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.
1-2 Sol.: This parameter displays the commanded state of the 1-2 shift solenoid valve. When the transmission is in FIRST and FOURTH gear, the display should indicate ON, current is flowing trough the solenoid. When the transmission is in SECOND and THIRD gear, the display should indicate OFF, current is not flowing through the solenoid.
1-2 Sol. CKT Status: This parameter displays the solenoid valve feedback voltage signal 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. Until the circuit has been evaluated, the scan tool will display Indeterminate.
1-2 TAP Cell (4-16): This parameter displays the amount of transmission adaptive pressure (TAP), based on 17 N·m (12.5 lb ft) of engine torque increment per cell, added to or subtracted from shift pressure during a 1-2 upshift. A positive number indicates that long shifts have been detected and PC solenoid pressure has been added in order to decrease shift time. A negative number indicates that short shifts have been detected and PC solenoid pressure has been subtracted in order to increase shift time.
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.
2-3 Sol.: This parameter displays the commanded state of the 2-3 shift solenoid valve. When the transmission is in FIRST and SECOND gear, the display should indicate OFF, current is not flowing through the solenoid. When the transmission is in THIRD and FOURTH gear, the display should indicate ON, current is flowing through the solenoid.
2-3 Sol. CKT Status: This parameter displays the solenoid valve feedback voltage signal 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. Until the circuit has been evaluated, the scan tool will display Indeterminate.
2-3 TAP Cell (4-16): This parameter displays the amount of transmission adaptive pressure (TAP), based on 17 N·m (12.5 lb ft) of engine torque increment per cell, added to or subtracted from shift pressure during a 2-3 upshift. A positive number indicates that long shifts have been detected and PC solenoid pressure has been added in order to decrease shift time. A negative number indicates that short shifts have been detected and PC solenoid pressure has been subtracted in order to increase shift time.
3-4 Shift Error: This parameter displays the difference between the desired 3-4 shift time and the actual 3-4 shift time. A positive number indicates a firm or fast shift, the actual shift time was shorter than the desired shift time. A negative number indicates a soft or slow shift, the actual shift time was longer than the desired shift time. This value is only accurate if the shift was adaptable.
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.
4WD: This parameter displays whether the vehicle is currently in a four-wheel drive mode. The scan tool displays Enabled or Disabled.
4WD Low: This parameter displays the signal state of the four-wheel drive low circuit. Enabled indicates a 0 voltage signal requesting 4WD low. Disabled indicates a B+ voltage signal which does not request 4WD low. The scan tool displays Enabled or Disabled.
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.
Current TAP Cell: This parameter displays the current transmission adaptive pressure (TAP) cell in use for transmission line pressure adaptation. The cells are based on 17 N·m (12.5 lb ft) of engine torque. The higher the engine torque, the higher the current TAP cell. The last cell used will remain displayed until the next adaptable upshift occurs.
ECT: This parameter displays the input signal from the engine coolant temperature (ECT) sensor. The scan tool displays -40 to +151°C (-40 to +304°F). When the ECT is high at 151°C (304°F), the signal voltage is low, 0 V. When the ECT is low at -40°C (-40°F), the signal voltage is high, 5 V. The ECM sends the ECT information to the transmission control module (TCM) via the high speed GMLAN serial data line.
Engine Speed: This parameter displays the engine speed, based on a signal from the engine control module (ECM). The scan tool displays engine speed in revolutions per minute (RPM). The ECM sends the RPM information to the transmission control module (TCM) via the high speed GMLAN serial data line.
Engine Torque: This parameter displays the estimated amount of torque that is delivered from the engine. The scan tool displays engine torque in N·m (lb ft). The ECM sends the engine torque information to the transmission control module (TCM) via the high speed GMLAN serial data line.
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.
Ignition Voltage: This parameter displays the system voltage measured at the ignition feed.
Last Shift Time: This parameter displays the actual time of the last upshift. This value is only accurate if the shift was adaptable.
PC Sol. Actual Current: This parameter displays the actual current flow through the pressure control solenoid circuit, which is measured by the control module. High current flow results in low line pressure. Low current flow results in high line pressure.
PC Sol. Duty Cycle: This parameter displays the commanded state of the pressure control solenoid, expressed as a percentage of energized ON time. A reading of low percent indicates zero ON time, non energized, or no current flow. A high percent at idle indicates maximum ON time, energized, or high current flow.
PC Sol. Ref. Current: This parameter displays the commanded current of the pressure control solenoid circuit. High current results in low line pressure. Low current results in high line pressure.
Power Take-Off: This parameter displays when the Power Take-Off (PTO) is engaged. PTO mode disables all transmission diagnostics. The scan tool displays YES or NO.
Speed Ratio: This parameter displays the calculated speed ratio of the transmission. The ratio is calculated by dividing the output speed sensor signal by the input speed sensor signal. Gear ratio in a step-gear transmission is calculated in the opposite manner.
TCC Brake Switch: This parameter displays the status of the TCC brake switch circuit input. OPEN indicates a zero voltage input, brake pedal applied. CLOSED indicates a voltage input, brake pedal released. The scan tool displays OPEN or CLOSED.
TCC Duty Cycle: This parameter displays the commanded percentage of ON time for the TCC PWM solenoid. A high percentage represents an ON, energized, commanded state. 0 percent represents an OFF, non-energized, commanded state.
TCC Duty Cycle CKT Status: This parameter displays the solenoid driver feedback voltage signal and displays the 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. Until the circuit has been evaluated, the scan tool will display Indeterminate.
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.
TFP Sw.: This parameter displays Park/Neutral, Reverse, Drive4, Drive3, Drive2, Drive1 or invalid. This parameter is the decoded status of the three A/B/C inputs from the automatic transmission fluid pressure manual valve position switch. If a valid combination of inputs is not detected, invalid will be displayed.
TFP Sw. A/B/C: This parameter displays HI/LOW, HI/LOW, HI/LOW. This parameter indicates the status of the three inputs from the automatic transmission fluid pressure manual valve position switch assembly. LOW represents a zero voltage signal. HI represents an ignition voltage signal.
TR Sw.: This parameter displays the decoded status of the four A/B/C/P inputs from the transmission range switch. The scan tool displays Park, Reverse, Neutral, Drive, Intermediate, Low, and invalid. If a valid combination of inputs is not detected, invalid will be displayed.
TR Sw. A/B/C/P: This parameter displays the status of the four inputs from the transmission range switch. The scan tool displays HI/LOW. HI indicates an ignition voltage input to the control module. LOW indicates a zero voltage input to the control module.
Transfer Case Ratio: This parameter displays the ratio of the transfer case, calculated by engine speed, divided by transmission output speed based on transmission commanded gear.
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.
Trans. Slip Counter: This parameter displays the number of times the P0894 diagnostic test has identified a slipping condition. This diagnostic test is required, to identify a slipping condition three times in a row in order to set the DTC P0894 Transmission Component Slipping diagnostic code. The scan tool displays 0, 1 or 2.
Transmission Hot Mode: This parameter displays the automatic transmission fluid temperature (TFT) and displays On or Off. Off indicates that the TFT has not exceeded 130°C (266°F). On indicates that the TFT has exceeded 130°C (266°F) and has not cooled to 120°C (248°F) for greater that 5 seconds. These numbers are approximate and differ with transmissions.
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). On four-wheel drive applications, the transfer case output shaft speed is measured.
Turbine Speed: This parameter displays the rotational speed of the torque converter turbine shaft, and is expressed as revolutions per minute (RPM). In commanded gears 1, 2, and 3, the turbine speed equals the input speed. In commanded gear 4, the turbine speed equals 3/4 of the input speed.
Vehicle Speed: This parameter displays the speed at which the vehicle is traveling. The scan tool displays vehicle speed as kilometers per hour (km/h), miles per hour (MPH). The vehicle speed is calculated based on the input signal from the automatic transmission output shaft speed sensor.
1-2 Sol.: This parameter displays the commanded state of the 1-2 shift solenoid valve. When the transmission is in FIRST and FOURTH gear, the display should indicate ON, current is flowing trough the solenoid. When the transmission is in SECOND and THIRD gear, the display should indicate OFF, current is not flowing through the solenoid.
1-2 Sol. CKT Status: This parameter displays the solenoid valve feedback voltage signal 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. Until the circuit has been evaluated, the scan tool will display Indeterminate.
1-2 TAP Cell (4-16): This parameter displays the amount of transmission adaptive pressure (TAP), based on 17 N·m (12.5 lb ft) of engine torque increment per cell, added to or subtracted from shift pressure during a 1-2 upshift. A positive number indicates that long shifts have been detected and PC solenoid pressure has been added in order to decrease shift time. A negative number indicates that short shifts have been detected and PC solenoid pressure has been subtracted in order to increase shift time.
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.
2-3 Sol.: This parameter displays the commanded state of the 2-3 shift solenoid valve. When the transmission is in FIRST and SECOND gear, the display should indicate OFF, current is not flowing through the solenoid. When the transmission is in THIRD and FOURTH gear, the display should indicate ON, current is flowing through the solenoid.
2-3 Sol. CKT Status: This parameter displays the solenoid valve feedback voltage signal 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. Until the circuit has been evaluated, the scan tool will display Indeterminate.
2-3 TAP Cell (4-16): This parameter displays the amount of transmission adaptive pressure (TAP), based on 17 N·m (12.5 lb ft) of engine torque increment per cell, added to or subtracted from shift pressure during a 2-3 upshift. A positive number indicates that long shifts have been detected and PC solenoid pressure has been added in order to decrease shift time. A negative number indicates that short shifts have been detected and PC solenoid pressure has been subtracted in order to increase shift time.
3-4 Shift Error: This parameter displays the difference between the desired 3-4 shift time and the actual 3-4 shift time. A positive number indicates a firm or fast shift, the actual shift time was shorter than the desired shift time. A negative number indicates a soft or slow shift, the actual shift time was longer than the desired shift time. This value is only accurate if the shift was adaptable.
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.
4WD: This parameter displays whether the vehicle is currently in a four-wheel drive mode. The scan tool displays Enabled or Disabled.
4WD Low: This parameter displays the signal state of the four-wheel drive low circuit. Enabled indicates a 0 voltage signal requesting 4WD low. Disabled indicates a B+ voltage signal which does not request 4WD low. The scan tool displays Enabled or Disabled.
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.
Current TAP Cell: This parameter displays the current transmission adaptive pressure (TAP) cell in use for transmission line pressure adaptation. The cells are based on 17 N·m (12.5 lb ft) of engine torque. The higher the engine torque, the higher the current TAP cell. The last cell used will remain displayed until the next adaptable upshift occurs.
ECT: This parameter displays the input signal from the engine coolant temperature (ECT) sensor. The scan tool displays -40 to +151°C (-40 to +304°F). When the ECT is high at 151°C (304°F), the signal voltage is low, 0 V. When the ECT is low at -40°C (-40°F), the signal voltage is high, 5 V. The ECM sends the ECT information to the transmission control module (TCM) via the high speed GMLAN serial data line.
Engine Speed: This parameter displays the engine speed, based on a signal from the engine control module (ECM). The scan tool displays engine speed in revolutions per minute (RPM). The ECM sends the RPM information to the transmission control module (TCM) via the high speed GMLAN serial data line.
Engine Torque: This parameter displays the estimated amount of torque that is delivered from the engine. The scan tool displays engine torque in N·m (lb ft). The ECM sends the engine torque information to the transmission control module (TCM) via the high speed GMLAN serial data line.
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.
Ignition Voltage: This parameter displays the system voltage measured at the ignition feed.
Last Shift Time: This parameter displays the actual time of the last upshift. This value is only accurate if the shift was adaptable.
PC Sol. Actual Current: This parameter displays the actual current flow through the pressure control solenoid circuit, which is measured by the control module. High current flow results in low line pressure. Low current flow results in high line pressure.
PC Sol. Duty Cycle: This parameter displays the commanded state of the pressure control solenoid, expressed as a percentage of energized ON time. A reading of low percent indicates zero ON time, non energized, or no current flow. A high percent at idle indicates maximum ON time, energized, or high current flow.
PC Sol. Ref. Current: This parameter displays the commanded current of the pressure control solenoid circuit. High current results in low line pressure. Low current results in high line pressure.
Power Take-Off: This parameter displays when the Power Take-Off (PTO) is engaged. PTO mode disables all transmission diagnostics. The scan tool displays YES or NO.
Speed Ratio: This parameter displays the calculated speed ratio of the transmission. The ratio is calculated by dividing the output speed sensor signal by the input speed sensor signal. Gear ratio in a step-gear transmission is calculated in the opposite manner.
TCC Brake Switch: This parameter displays the status of the TCC brake switch circuit input. OPEN indicates a zero voltage input, brake pedal applied. CLOSED indicates a voltage input, brake pedal released. The scan tool displays OPEN or CLOSED.
TCC Duty Cycle: This parameter displays the commanded percentage of ON time for the TCC PWM solenoid. A high percentage represents an ON, energized, commanded state. 0 percent represents an OFF, non-energized, commanded state.
TCC Duty Cycle CKT Status: This parameter displays the solenoid driver feedback voltage signal and displays the 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. Until the circuit has been evaluated, the scan tool will display Indeterminate.
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.
TFP Sw.: This parameter displays Park/Neutral, Reverse, Drive4, Drive3, Drive2, Drive1 or invalid. This parameter is the decoded status of the three A/B/C inputs from the automatic transmission fluid pressure manual valve position switch. If a valid combination of inputs is not detected, invalid will be displayed.
TFP Sw. A/B/C: This parameter displays HI/LOW, HI/LOW, HI/LOW. This parameter indicates the status of the three inputs from the automatic transmission fluid pressure manual valve position switch assembly. LOW represents a zero voltage signal. HI represents an ignition voltage signal.
TR Sw.: This parameter displays the decoded status of the four A/B/C/P inputs from the transmission range switch. The scan tool displays Park, Reverse, Neutral, Drive, Intermediate, Low, and invalid. If a valid combination of inputs is not detected, invalid will be displayed.
TR Sw. A/B/C/P: This parameter displays the status of the four inputs from the transmission range switch. The scan tool displays HI/LOW. HI indicates an ignition voltage input to the control module. LOW indicates a zero voltage input to the control module.
Transfer Case Ratio: This parameter displays the ratio of the transfer case, calculated by engine speed, divided by transmission output speed based on transmission commanded gear.
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.
Trans. Slip Counter: This parameter displays the number of times the P0894 diagnostic test has identified a slipping condition. This diagnostic test is required, to identify a slipping condition three times in a row in order to set the DTC P0894 Transmission Component Slipping diagnostic code. The scan tool displays 0, 1 or 2.
Transmission Hot Mode: This parameter displays the automatic transmission fluid temperature (TFT) and displays On or Off. Off indicates that the TFT has not exceeded 130°C (266°F). On indicates that the TFT has exceeded 130°C (266°F) and has not cooled to 120°C (248°F) for greater that 5 seconds. These numbers are approximate and differ with transmissions.
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). On four-wheel drive applications, the transfer case output shaft speed is measured.
Turbine Speed: This parameter displays the rotational speed of the torque converter turbine shaft, and is expressed as revolutions per minute (RPM). In commanded gears 1, 2, and 3, the turbine speed equals the input speed. In commanded gear 4, the turbine speed equals 3/4 of the input speed.
Vehicle Speed: This parameter displays the speed at which the vehicle is traveling. The scan tool displays vehicle speed as kilometers per hour (km/h), miles per hour (MPH). The vehicle speed is calculated based on the input signal from the automatic transmission output shaft speed sensor.
