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 DTCs.
    • The on-board diagnostics are functioning correctly.

Scan tool values from an engine that is operating correctly 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 operating 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 may result in misdiagnosis and unnecessary parts replacement.

Only the parameters listed below are referenced in this service information for use in 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.

Eng 1: Engine Data 1

Eng 2: Engine Data 2

CC: Cruise Control Data

ET: Electrical/Theft Data

EVAP: EVAP Data

HO2S: HO2S Data

Ign: Ignition Data

Ind: Induction Data

MF: Misfire Data

TAC: Throttle Actuated Control Data

FF: Freeze Frame Data

FR: Failure Records Data

Scan Tool Parameter

Data List

Parameter Range/Units

Typical Data Values

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

A/C High Side Pressure

Eng 2

Volts

Varies

Actual EGR Position

Eng 1, Ind

%

Varies

Ambient Air Temperature

Eng 1, HO2S, Ind

Temperature

Varies

APP Sensor 1 and Sensor 2

TAC

Volts

Varies

APP Sensors

TAC

%

Varies

BARO

Eng 1, Eng 2, HO2S, Ind, MF

65-104 kPa

Varies with altitude

Change Engine Oil Indicator Command

Eng 2

On, Off

Off

Crank Request Signal

ET

Yes/No

No

Cruise Active

CC

On/Off

Off

Cruise Cancel Switch

CC

Active/Inactive

Inactive

Cruise Control Switch

CC

Normal/Failed

Normal

Cruise On/Off Switch

CC

On/Off

Off

Cruise Release Brake Pedal Switch

CC

Normal/Failed

Normal

Cruise Resume/Accel Switch

CC

On/Off

Off

Cruise Set/Accel Switch

CC

On/Off

Off

Cruise Resume/Accel. Switch

CC

Active/Inactive

Inactive

Cruise Set/Coast Switch

CC

Active/Inactive

Inactive

Decel. Fuel Cut Off

Eng 2, EVAP

Active/Inactive

Inactive

Desired EGR Position

EGR

%

Varies

Desired Idle Speed

Eng 1, Eng 2, CC, EVAP, TAC

0-7,000 RPM

800-950 RPM

Desired Torque ABS/TCS

Eng 2, CC

%

Varies

Distance Since DTC Cleared

Eng 2

km - miles

Varies

ECT Sensor

Eng 1, EVAP, HO2S, Ind, TAC, FF, FR

°C (°F)

Varies

EGR Closed Pintle Position

Ind

%

Varies

EGR Duty Cycle

Ind

%

Varies

EGR Feedback

Eng 1, Ind

Volts

Varies

EGR Flow Test Count

Ind

%

Varies

Engine Load

Eng 1, HO2S, Ign, Ind, MF, FF, FR

0-99%

25-40% - Idle

25-40% - 2500 RPM

Engine Oil Level Switch

Eng 2

Low/OK

OK

Engine Oil Pressure Sensor

Eng 2

Low/OK

OK

Engine Oil Temperature

Eng 1

Temperature

Varies

Engine Run Time

Eng 1, FF, FR

0:00:00

Varies

Engine Speed

All

RPM

750-950 RPM

EVAP Duty Cycle

EVAP

0-100%

Varies

Fan Relay 1 and Relay 2

Eng 2

On, Off

Off

Fuel Level

EVAP

%

Varies

Fuel Level Sensor Left Tank

EVAP

Volts

Varies

Fuel Level Sensor Right Tank

EVAP

Volts

Varies

Fuel Pump

Eng 2, EVAP

On/Off

On

Fuel Tank Level Remaining

EVAP

Liters

Varies

Fuel Tank Pressure Sensor (If Equipped)

EVAP

0-5 Volts

Varies

Fuel Trim Learn

HO2S, Ind

Enabled/Disabled

Enabled

HO2S Sensor 1 and Sensor 2

HO2S, FF, FR

mV

Varies

HO2S Heater Sensor 1 and Sensor 2

HO2S

%

Varies

HO2S Heater Sensor 1 and Sensor 2

HO2S

On/Off

Off

IAT Sensor

Eng 1, EVAP, FT, HO2S, Ind, TAC, FF, FR

-39 to +140°C (-38 to +284°F)

Varies

Ignition 1

ET, Ign

Volts

12.0-14.5 Volts

Ignition Accessory Relay

ET

On/Off

Off

Injector PWM Bank 1

Ign, MF

0-9 ms

4.6-5.4 ms

Knock Detected Cyl. 1-4

Ign, MF

Yes/No

No

Knock Retard

Eng 2, Ign, MF

Degrees

Varies

Long Term FT

Eng 1, HO2S, FT, FF, FR

-100 to +100%

0%

Long Term FT

Ind

Counts

Varies

Low Engine Oil Level Indicator Command

Eng 2

On/Off

Off

Low Fuel Lamp Command (If Equipped)

IPC

On/Off

Off

Low Oil Pressure Warning

Eng 2

On/Off

Off

MAF Sensor

Eng 1, EVAP, HO2S, Ign, Ind, MF

g/s

Varies

Main Relay

ET

On/Off

On

MAP Sensor

Eng 1, Eng 2, Ign

kPa

38-50 kPa

Varies with Altitude

MAP Sensor

Eng 1, Eng 2, HO2S, Ind, MF

0-5 Volts

0.9-1.7 Volts

Mileage at First Failure

Eng 1

km - miles

Varies

Misfire Current Cyl. 1-4

MF

Yes/No

No

Purge Learned Memory B1

EVAP

TBD

TBD

Reduced Engine Power

Eng 1

Active/Inactive

Inactive

Short Term FT

Ind

Counts

Varies

Short Term FT

Eng 1, HO2S, FF, FR

-25 to +25%

-3 to +3%

Spark

Eng 2, Ign, MF, FF, FR

-20 to +40 Degrees

2-10 Degrees

Start Up ECT

Eng 1, EVAP, HO2S, Ind, TAC

-39 to +140°C (-38 to +284°F)

Varies

Starter Relay Status

ET

On/Off

Off

Torque Delivered

Eng 2, CC

%

Varies

Total Knock Retard

Eng 2, Ign, MF

Degrees

Varies

Total Misfire Current Count

MF

Counts

0

TP Angle

FF, FR

%

Varies

TP Indicated Angle

Eng 1, CC, HO2S, Ind, TAC

%

Varies

TP Sensor 1 and Sensor 2

Eng 1, Ind, TAC

volts

Varies

Vehicle Speed Sensor

Eng 1, CC, Ign, Ind, MF, TAC, FF, FR

km/h

mph

0 km/h

(0 mph)