This list explains each data message displayed on the scan tool.

This information will assist you in diagnosing emissions or driveability DTCs. Refer to Diagnostic System Check - Automatic Transmission for additional information.

1-2 Shift Error: This parameter displays the difference between the desired 1-2 shift time and the actual 1-2 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.

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 through 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.

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 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 Error: This parameter displays the difference between the desired 2-3 shift time and the actual 2-3 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.

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.

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 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.

3-4 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 or subtracted from shift pressure during a 3-4 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.

A/C Clutch: This parameter displays the commanded state of the air conditioning (A/C) compressor clutch relay driver circuit and displays ON or OFF. The A/C compressor clutch should be engaged when ON displays. When the display indicates ON, the line pressure and the shift times will be adjusted for the additional engine load.

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

Cruise: This parameter displays the commanded state of the cruise control system. The scan tool display ENABLED or DISABLED. When the display indicates ENABLED, the PCM is allowing cruise control operation. When the display indicates DISABLED, the PCM has disabled cruise control operation. When the cruise control display is ENABLED, shift patterns will be altered for 2-3 and 3-4 upshifts or 4-3 and 3-2 downshifts.

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 ECT sensor. Engine coolant temperature is high at 151°C (304°F) when the signal voltage is low (0 V). Engine coolant temperature is low at -40°C (-40°F) when the signal voltage is high (5 V).

Engine Run Time: This parameter displays a measure in Hours/Minutes/Seconds of how long the engine has been operating. When the ignition is cycled to OFF, the value is reset to zero.

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 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.

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 what 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 and LOW indicates a 0 voltage signal. The scan tool will display HI/LOW, HI/LOW, HI/LOW, HI/LOW.

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 results in high line pressure.

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.

PC Solenoid 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.

Steady State TAP 1GR: This parameter displays a pressure modification which is added to the line pressure in 1st gear. The larger the value, the greater the increase to line pressure.

Steady State TAP 2GR: This parameter displays a pressure modification which is added to the line pressure in 2nd gear. The larger the value, the greater the increase to line pressure.

Steady State TAP 2GR/TCC: This parameter displays a pressure modification which is added to the line pressure in 2nd gear with TCC applied. The larger the value, the greater the increase to line pressure.

Steady State TAP 3GR: This parameter displays a pressure modification which is added to the line pressure in 3rd gear. The larger the value, the greater the increase to line pressure.

Steady State TAP 3GR/TCC: This parameter displays a pressure modification which is added to the line pressure in 3rd gear with TCC applied. The larger the value, the greater the increase to line pressure.

Steady State TAP 4GR: This parameter displays a pressure modification which is added to the line pressure in 4th gear. The larger the value, the greater the increase to line pressure.

Steady State TAP 4GR/TCC: This parameter displays a pressure modification which is added to the line pressure in 4th gear with TCC applied. The larger the value, the greater the increase to line pressure.

Steady State TAP Reverse: This parameter displays a pressure modification which is added to the line pressure in REVERSE gear. The larger the value, the greater the increase to line pressure.

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 of 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.

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

TFP Sw. Sig. A/Sig. C: This parameter displays HI/LOW. The displays are the two inputs from the automatic transmission fluid pressure manual valve position switch. LOW represents a low voltage signal, switch closed. HI represents an ignition voltage signal, switch open. The sequence of open and closed switches is used to determine actual manual valve position.

TP Angle: This parameter displays a percentage that is calculated based on TP sensor voltage. The TP angle should display 0 percent at idle and 100 percent at wide open throttle (WOT).

TP Sensor: This parameter displays the TP sensor voltage that is used to determine the amount of throttle demanded by the driver. TP voltage is used to modify line pressure and shift times.

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 the signal voltage is low, 0 V, and transmission fluid temperature is low -40°C (-40°F) when the signal voltage is high, 5 V.

Trans. Oil Life: This parameter displays the transmission oil life remaining. The scan tool displays remaining oil life in percentage. The transmission oil life is calculated based on transmission fluid temperature and engine run time.

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 more than 5 seconds. NOTE: These numbers are approximate. They 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 expressed as revolutions per minute.

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.