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For 1990-2009 cars only

Scan Tool Data List Except Holden

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 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. If all values are within the typical range described below, refer to Testing for Intermittent Conditions and Poor Connections 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.

Eng: Engine Data

EGR: EGR Data

EVAP: EVAP Data

FT: Fuel Trim Data

HO2S: O2S/HO2S Data

MF: Misfire Data

CH: Cooling/HVAC Data

IPC: IPC Data

FF: Freeze Frame Data

FR: Failure Records Data

Scan Tool 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

5 Volt Reference 1

EGR, EVAP, CH

0-5 Volts

5.0 Volts

A/C High Side Pressure Sensor

CH

0-5 Volts

Varies

A/C High Side Pressure Sensor

CH

kPa/psi

Varies

A/C Relay Command

Eng, EGR, MF, CH

On/Off

Off

A/C Request Signal

CH

Yes/No

No

Air Flow Calculated

Eng , FT, HO2S, MF, FF, FR

g/s

3-6 g/s

Air Fuel Ratio

Eng, FT, HO2S, FF, FR

Ratio

14.7:1

BARO

Eng , EGR, EVAP, HO2S, FT, FF, FR, MF

65-104 kPa

Varies with altitude

Catalytic Converter Protection Active

HO2S, FT, MF

Yes/No

No

CMP Active Counter

Eng, MF

1-3 Counts

Varies

Coolant Hot Lamp (If Equipped)

IPC

On/Off

Off

Decel. Fuel Cutoff

EGR, FT, HO2S

Active/Inactive

Inactive

Desired EGR Position

EGR

%

Varies

Desired IAC Position

Eng

Counts

Varies

Desired Idle Speed

Eng, EVAP, FF, FR

0-7,000 RPM

800-950 RPM

ECT Sensor

Eng , EGR, EVAP, FT, HO2S, MF, CH, IPC, FF, FR

-39°C to +140°C (-38°F to +284°F)

Varies

EGR Flow Test Count

EGR

Counts

Varies

EGR Learned Minimum

EGR

Volts

Varies

EGR Position Sensor

Eng, EGR, FT, MF

%

Varies

EGR Position Sensor

EGR

Volts

Varies

EGR Position Variance

EGR

Counts

Varies

EGR Solenoid Command

EGR

%

Varies

Engine Load

Eng , EGR, EVAP, FT, HO2S, MF, CH, FF, FR

0-99%

25-40% - Idle

25-40% - 2500 RPM

Engine Run Time

ALL

0:00:00

Varies

Engine Speed

ALL

RPM

750-950 RPM

EVAP Purge Solenoid Command (If Equipped)

Eng, EVAP, FT, HO2S

0-100%

Varies

EVAP Vent Solenoid Command (If Equipped)

Eng, EVAP

Venting/Not Venting

Venting

Fail Counter

FF, FR

Counts

Varies

Fans High Speed

CH

ON/OFF

Varies

Fans Low Speed

CH

ON/OFF

Varies

Fuel Level to Cluster

EVAP, IPC

%

Varies

Fuel Level Sensor

Eng, EVAP, FT, IPC

0-5 Volts

Varies

Fuel Level Sensor

Eng, EVAP, FT, IPC

%

Varies

Fuel Pump Relay Command

Eng, FT

On/Off

On

Fuel Tank Pressure Sensor (If Equipped)

Eng, EVAP

in H2O/mm Hg

Varies

Fuel Tank Pressure Sensor (If Equipped)

Eng, EVAP, FF, FR

0-5 Volts

Varies

Fuel Trim Cell

Eng, FT, FF, FR

Cell Number

20

Fuel Trim Learn

Eng, FT, FF, FR

Enabled/Disabled

Enabled

O2S/HO2S 1

Eng, EVAP, FT, HO2S, FF, FR

0-1,006 mV

Varies 400-800 mV

O2S/HO2S 1 Ready

HO2S

Yes/No

Yes

O2S/HO2S 2

Eng, EVAP, FT, HO2S, FF, FR

0-1,006 mV

Varies 400-800 mV

IAC Position

Eng, EGR, FT, HO2S, CH, FF, FR

Counts

15-40 Counts

IAT Sensor

Eng, EGR, EVAP, FT, HO2S, MF, CH, FF, FR

-39° to +140°C (-38° to +284°F)

Varies

Ignition 1 Signal

Eng, EGR, EVAP, FT, HO2S, MF, CH, IPC

Volts

12.0-14.5 Volts

IMT Valve Command (If Equipped)

Eng

On/Off

Off

Injector PWM

Eng, FT, HO2S, MF, FF, FR

0-9 ms

4.6-5.4 ms

Knock Retard

Eng, EGR, CH

Degrees

Varies

KS Active Counter

Eng

Counts

Varies

Long Term FT

Eng, EVAP, FT, HO2S, FT, FF, FR

-100% to +100%

0%

Long Term FT Avg.

FT

-100% to +100%

0%

Loop Status

Eng, EVAP, FT, HO2S, FF, FR

Open Loop/Closed Loop

Closed Loop

Low Fuel Lamp Command (If Equipped)

IPC

On/Off

Off

MAP Sensor

Eng, EGR, EVAP, FT, HO2S, MF, FF, FR

kPa

38-50 kPa

Varies with Altitude

MAP Sensor

Eng, MF, FF, FR

0-5 Volts

0.9-1.7 Volts

MIL Command

Eng, IPC

On/Off

Off

Mileage Since First Failure

FF, FR

km - miles

Varies

Mileage Since Last Failure

FF, FR

km - miles

Varies

Misfire Current Cyl. 1-4

MF

0-255 Counts

0

Misfire History Cyl. 1-4

MF

0-65,535 Counts

0

Not Run Counter

FF, FR

Counts

Varies

Pass Counter

FF, FR

Counts

Varies

PNP Switch

Eng, EGR, IPC

Park/Neutral/In Gear

Park/Neutral

Power Enrichment

FT, HO2S, MF, FF, FR

Active/Inactive

Inactive

Power Steering Switch (If Equipped)

Eng, CH

High Pressure/Normal Pressure

Normal Pressure

Rich/Lean to Lean/Rich Ratio Sensor 1

FT, HO2S

Counts

Varies

Rich/Lean Transition Sensor 1

FT, HO2S

Counts

Varies

Rough Road Sensor (If Equipped)

MF

0-5 Volts

2-3 Volts

Short Term FT Avg.

FT

-25% to +25%

-3% to +3%

Short Term FT

Eng, EVAP, FT, HO2S, FF, FR

-25% to +25%

-3% to +3%

Spark

Eng, FT, HO2S, MF, CH

-20 to +40 Degrees

2-10 Degrees

Start Up ECT

EVAP, HO2S, CH, FF, FR

-39° to +140°C (-38° to +284°F)

Varies

Start Up IAT

EVAP, HO2S, CH, FF, FR

-39° to +140°C (-38° to +284°F)

Varies

SVS Lamp Command (If Equipped)

IPC

On/Off

Off

TCC Enable Solenoid Command (If Equipped)

Eng, MF

On/Off

Off

Total Fuel Trim Average

EVAP, FT, HO2S

-100 to +100%

Varies

Total Misfire

MF

Counts

0

TP Sensor

Eng, EGR, EVAP, FT, HO2S, MF, FF, FR

0-5 Volts

0.0-0.3 Volts

TP Sensor

Eng, EGR, EVAP, FT, HO2S, MF, FF, FR

%

5-15 %

TWC Temperature Calculated

MF

Temperature

Varies

Vehicle Security Status (If Equipped)

Eng, IPC

Enabled/Disabled

Disabled

Vehicle Speed Sensor

Eng, EGR, EVAP, FT, HO2S, MF, CH, IPC, FF, FR

Km/h

mph

0 km/h

(0 mph)

Scan Tool Data List Holden

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 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 under the conditions specified in the first row of the Scan Tool Data List table.

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. If all values are within the typical range described below, refer to Testing for Intermittent Conditions and Poor Connections for diagnosis.

Scan Tool Data List

Scan Tool Parameter

System State

Expected Value

Description

Engine Idling / Operating Temperature / Closed Throttle / Park or Neutral / Closed Loop / Accessories Off

5V Reference Voltage

-

Voltage

This parameter displays the diagnostic state of the output driver for the 5 volt reference circuit.

A/C Clutch (Air Conditioning)

On

Off

-

This parameter displays the state of the air conditioning (A/C) clutch relay control circuit as commanded by the control module.

A/C Pressure (Air Conditioning)

-

Voltage

This parameter displays the voltage from the A/C high side pressure sensor signal circuit to the control module.

A/C Request (Air Conditioning)

No

Yes

-

This parameter displays the state of the A/C request input to the control module from the heating, ventilation, and air conditioning (HVAC) controls.

Air/Fuel Ratio

-

14.6:1

This parameter displays the ratio of air to fuel as calculated by the control module based on various sensor inputs.

B1 LTFT Average (Bank 1 Long Term Fuel Trim)

-

%

This parameter displays the commanded Long Term Fuel Trim correction by the control module for bank 1 for cruise and acceleration conditions.

B1 STFT Average (Bank 1 Short Term Fuel Trim)

-

%

This parameter displays the short-term correction to the fuel delivery by the control module in response to oxygen sensor 1.

B1S1 O2 Sensor Ready (Bank 1 Sensor 1)

No

Yes

-

This parameter displays that the HO2S 1 is at operating temperature.

B1S1 O2 Sensor Rich/Lean to Lean/Rich Response Ratio (Bank 1 Sensor 1)

-

1:1

This parameter displays the lambda output from the HO2S to the control module. A lambda below 1.0 indicates a rich exhaust, while a lambda above 1.0 indicates a lean exhaust.

B1S1 O2S Rich/Lean Switches (Bank 1 Sensor 1)

-

Counts

This parameter displays the oxygen sensor rich/lean and lean/rich switches.

Barometric Pressure

kPa

102

This parameter displays the barometric pressure. The control module uses the barometric pressure sensor input for fuel control to compensate for altitude differences.

Battery Voltage

-

Battery Voltage

The scan tool displays the voltage measured between the module’s battery positive voltage circuit and ground circuit.

Calculated Airflow

-

g/s

This parameter displays the calculated air flow into the engine that is based on manifold absolute pressure. The calculation is used in several diagnostics to determine when to run the diagnostics.

Calculated Catalyst Temperature

-

°C

This parameter displays the catalytic converter temperature as calculated by the control module

Camshaft Active Counter

-

Counts

This parameter displays the CMP active counts.

Catalyst Protection Mode

Inactive

Active

-

This parameter displays if the control module is commanding catalytic converter protection.

Closed Loop

Yes

No

-

This parameter displays the Closed Loop Active (Yes) or Inactive (No).

Coolant Temperature

-

°C

This parameter displays the temperature of the engine coolant based on input to the control module from the engine coolant temperature (ECT) sensor.

Cooling Fan High Speed

On

Off

-

This parameter displays the control module commanded state of the fan relay control circuit.

Cooling Fan Low Speed

On

Off

Deceleration Fuel Cutoff

Inactive

Active

-

This parameter displays the status of the operating mode of the control module used to turn off the fuel injectors during certain deceleration conditions.

Desired EGR Position

-

%

This parameter displays the desired EGR position as commanded by the control module.

Desired Engine Idle Speed

-

RPM

This parameter displays the desired engine idle speed as commanded by the control module.

Desired IAC Position (Idle Air Control)

-

Steps

This parameter displays the desired IAC position as commanded by the control module.

EGR Duty Cycle

-

%

This parameter displays the EGR pintle position in percent of range as commanded by the control module.

EGR Feedback

-

V

This parameter displays the actual EGR pintle position in volts.

EGR Flow Test Count (Exhaust Gas Recirculation)

-

Counts

This parameter displays the number of EGR flow test samples collected during the current ignition cycle.

EGR Learned Minimum Position (Exhaust Gas Recirculation)

-

V

This parameter displays the learned minimum value of the EGR valve as recorded by the control module during the last learn procedure.

EGR Position Sensor

-

%

This parameter displays the EGR pintle position in percent of range as commanded by the control module.

EGR Position Variance (Exhaust Gas Recirculation)

-

Counts

This parameter displays the difference between the actual command of the EGR valve to the desired position of the EGR valve.

Engine Load

-

%

This parameter displays the calculated engine load in percent based on inputs to the control module from various engine sensors.

Engine Runtime

-

h:m:s

This parameter displays the time elapsed since the engine was started.

Engine Speed

-

RPM

This parameter displays the speed of the engine crankshaft rotation from information received from the crankshaft position (CKP) sensor.

Fuel Level Input

-

V

This parameter displays the voltage signal received by the control module from the fuel level sensor.

Fuel Level Output

-

%

Sensor: This parameter displays the percentage signal received by the control module from the fuel level sensor.

Fuel Pump

On

Off

-

This parameter displays the control modules commanded state of the fuel pump relay control circuit.

Fuel Trim Cell

-

Counts

This parameter displays what fuel trim cell that is currently active.

Fuel Trim Learn

Yes

No

-

This parameter displays Yes when conditions are appropriate for enabling long term fuel trim corrections.

Heated O2 Sensor

-

mV

This parameter displays the voltage output from the HO2S to the control module.

Hot Mode Lamp

On

Off

-

This parameter displays the Hot Mode Lamp Active (On) or Inactive (Off).

Idle Air Control

-

Steps

This parameter displays the ECM command for the idle air control (IAC) pintle position in steps.

Injector PWM Average

-

ms

This parameter displays the average pulse width of the fuel injectors as determined by the control module.

Intake Air Temperature

-

°C

This parameter displays the temperature of the air entering the air induction system based on input to the control module from the intake air temperature (IAT) sensor.

Knock Retard

-

°CA

This parameter indicates the amount of spark advance the control module removes from the ignition control (IC) spark advance in response to the signal from the knock sensors.

Knock Sensor Active Counter

-

Counts

This parameters displays the number of times the control module detects activity from the knock sensor.

Long Term Fuel Trim

-

%

This parameter displays the commanded Long Term Fuel Trim correction by the control module.

Low Fuel Lamp

On

Off

-

This parameter displays the control modules commanded state of the low fuel lamp.

Manifold Absolute Pressure

-

kPa

This parameter displays the pressure from the manifold absolute pressure (MAP) sensor to the control module.

MIL Request

On

Off

-

This parameter displays the commanded state of the malfunction indicator lamp (MIL) control circuit by the control module.

Misfire Current Cyl. #1

-

Counts

This parameter displays the number of misfires that have been detected during the last 200 cylinder firing events.

Misfire Current Cyl. #2

Misfire Current Cyl. #3

Misfire Current Cyl. #4

Misfire History Cyl. #1

-

Counts

The misfire history counters display the total level of misfire that has been detected on each cylinder.

Misfire History Cyl. #2

Misfire History Cyl. #3

Misfire History Cyl. #4

O2 Sensor

-

mV

This parameter displays the voltage output from the HO2S to the control module.

Park/Neutral Switch

P

N

R

1,2,3,4

P/N

This parameter displays whether the transmission range selector is in park/neutral or in gear.

Power Enrichment

Inactive

Active

-

This parameter displays the status of the operating mode of the control module used to increase fuel delivery during certain acceleration conditions.

Power Steering Switch

On

Off

-

This parameter displays the state of the power steering pressure switch.

Purge Solenoid

-

%

This parameter displays the percentage of Purge at the Purge Solenoid.

Rough Road Sensor

-

V

This parameter displays the voltage from the rough road sensor.

Short Term Fuel Trim

-

%

This parameter displays percentage. This parameter indicates the average of the short term fuel trim cells The short fuel trim cells are rated, or weighted for the amount of which they are used.

Spark Advance

-

°CA

This parameter displays the amount of spark advance the control module is commanding on the ignition control circuits.

Start Up ECT (Engine Coolant Temperature)

-

°C

This parameter displays the temperature of the engine coolant on start up based on input to the control module from the ECT sensor.

Start Up IAT (Intake Air Temperature)

-

°C

This parameter displays the temperature of the intake air at start in the air induction system based on input to the control module from the IAT sensor.

SVS Lamp (Service Vehicle Soon)

On

Off

-

This parameter displays the control modules commanded state of the service vehicle soon lamp.

TCC Engaged

No

Yes

-

This parameter displays the control module commanded state of the TCC solenoid.

Throttle Position Sensor

-

V

This parameter displays the actual voltage on the TP sensor signal circuit as measured by the control module.

Throttle Position Sensor Signal

-

%

This parameter displays the percent of throttle opening as calculated by the control module using information from the TP sensor.

Total Misfire

-

Counts

This parameter displays the total number of cylinder firing events that the control module detected as misfires for the last 200 crankshaft revolution sample period.

Vehicle Speed

-

km/h

This parameter displays the speed of the vehicle. received from the vehicle speed sensor (VSS).

Vehicle Theft Deterrent

Disabled

Enabled

-

This parameter displays the status of the vehicle theft deterrent system.

VGIS Enable

Disabled

Enabled

-

This parameter displays the control modules commanded state of the VGIS (Variable Geometry Induction System) solenoid.