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 normally running engine.

Important: A scan tool that displays faulty data should not be used. The scan tool problem 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 service category Symptoms for diagnosis.

The column labeled Data List indicates where a parameter can be located on the scan tool. Refer to 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
    • 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, 3

On/Off

Off

1-4 Shift Solenoid

Eng 1, 2, 3

Enabled/Disabled

Disabled

A/C Clutch

Eng 1, 2, 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, MF

Yes/No

No

A/C Status

Eng 1, 2, MF

On/Off

Off

AIR Pump Relay

Eng 1, FT

On/Off

Off

AIR Solenoid Relay

Eng 1, FT

On/Off

Off

APP Average

Eng 1, 2, TAC, FT, CC

Counts

Varies

APP Indicated Angle

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

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

Percentage

Varies

APP Sensor 2 Angle

Eng 1, TAC

Percentage

Varies

APP Sensor 3 Angle

Eng 1, TAC

Percentage

Varies

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

Air Fuel Ratio

FR

Ratio

14.0:1

BARO

Eng 1, 3, FT, FF, FR

kPa/Volts

65-104 kPa/3.5-4.5 Volts (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

Clutch Switch

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

Depressed/Released

Released

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 Cruise Disengage History Table

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

Transaxle Gear Position

Varies

Cycles Of Misfire Data

MF

Counts

0-100

Cyl. Mode Misfire Index

MF

Counts

Varies

DTC Set This Ign.

Eng 1, 2, 3, TAC, FT

Yes/No

No

Delivered Torque

Eng 2, 3, TAC

Ft-Lbs/N·m

Varies

Desired Idle

Eng 1, TAC, FF, FR

RPM

PCM Controlled

Desired Torque

Eng 2, 3, TAC, FF, FR

Ft-Lbs/N·m

Varies

Drive 4/OD

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

Drive 4/OD

Drive 4/OD

Drive 3/D

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

Drive 3/D

Drive 3/D

Drive 2

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

Drive 2

Drive 2

Drive 1

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

Drive 1

Drive 1

ECT

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

C°/F°

-39°-140° C (-38°-284° F)

EOP Sensor

Eng 1, 3

Volts

Varies

Engine Load

Eng 1, 3, MF, FR

0-100%

2% @ Idle

9% @ 2500 RPM

Engine Oil Life Remaining

Eng 3

0-100%

Varies

Engine Oil Pressure

Eng 1, 3

kPa/psi

Varies

Engine Run Time

Eng 1, 2

Hrs, Min, Sec

Varies

Engine Speed

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

0-10000 RPM

Varies

EVAP Canister Purge

Eng 1, FT

Percentage

0

EVAP Vacuum Switch

Eng 1, FT

No Purge/Purge

No Purge

Extended Brake Travel Sw.

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

Applied/Released

Released

FC Relay 1

Eng 1, 2

On/Off

Depends on engine temperature and A/C Pressure

FC Relay 2 and 3

Eng 1, 2

On/Off

Depends on engine temperature and A/C Pressure

Fail Counter

FF, FR

Counts

Varies

Fuel Level Sen. Left Tank

Eng 3

5-0 Volts

Varies

Fuel Level Sen. Right Tank

Eng 3

0-5 Volts

Varies

Fuel Tank Level Remaining

Eng 3, FT

0-19 gal./0-72 L

Varies

Fuel Tank Level Remaining

Eng 3, FT

0-100%

Varies

Fuel Tank Rated Capacity

Eng 3, FT

0-19 gal./0-72 L

Varies

Fuel Trim Cell

Eng 1, FT

0-20

Varies

Fuel Trim Diag Inhibited

FT

Enabled/Disabled

Disabled

Fuel Trim Learn

Eng 1, 2, FT

Enabled/Disabled

Enabled (may Toggle)

Generator F Terminal

Eng 3

0-255

Varies

Generator L Terminal

Eng 3

Active/Inactive

Active

HO2S Bnk 1 Sen. 1

Eng 1, FT

Millivolts

10-1000 mV and Varying

HO2S Bnk 1 Sen. 2

Eng 1, FT

Millivolts

10-1000 mV and Varying

HO2S Bnk 2 Sen. 1

Eng 1, FT

Millivolts

10-1000 mV and Varying

HO2S Bnk 2 Sen. 2

Eng 1, FT

Millivolts

10-1000 mV and Varying

IAT

Eng 1, 2, FT

C°/F°

-39°-140° C (-38°-284° F)

IC Ckt Cylinder 1-8

MF

Ok/Fault

Ok

Ignition 1

Eng 1, 2, 3

Volts

0-25

Inj. PWM Average Bank 1

Eng 2, FT, FF, FR

Milliseconds

1-4

Inj. PWM Average Bank 2

Eng 2, FT, FF, FR

Milliseconds

1-4

Knock Retard

Eng 1, FT

0.0°-16°

Varies

Knock Signal Present

Eng 1, 2

Yes/No

No

Long Term FT Avg. Bn 1

FT

Percentage

Varies

Long Term FT Avg. Bn 2

FT

Percentage

Varies

Long Term FT Bn 1

Eng 1, 2, FT, FF, FR

Percentage

Varies

Long Term FT Bn 2

Eng 1, 2, FT, FF, FR

Percentage

Varies

Loop Status

Eng 1, 2, FT MF, FF, FR

Open/Closed

Closed

Low Oil Level

Eng 2, 3

Yes/No

No

MAF

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

kPa/Volts

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

MIL

Eng 1, 2, 3

Off/On

Off

Mileage Since DTC Clear

Eng 2, 3, FF, FR

km/Miles

Varies

Mileage Since First Fail

FR

km/Miles

Varies

Mileage Since Last Fail

FR

km/Miles

Varies

Misfire Cur. 1-8

MF

Counts

Varies

Misfire Failures

MF

Counts

Varies

Misfire Hist. 1-8

MF

Counts

Varies

Misfire Passes

MF

Counts

Varies

Misfiring Cylinder

MF

Prim. Cyl# 0-8

Sec. Cyl# 0-8

0

Misfire Revolution Status

MF

Engine Variables

Accept

PCM Reset

Eng 1, 2, MF

Yes/No

No

PCM in VTD Fail Enable

Eng 3

Yes/No

Varies

PRND A Input

Eng 3

On/Off

Go to DTC P0705 or P0706

PRND B Input

Eng 3

On/Off

Go to DTC P0705 or P0706

PRND C Input

Eng 3

On/Off

Go to DTC P0705 or P0706

PRND P Input

Eng 3

On/Off

Go to DTC P0705 or P0706

PRND Position

Eng 2, 3, CC

Transaxle Gear Selector Position

Go to DTC P0705 or P0706

PT 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, 2, 3, FR

Enable/Disabled

Disabled

Revolutions w/Misfire

MF

Counts

Varies

Short Term FT Avg. Bn 1

FT

Percentage

Varies

Short Term FT Avg. Bn 2

FT

Percentage

Varies

Short Term FT Bn 1

Eng 1, 2, FT, FF, FR

Percentage

Varies

Short Term FT Bn 2

Eng 1, 2, FT, FF, FR

Percentage

Varies

Spark

Eng 1, 2, 3, FT, MF

Degrees

Varies

Start Up ECT

Eng 1, 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, FR

Enabled/Disabled

Disabled

Total Misfire Current Count

MF

Counts

0

Total Misfire Failures Since First Fail

MF

0-65535

0

Total Misfire Passes Since First Fail

MF

0-65535

0

TP Desired Angle

Eng 1, 2, 3, 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

0.25-1.5 V

TP Sensor 2

Eng 1, TAC

Volts

3.0-1.5 V

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

Active/Inactive

Inactive

Transmission OSS

FR

RPM

Varies

Transmission Range

Eng 1, 2, 3, CC

Transaxle Gear Position

Varies

Vehicle Speed

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

km/h/mph

Varies

VTD Auto Learn Timer

Eng 3

Active/Inactive

Inactive

VTD Fuel Disable

Eng 3, FF, FR

Active/Inactive

Inactive

VTD Fuel Disable Until Ign. Off

Eng 3

Yes/No

No

Warm Up Cycles w/o Emis. Faults

Eng 2

Counts

0-255

Warm Up Cycle w/o Non-Emis. Faults

Eng 2

Counts

0-255