 2 compliant vehicles must
have a “common” sixteen-pin Data
Link Connector (DLC).
Some 1994 and 1995 vehicles have 16-pin connectors but
are not OBD 2 compliant. Only those vehicles with a Vehicle
Emissions Control Label stating “OBD II Certified” are OBD 2
compliant.
Data Link Connector (DLC) Location
The 16-pin DLC is usually
located under the instrument
panel (dash), within 12 inches
(300 mm) of center of the
panel, on the driver’s side of
most vehicles. It should be eas-
ily accessible and visible from
a kneeling position outside the
vehicle with the door open.
VEHICLE EMISSION CONTROL INFORMATION
VEHICLE
MANUFACTURER
OBD II
CERTIFIED
ENGINE FAMILY EFN2.6YBT2BA
DISPLACEMENT 2.6L
THIS VEHICLE CONFORMS TO U.S. EPA AND STATE
OF CALIFORNIA REGULATIONS APPLICABLE TO
1999 MODEL YEAR NEW TLEV PASSENGER CARS.
REFER TO SERVICE MANUAL FOR ADDITIONAL INFORMATION
TUNE-UP CONDITIONS: NORMAL OPERATING ENGINE TEMPERATURE,
ACCESSORIES OFF, COOLING FAN OFF, TRANSMISSION IN NEUTRAL
SPARK PLUG
TYPE NGK BPRE-11
GAP: 1.1MM
CATALYST
EXHAUST EMISSIONS STANDARDS STANDARD CATEGORY
CERTIFICATION
IN-USE
TLEV
TLEV INTERMEDIATE
OBD II
CERTIFIED
12345678
9 10111213141516
NEAR
CENTER
OF DASH
BEHIND
ASHTRAY
LEFT CORNER
OF DASH

About the Scan Tool
VEHICLES COVERED / BATTERY REPLACEMENT
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On some Asian and European vehicles the DLC is located
behind the “ashtray” (the ashtray must be removed to access
it) or on the far left corner of the dash. If the DLC cannot be
located, consult the vehicle’s service manual for the location.
BATTERY REPLACEMENT
Replace batteries when the battery symbol is visible on display
and/or the 3 LEDS are all lit and no other data is visible on screen.
1. Locate the battery cover on the back of the Scan Tool.
2. Slide the battery cover off (use your fingers).
3. Replace batteries with three AA-size batteries (for longer life, use
Alkaline-type batteries).
4. Reinstall the battery cover on the back of the Scan Tool.
Language Selection After Battery Installation
The first time the Scan Tool is turned on, you must select the desired
display language (English, French or Spanish). Select the display lan-
guage as follows:
1. Press and hold the POWER/LINK
button for approximately 3 seconds to
turn the Scan Tool “ON.”
■The Select Language screen displays.
2. Use the UP and DOWN but-
tons, as necessary, to highlight the
desired display language.
3. When the desired display language is
selected, press the ENTER/LD
button to confirm your selection.
■The display shows the "To Link" mes-
sage in the selected display lan-
guage. Press the POWER/LINK
button to turn the Scan Tool "off."
■After the initial language selection is performed, it as well as
other settings can be changed as desired. See ADJUSTMENTS
AND SETTINGS on page 7 for further instructions.

About the Scan Tool
ADJUSTMENTS AND SETTINGS
OBD2 7
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ADJUSTMENTS AND SETTINGS
The OBD2 Scan Tool lets you make several adjustments and settings
to configure the Scan Tool for your particular needs. The following
adjustments and settings are available:
■DTC Library - Library of OBD2 DTC definitions.
■Adjust Brightness: Adjusts the brightness of the display screen.
■Display Backlight: Turns the display backlight on and off.
■Select Language: Sets the display language for the Scan Tool to
English, French or Spanish.
■Unit of Measure: Sets the Unit of Measure for the Scan Tool’s dis-
play to USA or metric.
Adjustments and settings can be made only when the Scan
Tool is NOT connected to a vehicle.
To enter the MENU Mode:
1. With the Scan Tool “off”, press and hold
the UP button, then press and
release the POWER/LINK button.
■The adjustments and setting MENU
displays.
2. Release the UP button.
DO NOT release the UP button until the adjustments and
settings MENU is visible on the display.
3. Make adjustments and settings as described in the following para-
graphs.
Searching for a DTC Definition Using the DTC Library
1. Use the UP and DOWN but-
tons, as necessary, to highlight DTC
Library in the MENU, then press the
ENTER/LD button.
■The Enter DTC screen displays. The
screen shows the code “P0000”, with
the “P” flashing.
2. Use the UP and DOWN buttons,
as necessary, to scroll to the desired
DTC type (P=Powertrain, U=Network,
B=Body, C=Chassis), then press the
DTC SCROLL button.

About the Scan Tool
ADJUSTMENTS AND SETTINGS
8 OBD2
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■The selected character displays “solid”, and the next character
begins flashing.
3. Select the remaining characters in the DTC in the same way, press-
ing the DTC SCROLL button to confirm each character. When
you have selected all the DTC characters, press the ENTER/LD
button to view the DTC definiition.
■If you entered a “Generic” DTC
(DTCs that start with “P0”, “P2” and
some “P3”):
- The selected DTC and DTC defi-
nition (if available) show on the
Scan Tool’s display.
■If you entered a “Manufacturer-
Specific” DTC (DTCs that start with
“P1” and some “P3”):
- The “Select Manufacturer” screen
displays.
- Use the UP and DOWN
buttons, as necessary, to high-
light the appropriate manufactur-
er, then press the ENTER/LD
button to display the correct
DTC for your vehicle.
If a definition for the DTC you
entered is not available, an advi-
sory message shows on the Scan
Tool’s display.
4. If you wish to view definitions for additional DTCs, press the
ENTER/LD button to return to the Enter DTC screen, and
repeat steps 2 and 3.
5. When all desired DTCs have been viewed, press the ERASE
button to exit the DTC Library.
Adjusting Display Brightness
1. Use the UP and DOWN but-
tons, as necessary, to highlight Adjust
Brightness in the MENU, then press
the ENTER/LD button.
■The Adjust Brightness screen dis-
plays.

About the Scan Tool
ADJUSTMENTS AND SETTINGS
OBD2 9
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■The Brightness field shows the cur-
rent brightness setting, from 0 to 43.
2. Press the UP button to decrease
the brightness of the display (make the
display darker).
3. Press the DOWN button to increase
the brightness of the display (make the
display lighter).
4. When the desired brightness is obtained, press the ENTER/LD
button to save your changes and return to the MENU.
Using the Backlight
1. Use the UP and DOWN but-
tons, as necessary, to highlight Display
Backlight in the MENU, then press the
ENTER/LD button.
■The Display Backlight screen displays.
2. Press the UP or DOWN button,
as necessary, to select the desired
backlight mode, either ON or OFF.
3. When the desired backlight mode is
selected, press the ENTER/LD
button to save your changes.
■The display returns to the MENU, and
the backlight turns “on” or “off” as
selected.
Selecting the Display Language
1. Use the UP and DOWN but-
tons, as necessary, to highlight Select
Language in the MENU, then press the
ENTER/LD button.
■The Select Language screen dis-
plays.
■The currently selected display
Language is highlighted.
2. Press the UP or DOWN button,
as necessary, to highlight the desired
display language.
3. When the desired display language is
highlighted, press the ENTER/LD
button to save your changes and return
to the MENU.

About the Scan Tool
ADJUSTMENTS AND SETTINGS
10 OBD2
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Setting the Unit of Measurement
1. Use the UP and DOWN but-
tons, as necessary, to highlight Unit of
Measurement in the MENU, then press
the ENTER/LD button.
2. Press the UP or DOWN button,
as necessary, to highlight the desired
Unit of Measurement.
3. When the desired Unit of Measurement
value is selected, press the ENTER/LD
button to save your changes.
Exiting the MENU Mode
1. Use the UP and DOWN buttons, as necessary, to highlight
Menu Exit in the MENU, then press the ENTER/LD button.
■The display returns to the DTC screen (if data is currently stored
in the Scan Tool) or to the "To Link" message (if no data is cur-
rently stored in the Scan Tool).

OBD2 11
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Scan Tool Controls
CONTROLS AND INDICATORS
CONTROLS AND INDICATORS
See Figure 1 for the locations of items 1 through 11, below.
1. ERASE button - Erases Diagnostic Trouble Codes (DTCs),
and “Freeze Frame” data from your vehicle’s computer, and resets
Monitor status.
2. DTC SCROLL button - Displays the DTC View screen and/or
scrolls the display to view DTCs when more than one DTC is present.
3. POWER/LINK button - When the Scan Tool IS NOT
connected to a vehicle, turns the Scan Tool “On” and “Off”. When the
Scan Tool is connected to a vehicle, links the Scan Tool to the vehicle’s
PCM to retrieve diagnostic data from the computer’s memory.
To turn the Scan Tool "On", you must press and hold the
POWER/LINK button for approximately 3 seconds.
4. ENTER/LIVE DATA button - When in MENU mode, confirms
the selected option or value. When linked to a vehicle, places the Scan
Tool in "Live Data" mode.
1
6
7
2
5
3
9
8
4
10
11
Figure 1. Controls and Indicators

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Scan Tool Controls
DISPLAY FUNCTIONS
5. DOWN button - When in MENU mode, scrolls DOWN through
the menu and submenu selection options. When LINKED to a vehicle,
scrolls DOWN through the current display screen to display any addi-
tional data.
6. UP button - When in MENU mode, scrolls UP through the
menu and submenu selection options. When LINKED to a vehicle,
scrolls UP through the current display screen to display any additional
data.
7. GREEN LED - Indicates that all engine systems are running nor-
mally (all Monitors on the vehicle are active and performing their diag-
nostic testing, and no DTCs are present).
8. YELLOW LED - Indicates there is a possible problem. A “Pending”
DTC is present and/or some of the vehicle’s emission monitors have
not run their diagnostic testing.
9. RED LED - Indicates there is a problem in one or more of the vehi-
cle’s systems. The red LED is also used to show that DTC(s) are pres-
ent. DTCs are shown on the Scan Tool’s display. In this case, the
Multifunction Indicator (“Check Engine”) lamp on the vehicle’s instru-
ment panel will light steady on.
10. Display - Displays settings Menu and submenus, test results,
Scan Tool functions and Monitor status information. See DISPLAY
FUNCTIONS, following, for more details.
11. CABLE - Connects the Scan Tool to the vehicle’s Data Link
Connector (DLC).
DISPLAY FUNCTIONS
See Figure 2 for the locations of items 1 through 16, following.
4
3
21
11 12 13
5
8
9
10
14
16
15
6
7
Figure 2. Display Functions

OBD2 13
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Scan Tool Controls
DISPLAY FUNCTIONS
1. I/M MONITOR STATUS field - Identifies the I/M Monitor status area.
2. Monitor icons - Indicate which Monitors are supported by the vehi-
cle under test, and whether or not the associated Monitor has run
its diagnostic testing (Monitor status). When a Monitor icon is solid,
it indicates that the associated Monitor has completed its diagnos-
tic testing. When a Monitor icon is flashing, it indicates that the vehi-
cle supports the associated Monitor, but the Monitor has not yet run
its diagnostic testing.
3. Vehicle icon - Indicates whether or not the Scan Tool is being
properly powered through the vehicle’s Data Link Connector (DLC).
A visible icon indicates that the Scan Tool is being powered through
the vehicle’s DLC connector.
4. Link icon - Indicates whether or not the Scan Tool is commu-
nicating (linked) with the vehicle’s on-board computer. When visible,
the Scan Tool is communicating with the computer. If the Link icon
is not visible, the Scan Tool is not communicating with the computer.
5. Computer icon - When this icon is visible it indicates that the
Scan Tool is linked to a personal computer. An optional “PC Link
Kit” is available that makes it possible to upload retrieved data to a
personal computer.
6. Scan Tool Internal Battery icon - When visible, indicates the
Scan Tool batteries are “low” and should be replaced. If the batter-
ies are not replaced when the battery symbol is "on", all 3 LEDs
will light up as a last resort indicator to warn you that the batteries
need replacement. No data will be displayed on screen when all 3
LEDs are lit.
7. DTC Display Area - Displays the Diagnostic Trouble Code (DTC) num-
ber. Each fault is assigned a code number that is specific to that fault.
8. Test Data Display Area - Displays DTC definitions, Freeze Frame
data, Live Data and other pertinent test information messages.
9. FREEZE FRAME icon - Indicates that there is Freeze Frame data
from “Priority Code” (Code #1) stored in the vehicle’s computer
memory.
10. HISTORY icon - Indicates the currently displayed DTC is a
“History” code.
11. PENDING icon - Indicates the currently displayed DTC is a
“Pending” code.
12. MIL icon - Indicates the status of the Malfunction Indicator Lamp
(MIL). The MIL icon is visible only when a DTC has commanded
the MIL on the vehicle’s dashboard to light.

14 OBD2
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Scan Tool Controls
DISPLAY FUNCTIONS
13. Code Number Sequence - The Scan Tool assigns a sequence
number to each DTC that is present in the computer’s memory,
starting with “01.” This number indicates which code is currently
displayed. Code number “01” is always the highest priority code,
and the one for which “Freeze Frame” data has been stored.
If “01” is a “Pending” code, there may or may not be
“Freeze Frame” data stored in memory.
14. Code Enumerator - Indicates the total number of codes retrieved
from the vehicle’s computer.
15. Generic DTC icon - When visible, indicates that the currently
displayed DTC is a “generic” or universal code.
16. Manufacturer Specific DTC icon - When visible, indicates that
the currently displayed DTC is a Manufacturer Specific Code.

OBD2 15
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Onboard Diagnostics
DIAGNOSTIC TROUBLE CODES (DTCs)
DIAGNOSTIC TROUBLE CODES (DTCs)
Diagnostic Trouble Codes (DTCs) are
meant to guide you to the proper serv-
ice procedure in the vehicle’s service
manual. DO NOT replace parts based
only on DTCs without first consulting
the vehicle’s service manual for prop-
er testing procedures for that particular
system, circuit or component.
DTCs are alphanumeric codes that are used to identify a
problem that is present in any of the systems that are mon-
itored by the on-board computer (PCM). Each trouble code
has an assigned message that identifies the circuit, compo-
nent or system area where the problem was found.
OBD 2 diagnostic trouble codes are made up of five charac-
ters:
■The 1st character is a letter. It identifies the “main system” where
the fault occurred (Body, Chassis, Powertrain, or Network).
■The 2nd character is a numeric digit. It identifies the “type” of code
(Generic or Manufacturer-Specific).
Generic DTCs are codes that are used by all vehicle manu-
facturers. The standards for generic DTCs, as well as their
definitions, are set by the Society of Automotive Engineers
(SAE).
Manufacturer-Specific DTCs are codes that are controlled
by the vehicle manufacturers. The Federal Government does
not require vehicle manufacturers to go beyond the stan-
dardized generic DTCs in order to comply with the new
OBD2 emissions standards. However, manufacturers are free
to expand beyond the standardized codes to make their sys-
tems easier to diagnose.
■The 3rd character is a numeric digit. It identifies the specific sys-
tem or sub-system where the problem is located.
■The 4th and 5th characters are numeric digits. They identify the
section of the system that is malfunctioning.
Diagnostic Trouble
Codes (DTCs) are
codes that identify a
specific problem area.

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Onboard Diagnostics
DIAGNOSTIC TROUBLE CODES (DTCs)
DTCs and MIL Status
When the vehicle’s on-board computer detects
a failure in an emissions-related component
or system, the computer’s internal diagnostic
program assigns a diagnostic trouble code
(DTC) that points to the system (and sub-
system) where the fault was found. The diag-
nostic program saves the code in the com-
puter’s memory. It records a “Freeze Frame” of
conditions present when the fault was found, and lights the Malfunction
Indicator Lamp (MIL). Some faults require detection for two trips in a
row before the MIL is turned on.
The “Malfunction Indicator Lamp” (MIL) is the accepted term
used to describe the lamp on the dashboard that lights to
warn the driver that an emissions-related fault has been
found. Some manufacturers may still call this lamp a “Check
Engine” or “Service Engine Soon” light.
P 0 2 0 1
B
C
P
U
-
-
-
-
Body
Chassis
Powertrain
Network
-
-
-
-
Generic
Manufacturer Specific
Generic
Includes both Generic and Manufacturer
Specific Codes
0
1
2
3
Identifies what section of the system
is malfunctioning
Identifies the system where the
problem is located:
1
2
3
4
5
6
7
8
-
-
-
-
-
-
-
-
Fuel and Air Metering
Fuel and Air Metering (injector circuit
malfunction only)
Ignition System or Misfire
Auxiliary Emission Control System
Vehicle Speed Control and Idle Control
System
Computer Output Circuits
Transmission
Transmission
OBD 2 DTC EXAMPLE
P0201 - Injector Circuit Malfunction, Cylinder 1

OBD2 17
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Preparation for Testing
PRELIMINARY VEHICLE DIAGNOSIS WORKSHEET
PRELIMINARY VEHICLE DIAGNOSIS WORKSHEET
The purpose of this form is to help you gather preliminary information on
your vehicle before you retrieve codes. By having a complete account of
your vehicle's current problem(s), you will be able to systematically pin-
point the problem(s) by comparing your answers to the fault codes you
retrieve.You can also provide this information to your mechanic to assist
in diagnosis and help avoid costly and unnecessary repairs. It is impor-
tant for you to complete this form to help you and/or your mechanic have
a clear understanding of your vehicle's problems.
NAME:
DATE:
VIN*:
YEAR:
MAKE:
MODEL:
ENGINE SIZE:
VEHICLE MILEAGE:
*VIN: Vehicle Identification Number, found at the base of the windshield
on a metallic plate, or at the driver door latch area (consult your vehicle
owner's manual for location).
TRANSMISSION:
❑Automatic
❑Manual
Please check all applicable items in each category.
DESCRIBE THE PROBLEM:

18 OBD2
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Preparation for Testing
PRELIMINARY VEHICLE DIAGNOSIS WORKSHEET
WHEN DID YOU FIRST NOTICE THE PROBLEM:
❑Just Started
❑Started Last Week
❑Started Last Month
❑Other:
LIST ANY REPAIRS DONE IN THE PAST SIX MONTHS:
PROBLEMS STARTING
ENGINE QUITS OR STALLS
IDLING CONDITIONS
RUNNING CONDITIONS
❑No symptoms
❑Will not crank
❑Cranks, but will not start
❑Starts, but takes a long time
❑No symptoms
❑Right after starting
❑When shifting into gear
❑During steady-speed driving
❑Right after vehicle comes to a stop
❑While idling
❑During acceleration
❑When parking
❑No symptoms
❑Is too slow at all times
❑Is too fast
❑Is sometimes too fast or too slow
❑Is rough or uneven
❑Fluctuates up and down
❑No symptoms
❑Runs rough
❑Lacks power
❑Bucks and jerks
❑Poor fuel economy
❑Hesitates or stumbles on
accelerations
❑Backfires
❑Misfires or cuts out
❑Engine knocks, pings or rattles
❑Surges
❑Dieseling or run-on