GM Service Manual Online
For 1990-2009 cars

If you have completed the On-Board Diagnostic (OBD) system check, if the diagnostics are functioning properly and if no DTCs display, you may use the values in the table below for comparison within the appropriate transmission. These typical values are an average of display values recorded from normally operating vehicles. They represent the display from a normally functioning system.

Never use a scan tool that displays faulty data. The condition should be reported to the manufacturer. Use of a faulty scan tool can result in misdiagnosis and the unnecessary replacement of parts.

Only the parameters listed below are used in this manual for diagnosing. If a scan tool displays other parameters, the values are not recommended by General Motors for use in diagnosis.

Scan tool values below were recorded under the following conditions:

    • Idle
    • Upper radiator hose is hot
    • Closed throttle
    • Park or Neutral
    • Closed Loop
    • Accessories OFF
    • Brake not applied

Scan Tool Data Value Examples

Scan Tool Parameter

Units Displayed

Typical Scan Values

Engine Torque

N·m (lb ft)

15 N·m (11 lb ft)

TP Sensor

volts

0.51 V

TP Angle

percent

0%

Engine Speed

RPM

900 RPM from PCM commanded idle speed

Transmission OSS

RPM

0

Vehicle Speed

km/h (mph)

0

Current Gear

1, 2, 3, 4

1

1-2 Sol.

On/Off

On

2-3 Sol.

On/Off

On

Gear ratio

Ratio

3.98

1-2 Sol. Open/Short to (Gnd)

Yes/No

No

1-2 Sol. Short to Volts

Yes/No

No

2-3 Sol. Open/Short to (Gnd)

Yes/No

No

2-3 Sol. Short to Volts

Yes/No

No

ECT

°C (°F)

97°C (206°F) (varies with the outside temperature)

IAT

°C (°F)

54°C (129°F)

Trans. Fluid Temp.

°C (°F)

72°C (161°F) (varies with the outside temperature)

TFT Sensor

volts

2.63 V (varies with the Trans. Fluid temperature)

Hot Mode

On/Off

Off

Brake Switch

Open/Closed

Closed

TCC Duty Cycle

percent

0%

TCC Release Pressure

Yes/No

Yes

TCC Slip Speed

RPM

varies

TCC Duty Cycle Open/Short to (Gnd)

Yes/No

No

TCC Duty Cycle Short to Volts

Yes/No

No

Engine Run Time

hours/minutes/seconds

depends on time since start-up

Ignition Voltage

volts

13.1 V

Cruise

Enabled/Disabled

Disabled

A/C Clutch

On/Off

Off

Traction Control

Inactive/Active

Inactive

1-2 Shift Error

seconds

varies

1-2 Shift Time

seconds

varies

1-2 Tap High

psi

varies

1-2 Tap Low

psi

varies

2-3 Shift Error

seconds

varies

2-3 Shift Time

seconds

varies

2-3 Tap High

psi

varies

2-3 Tap Low

psi

varies

3-4 Shift Error

seconds

varies

3-4 Shift Time

seconds

varies

3-4 Tap High

psi

varies

3-4 Tap Low

psi

varies

Adaptable Shift

Yes/No

No

Last Shift

seconds

varies

PC Sol. Actual Current

amps

1.01 amps

PC Solenoid Duty Cycle

percent

58-68%

PC Sol. Ref. Current

amps

1.01 amps

Shift Mode

Normal/Performance

Normal

TFP Automatic Transmission Fluid Pressure Manual Valve Position Sw. A/B/C

On/Off

On/Off/Off

Transmission ISS

RPM

565-665 RPM