GM Service Manual Online
For 1990-2009 cars only
1-2 Shift Time: This parameter displays the actual time of the last adaptable 1-2 shift. The shift time is based on the gear ratio change after the commanded 1-2 shift.

2-3 Shift Time: This parameter displays the actual time of the last adaptable 2-3 shift. The shift time is based on the gear ratio change after the commanded 2-3 shift.

3-4 Shift Time: This parameter displays the actual time of the last adaptable 3-4 shift. The shift time is based on the gear ratio change after the commanded 3-4 shift.

4-5 Shift Time: This parameter displays the actual time of the last adaptable 4-5 shift. The actual shift time is obtained by measuring the time required for the input shaft to decelerate from the previous ratio to the current ratio.

5-6 Shift Time: This parameter displays the actual time of the last 5-6 shift. The shift time is base on the gear ratio change after the commanded 5-6 shift.

Brake Switch: This parameter displays the status of the brake switch circuit input. Applied indicates a zero voltage input, brake pedal applied. Released indicates a voltage input, brake pedal released. The scan tool displays Applied or Released.

Calc. Throttle Position: This parameter displays a calculated value, which is determined by the accelerator pedal position and the actual throttle position, used to optimize transmission controls. The parameter represents the driver's intended request for torque or acceleration. The range is 0-100%, where 0% represents an idle or coast request and 100% represents a request for wide open throttle (WOT).

Commanded Gear: This parameter displays the current commanded state of the shift solenoid valves. The scan tool displays 1, 2, 3, 4 or 5.

Driver Shift Control: This parameter displays Active or Inactive. The scan tool displays Active when the gear selector is in the sport (S) position, which enables TAP shift. The scan tool displays Inactive when the gear selector is not in the S position, TAP shift disabled.

Driver Shift Request: This parameter displays the current request from the TAP Shift System. This parameter will display upshift, downshift or invalid, depending on the amount of voltage measured at the remote shift selector input, and will also display none when there is no request.

ECT: This parameter displays the input signal from the engine coolant temperature (ECT) sensor. ECT is high at 151°C (304°F) when the signal voltage is low, 0 volt. ECT is low at -40°C (-40°F) when the signal voltage is high, 5 volt.

Engine Speed: This parameter displays the rotational speed of the engine expressed as revolutions per minute.

Engine Torque: This parameter displays a calculated value based on engine load, throttle position, mass air flow, and other engine inputs. This parameter is accurate to within 20 N·m (15 ft lb) of actual measured engine torque.

Gear Ratio: This parameter displays the actual transmission gear ratio. The scan tool displays the gear ratio calculated from the automatic transmission input shaft speed sensor (AT ISS) and the automatic transmission output shaft speed sensor (AT OSS) inputs.

High Side Driver 2: This parameter displays the High Side Driver 2 status on the scan tool. When the High Side Driver 2 is commanded OFF this displays Disabled, when the High Side Driver 2 is commanded ON this displays Enabled.

High Side Driver 2 CKT Status: This parameter displays the High Side Driver 2 circuit status on the scan tool. If the voltage is low when the solenoid is commanded OFF, the scan tool will display Open/Short to GND. If the voltage is high when the solenoid is commanded ON, the scan tool will display Short to Volts. If no circuit fault is present the scan tool will display OK, or Indeterminate.

Ignition Voltage: This parameter displays the system voltage measured at the ignition feed.

IMS: This parameter displays PARK, PARK/REVERSE, REVERSE, REVERSE/NEUTRAL, NEUTRAL, NEUTRAL/DRIVE 4, DRIVE 4, DRIVE 4/DRIVE 3, DRIVE 3, DRIVE 3/DRIVE 2, DRIVE 2, DRIVE 2/DRIVE 1, DRIVE 1 or INVALID. The IMS Range display represents a decoded status of the four inputs from the IMS. The combination of IMS inputs are used to determine which position the manual valve is in at any time.

IMS A/B/C/P: This parameter displays the status of the four A/B/C/P inputs from the automatic transmission internal mode switch. I indicates an ignition voltage signal. LOW indicates a 0 voltage signal. The scan tool will display HI/LOW, HI/LOW, HI/LOW, HI/LOW.

ISS/OSS Supply Voltage: This parameter displays OK, Out of Range.

Last Shift Time: This parameter displays the actual time of the last upshift. This value is only accurate if the shift was adaptable.

Line PC Sol. CKT Status: This parameter displays whether an open, short to voltage or ground exists in the line pressure control (PC) solenoid valve feedback signal circuit. The scan tool displays OK, Open/Short to Volts, Short to GND, or Indeterminate.

PC Sol. 2 CKT Status: This parameter displays OK, Open/Short to GND, Short to Volts, or Indeterminate.

PC Sol. 2 Pressure Comm.: This parameter displays Yes or No. Yes, solenoid pressure is commanded. No, solenoid pressure is not commanded.

PC Sol. 3 CKT Status: This parameter displays OK, Open/Short to GND, Short to Volts, or Indeterminate.

PC Sol. 3 Pressure Comm.: This parameter displays Yes or No. Yes, solenoid pressure is commanded. No, solenoid pressure is not commanded.

PC Sol. 4 CKT Status: This parameter displays OK, Open/Short to GND, Short to Volts, or Indeterminate.

PC Sol. 4 Pressure Comm.: This parameter displays Yes or No. Yes, solenoid pressure is commanded. No, solenoid pressure is not commanded.

PC Sol. 5 CKT Status: This parameter displays OK, Open/Short to GND, Short to Volts, or Indeterminate.

PC Sol. 5 Pressure Comm.: This parameter displays Yes or No. Yes, solenoid pressure is commanded. No, solenoid pressure is not commanded.

Shift Sol. 1 CKT Status: This parameter displays OK, Open/Short to GND, Short to Volts, or Indeterminate.

Shift Solenoid 1: This parameter displays the commanded state of the reverse, 1st shift solenoid valve (S1). The scan tool displays On/Off.

Shift Sol. 2 CKT Status: This parameter displays OK, Open/Short to GND, Short to Volts, or Indeterminate.

Shift Solenoid 2: This parameter displays the commanded state of the 2-3, 3-4 shift solenoid valve (S2). The scan tool displays On/Off.

TCC PC Sol. CKT Status: This parameter displays whether an open or short to voltage or ground exists in the torque converter clutch (TCC) pressure control (PC) solenoid valve feedback signal circuit. The scan tool displays OK, Open/Short to Volts, Short to GND, or Indeterminate.

TCC PC Sol. Duty Cycle: This parameter displays the commanded On time of the torque converter clutch (TCC) solenoid valve. The scan tool displays On time in percentage. A reading of 100 percent represents an energized, commanded On state. A reading of 0 percent represents a non-energized commanded OFF state.

TCC PC Sol. Pressure Comm.: This parameter displays Yes or No. Yes, solenoid pressure is commanded. No, solenoid pressure is not commanded.

TCC Slip Speed: This parameter displays the difference between transmission input speed and engine speed. A negative value indicates the engine speed is less than the input speed, deceleration. A positive value indicates the engine speed is greater than the input speed, acceleration. A value of zero indicates the engine speed is equal to the input speed, TCC applied.

TCM Temperature: This parameter displays results in °C (°F).

TFP Switch 1: This parameter displays the state of the first clutch oil pressure switch. The scan tool displays HI/LOW.

TFP Switch 3: This parameter displays the state of the 3rd clutch oil pressure switch. The scan tool displays HI/LOW.

TFP Switch 4: This parameter displays the state of the 4th clutch oil pressure switch. The scan tool displays HI/LOW.

TFP Switch 5: This parameter displays the state of the fifth clutch oil pressure switch. The scan tool displays HI/LOW.

Trans. Fluid Temp.: This parameter displays the input signal of the transmission fluid temperature sensor. Transmission fluid temperature is high, 151°C (304°F), when signal voltage is low, 0 volt. Transmission fluid temperature is low, -40°C (-40°F), when signal voltage is high, 5 volt.

Transmission ISS: This parameter displays the rotational speed of the transmission input shaft. The scan tool displays input shaft speed as revolutions per minute (RPM).

Transmission OSS: This parameter displays the rotational speed of the transmission output shaft. The scan tool displays output shaft speed as revolutions per minute (RPM).