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 given 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 is determined:

    • Powertrain On-Board Diagnostic System Check is completed.
    • No Diagnostic Trouble Codes (DTCs).
    • 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 values that would be seen on a normal running engine.

Important: A scan tool that displays faulty data should not be used. The scan tool concern should be reported to the manufacturer. Use of a faulty scan tool can result in misdiagnosis and 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 for diagnosis.

The column labeled Data List indicates where a parameter can be 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 List

Eng 2: Engine Data 2 List

Eng 3: Engine Data 3 List

CC: Cruise Control Data

EE: Enhanced EVAP Data

FF/FR: Freeze Frame/Failure Records

FT: Fuel Trim Data List

MF: Misfire Data List

TAC: TAC Data List

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

Scan Tool Parameter

Data List

Parameter Range/Units

Typical Data Values

1-4 Shift Lamp

Eng 1, 2,

On/Off

Off

1-4 Shift Solenoid

Eng 1, 2,

Enabled/Disabled

Disabled

A/C Relay Command

Eng 1, 2, EE, MF

On/Off

Off

A/C High Side Pressure

Eng 2

Volts

Varies

A/C High Side Pressure

Eng 2

kPa/psi

Varies

A/C Request

Eng 1, 2, EE, MF

Yes/No

No

A/C Status

Eng 1, 2, EE, MF

On/Off

Off

Air Fuel Ratio

FF, FR

Ratio

14.7:1

AIR Pump Relay

Eng 1, FT

On/Off

Off

AIR Solenoid Valve

Eng 1, FT

On/Off

Off

APP Average

Eng 1, 2, TAC, FT, CC, FF, FR

Counts

Varies

APP Indicated Angle

All

Percentage

Varies

APP Sensor 1

Eng 1, TAC

Volts

0.25-1.1V

APP Sensor 2

Eng 1, TAC

Volts

3.9-4.8

APP Sensor 3

Eng 1, TAC

Volts

3.2-4.5

APP Sensor 1 Angle

Eng 1, TAC

0-100%

0%

APP Sensor 2 Angle

Eng 1, TAC

0-100%

0%

APP Sensor 3 Angle

Eng 1, TAC

0-100%

0%

APP Sensor 1 Out of Range

TAC

Yes/No

No

APP Sensor 2 Out of Range

TAC

Yes/No

No

APP Sensor 3 Out of Range

TAC

Yes/No

No

APP Sen 1 and APP Sen 2 Disagree

TAC

Yes/No

No

APP Sen 1 and APP Sen 3 Disagree

TAC

Yes/No

No

APP Sen 2 and APP Sen 3 Disagree

TAC

Yes/No

No

BARO

Eng 1, 3, FT, FF, FR

kPa/Volts

65-104 kPa/3.5-4.9V (Varies w/Altitude)

CAM Signal Input High to Low

Eng 1, 3

Counts

Varies

CAM Signal Input Low to High

Eng 1, 3

Counts

Varies

CC Brake Switch

(Manual Transmission Only)

Eng 1, 3, TAC, CC

Applied/Released

Released

Clutch Switch

(Manual Transmission Only)

Eng 1, 2, TAC, CC, FF, FR

Depressed/Released

Released

Cold Start Up

Eng 1, 2, EE

Yes/No

Varies

Column Lock Fuel Disable-ABS DTC

Eng 2, 3

Yes/No

No

Column Lock PCM-BCM Com.

Eng 2, 3

Fault/OK

OK

Column Lock Fuel Disable-BCM DTC

Eng 2, 3

Yes/No

No

Cruise Disengage History 1-8

CC

Go to Diagnostic System Check - Cruise Control in Cruise Control

Varies

Cruise Requested

Eng 1, 3, TAC, CC

Yes/No

No

Cruise Resume/Accel

Eng 1, TAC, CC

On/Off

Off

Cruise Set/Coast

Eng 1, TAC, CC

On/Off

Off

Cruise Switch

Eng 1, TAC, CC

On/Off

Off

Current Gear

Eng 2, 3, FF, FR

1-4

1

Cycles Of Misfire Data

MF

Counts

0-100

Cyl. Mode Misfire Index

MF

Counts

Varies

DTC Set This Ignition

Eng 1, 2, 3, EE, TAC, FT

Yes/No

No

Delivered Torque

Eng 2, 3, TAC

N·m/Ft-Lbs

Varies

Desired Idle Speed

Eng 1, TAC, FF, FR

RPM

PCM Controlled

Desired Torque

Eng 2, 3, TAC

N·m/Ft-Lbs

Varies

ECT

Eng 1, 2, 3, FT, MF, FF, FR, EE

-39° to 140°C (-38° to 284°F)

90° to 110°C (194° to 230°F)

Engine Load

Eng 1, 3, MF, FF, FR

0-100%

2% @ Idle

9% @ 2500 RPM

Engine Oil Life Remaining

Eng 3

0-100%

Varies

Engine Oil Pressure/EOP

Eng 1, 3

kPa/psi/Volts

Varies

Engine Run Time

Eng 1, 2, EE, FF, FR

Hrs, Min, Sec

Varies

Engine Speed

All

0-10,000 RPM

Varies

EVAP Canister Purge

Eng 1, EE, FT

Percentage

Varies

EVAP Canister Vent Valve

Eng 1, EE

Venting/Not Venting

Varies

Extended Brake Travel Sw.

Eng 1, 2, 3, TAC, CC, FF, FR

Applied/Released

Released

FC Relay 1

Eng 1, 2, EE

On/Off

Depends on engine temperature and A/C Pressure

FC Relay 2 and 3

Eng 1, 2, EE

On/Off

Depends on engine temperature and A/C Pressure

Fail Counter

FR

Counts

Varies

Fuel Level Sen. Left Tank

Eng 3, EE

5-0V

0.7-2.5 Volts

Fuel Level Sen. Right Tank

Eng 3, EE

5-0V

0.7-2.5 Volts

Fuel Tank Level Remaining

Eng 3, FT, EE

0-19 gal./0-73L

Varies

Fuel Tank Level Remaining

Eng 3, FT, EE

0-100%

Varies

Fuel Tank Pressure

Eng 1, EE

-32.7 to 14.0 mm/Hg

-17.5 to 7.5 in/H2O

Varies

Fuel Tank Pressure

EE

0-5 Volts

Varies

Fuel Tank Rated Capacity

Eng 3, FT, EE

73L (19 gal.)

73L (19 gal.)

Fuel Trim Cell

Eng 1, FT

0-23

Varies

F.T Diag Inhibited

FT

Enabled/Disabled

Disabled

Fuel Trim Learn

Eng 1, 2, EE, FT

Enabled/Disabled

Enabled (may Toggle)

Generator F Terminal

Eng 3

0-100%

Varies

Generator L Terminal

Eng 3

Active/Inactive

Active

HO2S Bank 1 Sensor 1

Eng 1, FT

Millivolts

10-1,000 mV and Varying

HO2S Bank 1 Sensor 2

Eng 1, FT

Millivolts

10-1,000 mV and Varying

HO2S Bank 2 Sensor 1

Eng 1, FT

Millivolts

10-1,000 mV and Varying

HO2S Bank 2 Sensor 2

Eng 1, FT

Millivolts

10-1,000 mV and Varying

IAT

Eng 1, 2, EE, FT

-39° to 140°C (-38° to 284°F)

Varies

IC Circuit Cylinder 1-8

MF

Ok/Fault

Ok

Ignition 1

Eng 1, 2, 3, EE

0-25 Volts

11.5-14.5

Inj. PWM Average Bank 1

Eng 2, EE, FT, FF, FR

Milliseconds

1-4

Inj. PWM Average Bank 2

Eng 2, EE, FT, FF, FR

Milliseconds

1-4

Knock Retard

Eng 1, FT

0°-16°

Varies

Long FT1 Average

FT

Percentage

Near 0%

Long FT2 Average

FT

Percentage

Near 0%

Long Term FT Bank 1

Eng 1, 2, EE, FT, FF, FR

Percentage

Near 0%

Long Term FT Bank 2

Eng 1, 2, EE, FT, FF, FR

Percentage

Near 0%

Loop Status

Eng 1, 2, EE, FT MF, FF, FR

Open/Closed

Closed

Low Oil Level

Eng 2, 3

Yes/No

No

MAF

Eng 1, 2, 3, EE, TAC, FT, MF, FF, FR

Grams Per Seconds (g/s)

5-9 @ Idle (depends on altitude)

20-26 @ 2500 RPM (depends on altitude)

MAF Frequency

Eng 2

0-31,999Hz

Varies

MAP

Eng 1, 2, 3, EE, TAC, FT, FF, FR

kPa/Volts

20-48 kPa/1.0-2.0V (varies w/altitude)

MIL

Eng 1, 2, 3, EE

Off/On

Off

Mileage Since DTC Cleared

Eng 2, 3

km/Miles

Varies

Mileage Since MIL Request

FF

km/Miles

Varies

Mileage Since First Fail

FF, FR

km/Miles

0

Mileage Since Last Fail

FR

km/Miles

0

Misfire Current 1-8

MF

0-200

0

Misfire History 1-8

MF

0-65,535

0

Misfiring Cylinder

MF, FF, FR

Prim. Cyl# 0-8

Sec. Cyl# 0-8

00000000 Prim.

00000000 Sec.

Misfire Revolution Status

MF

Reject/Accept

Accept

Not Run Counter

FR

Counts

Varies

Pass Counter

FR

Counts

Varies

PCM Reset

Eng 1, 2, MF

Yes/No

No

PCM/VCM in VTD Fail Enable

Eng 3

Yes/No

No

PRND A Input

Eng 3

On/Off

On

PRND B Input

Eng 3

On/Off

Off

PRND C Input

Eng 3

On/Off

Off

PRND P Input

Eng 3

On/Off

On

PRND Position

Eng 2, 3, CC

Transaxle Gear Selector Position

Park

Powertrain Induced Chassis Pitch

Eng 1, 2, FF, FR

Active/Inactive

Inactive

Reduced Engine Power

Eng 1, 2, 3, TAC, FT, CC

Active/Inactive

Inactive

Reverse Inhibit

Eng 1

Yes/No

No

Revolutions w/Misfire

MF

Counts

0

SHRT FT1 Average

FT

Percentage

Near 0%

SHRT FT2 Average

FT

Percentage

Near 0%

Short Term FT Bank 1

Eng 1, 2, EE, FT, FF, FR

Percentage

Near 0%

Short Term FT Bank 2

Eng 1, 2, EE, FT, FF, FR

Percentage

Near 0%

Spark

Eng 1, 2, 3, EE, FT, MF

Degrees

Varies

Start Up ECT

Eng 1, EE, FF, FR

C°/F°

Varies

Stop Lamp Switch

Eng 1, 3, TAC, CC

Applied/Released

Released

TAC/PCM Communication

Eng 1, 3, TAC, CC

OK/Fault

OK

TCC/CC Brake Switch

Eng 1, 2, 3, TAC, CC, FF, FR

Applied/Released

Released

TCC Duty Cycle

Eng 1, 2, MF, FF, FR

Disabled/Enabled

Disabled

TCC Enable Solenoid

Eng 1, 2, MF, CC, TAC, FF, FR

Enabled/Disabled

Disabled

Total Misfire Current Count

MF

Counts

0

Total Misfire Failures Since First Fail

MF

0-65,535

0

Total Misfire Passes Since First Fail

MF

0-65,535

0

TP Desired Angle

Eng 1, 2, 3, EE, TAC, FT, CC, FF, FR

Percentage

3-10%

TP Indicated Angle

All

Percentage

3-9%

TP Sensor 1 Angle

Eng 1, TAC

Percentage

Varies

TP Sensor 2 Angle

Eng 1, TAC

Percentage

Varies

TP Sensor 1

Eng 1, TAC

Volts

0.25-1.5V

TP Sensor 2

Eng 1, TAC

Volts

4.0-1.5V

TP Sensors Disagree

TAC

Yes/No

No

TP Sensor 1 Out of Range

TAC

Yes/No

No

TP Sensor 2 Out of Range

TAC

Yes/No

No

Traction Control

Eng 1, 3, TAC, CC, FF, FR

Active/Inactive

Inactive

Transmission Fluid Temp.

(Export-manual transmission only)

FF, FR

C°/F°

Varies

Transmission OSS

FF, FR

RPM

Varies

Transmission Range

Eng 1, 2, 3, CC, FF, FR

Transaxle Gear Position

Park/Neutral

Vehicle Speed

ENG 1, 2, 3, EE, TAC, FT, CC, FF, FR

km/h/mph

0 km/h (0 mph)

VTD Auto Learn Timer

Eng 3

Active/Inactive

Inactive

VTD Fuel Disable

Eng 3

Active/Inactive

Inactive

VTD Fuel Disable Until Ign. Off

Eng 3

Yes/No

No

Warm-Ups w/o Emis. Faults

Eng 2

Counts

0-255

Warm-Ups w/o Non-Emis. Faults

Eng 2

Counts

0-255