GM Service Manual Online
For 1990-2009 cars only

The Engine Scan Tool Data List contains all engine related parameters that are available on the scan tool. The list is arranged in alphabetical order. A parameter may appear in any one of the data lists, and in some cases may appear more than once, or in more than one data list in order to group certain related parameters together.

Use the Engine Scan Tool Data List only after the following conditions are determined:

    •  The Diagnostic System Check-Engine Controls is completed.
    •  There are no diagnostic trouble codes (DTCs).
    • The On-Board diagnostics are functioning properly.

Scan tool values from a properly running engine may be used for comparison with the engine you are diagnosing. The Engine Scan Tool Data List represents the values that would be seen on a normal running engine.

Important: Do not use a scan tool that displays faulty data. The scan tool concern should be reported to the manufacturer. Use of a faulty scan tool can result in misdiagnosis and in unnecessary parts replacement.

Only the parameters listed below are referenced in this service manual for use in diagnosis. If all values are within the typical range described below, refer to Symptoms - Engine Controls for diagnosis.

The column labeled Data List indicates where a parameter is located on the scan tool. Review the scan tool operating manual for the exact locations of the data lists. The following is a description of each term listed:

All: The Parameter is in all data lists indicated below.

Input: General Info-Inputs

Output: General Info-Outputs

FE: Fuel and Emissions

Ign: Ignition

MF: Misfire

Aux: Auxiliary Emissions

Idle: Idle/Speed Control

Eng: Engineering

FF: Freeze Frame Data List

FR: Failure Record Data List

Scan Tool Parameter

Data List

Parameter Range/Units

Typical Data Values

Engine Idling/Radiator Hose Hot/Park or Neutral/Closed Loop/Accessories Off

A/C High Side Pressure

Input

0-3,450 kPa / 0-500 psi

Varies

A/C High Side Pressure Sensor

Input, Output

0-5 Volts

Varies

A/C Relay Command

Input, Output, Idle

On/Off

Off

A/C Request

Input, Idle

Yes/No

No

APP at Idle

Idle

Yes/No

Yes

APP Sensor 1

Input, FE, Idle

0.9-4.5 Volts

1 Volt

APP Sensor 2

Input, FE, Idle

0.45-2.25 Volts

0.5 Volt

Battery Voltage

All

0-25.5 Volts

12.8-14.2 Volts

Brake Switch

Input, Idle

Applied/Released

Released

CMP Active Counter

Input, Ign

0-256 Counts

Varies

Cruise Clutch Switch (If Equipped)

Input, Idle

Applied/Released

Released

Cruise Switch

Input, Idle

On/Off

Off

Cruise Brake Switch

Input, Idle

Applied/Released

Released

Cruise Resume/Accel.

Input, idle

On/Off

Off

Cruise Set/Coast

Input, idle

On/Off

Off

Desired Idle Speed

Idle

0-7,000 RPM

650 RPM

ECT

ALL

-39 to +140°C/-38 to +284°F

85-105  °C/185-220°F

Engine Load

ALL

0-99%

2%

Engine Oil Life Left

Input

0-100%

Varies

EGR Duty Cycle

Input, Output, FE, Ign, MF, Aux, Idle

0-100%

0%

EGR Sensor

Input, Aux

0-5 Volts

.82 Volts

Engine Run Time

ALL

0:00:00

Varies

Engine Speed

ALL

RPM

650 RPM

EVAP Purge Solenoid DC

Output, FE, Aux

0-100%

Varies

EVAP Vent Solenoid

Output

On/Off

Off

Fan Speed

Output

Off/Low/High

Varies

Fan Control 1

Output

On/Off

Varies

Fan Control 2

Output

On/Off

Varies

Fuel Level

Input, Ign

Gal/L

Varies

Fuel Level

Input, FE, Ign

0-5 Volts

Varies

Fuel Pump Relay Command

Output

On/Off

On

Fuel Shut-off Main

Eng

Yes/No

No

Fuel Shut-off Sec

Eng

Yes/No

No

Fuel Tank Pressure

Input, Aux

in H2O/mm Hg

Varies

Fuel Tank Press

Input, Aux

0-5 Volts

Varies

GEN L-Terminal

Input

High/Low

High

HO2S Bank 1 or Bank 2 Sensor 1

Input, FE, Aux

0-1 Volt

Varies between 0-1 Volt

HO2S Bank 1 or Bank 2 Sensor 2

Input, FE, Aux

0-1000 mV

Varies 400-800 mV

HO2S Bank 1 or Bank 2 Sen. 1 ohms

FE

0-∞

0

HO2S Bank 1 or Bank 2 Sen. 2 ohms

FE

0-∞

0

HO2S Bn 1 or Bn 2 Sen. 1 Heater

FE

On/Off

Varies

HO2S Bn 1 or Bn 2 Sen. 1 Heater

FE

On/Off

Varies

IAT

ALL

-39 to +140°C/-38 to +284°F

Varies

Ignition On

Input

Yes/No

Yes

Injector Pulse Width

FE

0-100 ms

3.0-5.4 ms

Intake Plenum Switchover Valve

Output

On/Off

Off

Knock Sensor 1

Ign

Active/Inactive

Inactive

Knock Sensor 2

Ign

Active/Inactive

Inactive

Knock Sensor 1

Input, Ign

0.25-2.67 Volts

1.10 Volts

Knock Sensor 2

Input, Ign

0.25-2.67 Volts

1.10 Volts

Knock Retard Cyl. 1-6

Ign

0-191 Degrees

0 Degrees

Low Oil Pressure

Input

Yes/No

No

LT FT Bn. 1 or Bn. 2 Cruise/Accel.

FE, Aux

-100 to 100%

0%

LT FT Bn. 1 or Bn. 2 Idle/Decel.

FE, Aux

-100 to +100%

0%

Loop Status Bank 1 or Bank 2

FE

Open/Closed

Closed

MAF

ALL

0-655 g/s

3.4-6.3 g/s

MAF Sensor

Input

0-5 Volts

1.2-1.5 Volts

Main Relay Command

Output

On/Off

On

MAP

ALL

kPa/Volts

45

Misfire Current Cyl. 1-6

MF

0-255 Counts

0

Misfire History Cyl. 1-6

MF

0-255 Counts

0

Park/Neutral Switch (If Equipped)

Idle

P-N/R-D-L

P-N

Short Term FT Bank 1 or Bank 2

FE, Aux

-100 to +100%

-3% to +3%

Spark

Ign

-133 to +78 Degrees

2-5 Degrees

TAC Learn Counter

Eng

0-255 Counts

Varies

TAC Limit Authority

Eng

Yes/No

No

TAC Limit Power

Eng

Yes/No

No

Torque Delivered

Input

0-100%

0%

Torque Requested

Input

0-100%

100%

TP Angle

ALL

0-99%

0 percent

TP Sensor 1

Input, FE, Idle

0-5 Volts

0.5-0.8 Volts

TP Sensor 2

Input, FE, Idle

0-5 Volts

4.1-4.5 Volts

Vehicle Speed

ALL

km/mi

Varies