GM Service Manual Online
For 1990-2009 cars only
Table 1: Engine 1 Data List
Table 2: Engine 2 Data List
Table 3: Engine 3 Data List
Table 4: Engine 4 Data List

Use the scan tool data listed in this table for comparison after the On-Board Diagnostic system check and finding the on-board diagnostics function properly with no diagnostic codes displayed.

The Typical Scan Tool Data Values are an average of display values recorded from normally operating vehicles. The Typical Scan Tool Data Values are intended to represent what a normally functioning system would display. The values you get may vary due to a low battery charge or other reasons. But they should be very close.

Do not use a scan tool that displays faulty data. Report the problem to the manufacturer. The use of a faulty scan tool can result in misdiagnosis and unnecessary parts replacement.

Use only the parameters listed in the tables for diagnosis. If a scan tool reads other parameters, the values are not recommended by General Motors for use in diagnosis. For more description on the values and the use of the scan tool diagnosis the VCM inputs, refer to the applicable diagnosis. If all values are within the range illustrated, refer to Driveability Symptoms.

Engine 1 Data List

Engine at Operating Temperature/Engine Idling in Closed Loop/ Closed Throttle/ Park or Neutral/ Acc. OFF

Scan Position

Units Displayed

Typical Data Value

Engine Speed

RPM

650 RPM

Desired Speed

RPM

652 RPM

ECT

°C/°F

93°C (200°F)

Startup ECT

°C/°F

Varies

ECT Sensor

Volts

2.00 Volts

IAT Sensor

Volts

1.46 Volts

IAT Sensor

°C/°F

43°C (109°F)

Air to Fuel Ratio

Ratio

14.7:1

MAP Sensor

Volts

1.46 Volts

BARO Sensor

Volts

4.76 Volts

MAP

kPa

38 kPa

BARO

kPa

101 kPa

TP Sensor

Volts

0.44-0.68 Volts

TP Angle

%

0 %

Long Term FT Bn 1

%/Counts

0%/126

Long Term FT Bn 2

%/Counts

0%/126

Short Term FT Bn 1

%/Counts

0%/0.0

Short Term FT Bn 2

%/Counts

0%/0.0

Fuel Trim Cell Bn 1

Counts

17

Fuel Trim Cell Bn 2

Counts

17

IAC Position

Counts

18

Desired IAC

Counts

18

KS Activity

Yes/No

No

Knock Sensor

Volts

4.8 volts

Spark Advance

Degrees

21°

Knock Retard

Degrees

0°-2°

Cam Retard

Degrees

0°-2°

Engine Speed

RPM

650 RPM

Engine Load

%

5%

MAF Sensor

g/s

5-7 g/s

DTC Counts

Counts

0

Engine Run Time

Min/Sec

Varies

Engine 2 Data List

Engine at Operating Temperature/Engine Idling in Closed Loop/ Closed Throttle/ Park or Neutral/ Acc. OFF

Scan Position

Units Displayed

Typical Data Value

Engine Speed

RPM

650 RPM

Desired Idle

RPM

652 RPM

IAC Position

Counts

18

Desired IAC

Counts

18

Front HO2S

Ready/Not Ready

Ready

Rear HO2S

Ready/Not Ready

Ready

HO2S Bn 1 Sen 1

mV

65-840 mV

HO2S Bn 2 Sen 1

mV

130-870 mV

HO2S Bn 1 Sen 2

mV

65-840 mV

HO2S Bn 1 Sen 3

mV

130-870 mV

HO2S X Counts Bn 1

mV

Varies

HO2S X Counts Bn 2

mV

Varies

Long Term FT Bn 1

%/Counts

0 %/126

Long Term FT Bn 2

%/Counts

0 %/126

Short Term FT Bn 1

%/Counts

0 %/0.0

Short Term FT Bn 2

%/Counts

0 %/0.0

Fuel Term FT Bn 1

Counts

17

Fuel Term FT Bn 2

Counts

17

Rich/Lean Bn 1

Rich/Lean

Varies

Rich/Lean Bn 2

Rich/Lean

Varies

Loop Status

Open/Closed

Closed

CL Since Restart

Yes/No

Yes

ECT

°C/°F

Varies

Startup ECT

°C/°F

Varies

Ignition 1

Volts

Varies

Air to Fuel Ratio

Ratio

14.7: 1

MAF

g/s

5-7 g/s

Long Term FT

Disabled

126

DTC Counter

Counts

0

Engine Run Time

Min/Sec

Varies

Engine 3 Data List

Engine at Operating Temperature/Engine Idling in Closed Loop/ Closed Throttle/ Park or Neutral/ Acc. OFF

Scan Position

Units Displayed

Typical Data Value

Engine Speed

RPM

650 RPM

Desired Idle

RPM

652 RPM

EVAP Duty Cycle

%

0 %

Air to Fuel Ratio

Ratio

14.7:1

EVAP Canister

On/Off

Off

EVAP Vacuum Switch

Not Available

--

EGR Duty Cycle

%

0 %

Actual EGR Position

%

0 %

Desired EGR Position

%

0.0 %

EGR Sensor

Volts

0.82 Volts

IAC Position

Counts

18

Desired IAC

Counts

18

ECT

°C/°F

Varies

Startup ECT

°C/°F

Varies

Ignition 1

Volts

Varies

IAT

°C/°F

Varies

Trans. Range

Current Gear

P/N

A/B/C/ Range

On/Off

On/On/On

Cruise Mode

Yes/No

No

TCC Enable

Yes/No

No

MPH Km/h

MPH Km/h

0 MPH Km/h

TCC Enable

Yes/No

No

TCC Duty Cycle

%

0 %

TCC Slip Speed

RPM

0 RPM

1/2 Sol 2/3 Sol

0n/Off

On/Off

Off

Off

3-2 Down Shift

Yes/No

No

Brake Switch

Open/Closed

Open

Decel Fuel Mode

Yes/No

No

Spark Control

Advance/Retard

Advance

Cam Retard

Degrees

0°±20°

4WD

Yes/No

No

4WD Low

Yes/No

No

Ignition 1 On

Yes/No

Yes

Ignition 1 Low

Yes/No

No

Ignition 1 High

Yes/No

No

Power Enrichment

Yes/No

No

A/C Status

Yes/No

No

A/C Request

Yes/No

No

A/C Relay

On/Off

Off

A/C Engaged

Yes/No

No

DTC Counter

Counts

0

Engine Run Time

Min/Sec

Varies

Engine 4 Data List

Engine at Operating Temperature/Engine Idling in Closed Loop/ Closed Throttle/ Park or Neutral/ Acc. OFF

Scan Position

Units Displayed

Typical Data Value

Engine Speed

RPM

650 RPM

Desired Idle

RPM

652 RPM

IAC Position

Counts

18

Desired IAC

Counts

18

KS Adjust Factor

Degrees

KS Activity

Yes/No

No

Inj. Ave. Bn 1

ms

3.5 ms

Inj. Ave. Bn 2

ms

3.5 ms

Engine Load

%

5 %

MAF

g/s

5-7 g/s

TP Sensor

Volts

0.45-0.85 Volts

TP Angle

%

0 %

MAP Sensor

Volts

1.2 Volts

BARO

Volts

3.00 Volts

MAP

kPa

33 kPa

BARO

kPa

76 kPa

EVAP Duty Cycle

%

0 %

EGR Duty Cycle

%

0 %

Actual EGR Position

%

0 %

Desired EGR Position

%

0 %

EGR Sensor

Volts

0.82 Volts

Cam Retard

Degrees

0°±20°

Spark Advance

Degrees

21°

DTC Counter

Counts

0

Engine Run Time

Min/Sec

Varies