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