The Engine Scan Tool Data Definitions contains a brief description of all engine related parameters available on the scan tool. The list is in alphabetical order. A given parameter may appear in any one of the data lists. In some cases, the parameter may appear more than once or in more than one data list in order to group certain related parameters together.

1-4 Shift Lamp: The scan tool displays On or Off. When the PCM enables the 1-4 shift solenoid, the 1-4 shift lamp comes on and the scan tool displays ON. The scan tool displays OFF under the normal operating conditions.

1-4 Shift Solenoid: The scan tool displays Enabled or Disabled. When the PCM enables the 1-4 shift solenoid, the scan tool displays Enabled. The scan tool displays Disabled under the normal operating conditions.

A/C Relay Command: The scan tool displays On or Off. The A/C Clutch represents the PCM commanded state of the A/C clutch control relay. When the scan tool indicates ON, the A/C clutch should be engaged.

A/C High Side Pressure: The scan tool displays 103-3116 kPa/15-452 psi. This parameter represents the A/C refrigerant pressure sensor signal. The amount of pressure indicates the amount of load that the A/C compressor places on the engine. The PCM uses this information in order to adjust idle and in order to control the cooling fans.

A/C High Side Pressure: The scan tool displays 0-5 volts. This parameter represents the A/C refrigerant pressure sensor signal. The amount of pressure indicates the amount of load that the A/C compressor places on the engine. The PCM uses this information in order to adjust idle and in order to control the cooling fans.

A/C Request: The scan tool displays Yes or No. The A/C Request indicates the state of the A/C request input circuit from the HVAC controls (C60). Vehicles equipped with the CJ2 A/C system, uses the Class 2 serial data to inform the PCM that the A/C is requested. The PCM uses the A/C request signal in order to determine whether the A/C compressor operation is being requested.

A/C Status: The scan tool displays On or Off. The scan tool displays ON when the voltage is applied to the A/C compressor clutch.

Air Fuel Ratio: The scan tool displays the ratio of the air to fuel. A typical ratio is about 14.7:1.

AIR Pump Relay: The scan tool displays On or Off. When the PCM grounds the AIR pump relay control circuit, the scan tool indicates ON. When the PCM disables the ground circuit, the scan tool indicates OFF.

AIR Solenoid Relay: The scan tool displays On or Off. When the PCM grounds the AIR pump solenoid control circuit, the scan tool indicates ON. When the PCM disables the ground circuit, the scan tool indicates OFF.

APP Average: The scan tool displays 0-125 counts. The TAC Module takes the voltages from the 3 APP Sensors, averages the readings and converts the readings into counts. The scan tool displays the average. The average is different on every vehicle.

APP Indicated Angle: The scan tool displays 0-100 percent. The scan tool displays the Accelerator Pedal Position in percentage. When the APP is at rest, the display shows 0 percent. When the APP is fully depressed, the display shows 100 percent.

APP Sensor 1: The scan tool displays 0-5 volts. When the accelerator pedal is at 0 percent (pedal at rest), the display shows less than 1.1 volt. When the accelerator pedal is at 100 percent (pedal fully depressed), the display shows more than 2.0 volts.

APP Sensor 2: The scan tool displays 5-0 volts. When the accelerator pedal is at 0 percent (pedal at rest), the display shows more than 3.9 volts. When the accelerator pedal is at 100 percent (pedal fully depressed), display shows less than 3.0 volt.

APP Sensor 3: The scan tool displays 5-0 volts. When the accelerator pedal is at 0 percent (pedal at rest), display shows more than 3.2 volts. When the accelerator pedal is at 100 percent (pedal fully depressed), display shows less than 3.5 volts.

APP Sensor 1 Angle: The scan tool displays 0-100 percent. When the accelerator pedal is at rest, display shows 0 percent. When the accelerator pedal is fully depressed, display shows 100 percent. This percentage indicates to the TAC Module the actual pedal position.

APP Sensor 2 Angle: The scan tool displays 0-100 percent. When the accelerator pedal is at rest, display shows 0 percent. When the accelerator pedal is fully depressed, display shows 100 percent. This percentage indicates to the TAC Module the actual pedal position

APP Sensor 3 Angle: The scan tool displays 0-100 percent. When the accelerator pedal is at rest, display shows 0 percent. When the accelerator pedal is fully depressed, display shows 100 percent. This percentage indicates to the TAC Module the actual pedal position.

APP Sensor 1 Out of Range: The scan tool displays Yes or No. If the APP Sensor voltage is not within the specifications, the scan tool displays YES. If the APP Sensor voltage is within the specifications, the scan tool displays No.

APP Sensor 2 Out of Range: The scan tool displays Yes or No. If the APP Sensor voltage is not within the specifications, the scan tool displays YES. If the APP Sensor voltage is within the specifications, the scan tool displays No.

APP Sensor 3 Out of Range: The scan tool displays Yes or No. If the APP Sensor voltage is not within the specifications, the scan tool displays YES. If the APP Sensor voltage is within the specifications, the scan tool displays No.

APP Sen. 1 and APP Sen .2 Disagree: The scan tool displays Yes or No. When the TAC module receives a signal voltage from APP Sensor 1 not in proper relationship to APP Sensor 2, the scan tool displays YES. The scan tool displays NO under the normal operating conditions.

APP Sen. 1 and APP Sen. 3 Disagree: The scan tool displays Yes or No. When the TAC module receives a signal voltage from APP Sensor 1 not in proper relationship to APP Sensor 3, the scan tool displays YES. The scan tool displays NO under the normal operating conditions.

APP Sen. 2 and APP Sen. 3 Disagree: The scan tool displays Yes or No. When the TAC module receives a signal voltage from APP Sensor 2 not in proper relationship to APP Sensor 3, the scan tool displays YES. The scan tool displays NO under the normal operating conditions.

BARO: Scan Tool Range 10-105 kPa/0.0-50 volts. The Barometric Pressure reading is determined from the MAP sensor signal. The PCM monitors the MAP signal during key up and Wide-Open Throttle (WOT) conditions. The Barometric Pressure compensates for altitude differences.

CAM Signal Input High to Low: The scan tool displays 0-65,535 counts. The counts increment as the PCM detects the Camshaft sensor signal voltage going from high to low.

CAM Signal Input Low to High: The scan tool displays 0-65,535 counts. The counts increment as the PCM detects the Camshaft sensor signal voltage going from low to high.

CC Brake Switch: The scan tool displays Applied or Released (manual transmission). This parameter indicates the state of the TCC/CC brake switch circuit input. Open indicates 0 voltage input (brake switch open, brake pedal applied). Closed indicates a B+ voltage input (brake switch closed, brake pedal released). When you apply the vehicle brakes, the scan tool displays Applied. The torque converter clutch and cruise control disengages. When you release the vehicle brakes, the scan tool displays Released. This allows the cruise control to be resumed and the torque converter clutch to engage.

Clutch Switch: The scan tool displays Depressed or Released. When the vehicle clutch pedal is depressed the scan tool display shows Depressed, and the cruise control will disengage. When the vehicle clutch pedal is released, the scan tool displays Released, and the cruise control can be resumed.

Cold Start Up: The scan tool displays Yes or No. A cold start-up is when the engine coolant temperature rises above a predetermined temperature during an ignition cycle. The next ignition cycle the engine coolant temperature should be below a predetermined temperature. Also the engine coolant temperature and the air intake temperature are less than 50°C (122°F) and are within 3°C (5°F) of each other at start-up. When the above is true the scan tool displays Yes.

Column Lock Fuel Disable-ABS DTC: The scan tool displays Yes or No. The PCM disables fuel when an ABS wheel speed sensor and a BCM DTC sets. When this failure occurs the engine will start and then stall after 5 seconds. The engine will not start if you attempt to start the engine on that same ignition cycle.

Column Lock Fuel Disable-BCM DTC: The scan tool displays Yes or No. The PCM disables the fuel when a BCM DTC related to the column lock system is detected. The engine will start and idle. When the vehicle reaches 1.5 mph the PCM disables fuel. This occurs because the status of the column lock position is unknown.

Column Lock PCM-BCM Com.: The scan tool displays Fault or OK. The PCM disables fuel when a Serial data communication malfunction occurs between the PCM and the BCM. The engine will start and idle. When the vehicle reaches 1.5 mph the PCM disables fuel. This occurs because the status of the column lock position is unknown.

Cruise Disengage History 1-8: The Scan tool displays the last 8 cruise control disengages in order from 1 to 8. There are 20 possible causes for the cruise control to disengage. Refer to Cruise Control Diagnosis for descriptions.

Cruise Requested: The scan tool displays Yes or No. When the Cruise control switch is in the on position and the Set/Coast switch is activated the scan tool displays YES. When the cruise control switch is in the ON position and the Set/Coast switch is released the scan tool displays NO.

Cruise Resume/Accel: The scan tool displays On or Off. When the Cruise control switch is in the on position and the Resume/Accel switch is activated, the scan tool displays ON. When the Resume/Accel switch is released the scan tool displays OFF.

Cruise Set/Coast: The scan tool displays On or Off. When the Cruise control switch is in the on position and the Set/Coast switch is activated, the scan tool displays ON. When the Set/Coast switch is released the scan tool displays OFF.

Cruise Switch: The scan tool displays On or Off. When you activate the cruise control switch, the scan tool displays ON. The switch, when in the ON position, sends a signal voltage to the Throttle Actuator Control (TAC) Module. This allows all other functions of the Cruise Control. When you turn off the cruise control switch, the scan tool displays OFF.

Current Gear: The scan tool displays 0-4. The scan tool displays which gear the transmission is in. The scan tool displays 9 if the transmission gear is unknown.

Cycles of Misfire Data: Scan Tool Range 0-100. The PCM Counts the number of misfire tests during 200 revolutions.

Cyl. Mode Misfire Index: Scan Tool Range 0-65,535. This parameter displays the amount of crankshaft decelerations. When an engine is operating without a misfire, the scan tool displays less then 1000 counts. When an engine misfire occurs, the counter displays more than 1000 counts.

DTC Set This Ignition: The scan tool displays Yes or No. This parameter indicates if a Diagnostic Trouble Code has set on the current ignition cycle.

Delivered Torque: The scan tool displays -473 to 473 N·m/-349 to 349 ft-lbs. This is the calculated torque output from the engine to the transaxle used by the EBTCM for the traction control system operation.

Desired Idle Speed: Scan Tool Range 0-3187 RPM. The PCM commands the desired idle speed. The PCM compensates for various engine loads in order to keep the engine at the desired speed.

Desired Torque: The scan tool displays -473 to 473 N·m/-349 to 349 ft-lbs. The EBTCM sends a Desired Torque Level signal request to the PCM. This decreases torque from the Powertrain in order to reduce wheel slip during acceleration for the traction control.

ECT: Scan Tool Range -39°C to 140°C (-38°F to 284°F). The Engine Coolant Temperature (ECT) sensor parameter displays the temperature of the engine.

Engine Load: Scan Tool Range 0-100 percent. The PCM calculates the Engine Load from engine speed and MAF sensor readings. The Engine Load increases with an increase in RPM or airflow.

Engine Oil Life Remaining: The scan tool displays 0-100 percent. The scan tool displays the percent of Engine Oil Life Remaining. The PCM calculates the Engine Oil Life by monitoring engine load, engine temperature, and engine speed, etc.

Engine Oil Pressure: The scan tool displays 0-992 kPa/0-144 psi. The scan tool displays engine oil pressure.

Engine Run Time: The scan tool displays Hours, Minutes, Seconds. This indicates the amount of Engine Run Time. When the ignition is cycled off, the timer will reset to zero.

Engine Speed: Scan Tool Range 0-10,000 RPM. The PCM computes Engine speed from the ignition reference pulses. The Engine speed should remain close to desired idle under various engine loads with the engine idling.

EOP Sensor: The scan tool displays 0-5 volts. Scan tool displays engine oil pressure in volts.

EVAP Canister Purge: Scan Tool Range 0-100 percent. The PCM commands the PWM duty cycle of the EVAP Purge Solenoid valve. 0 percent displayed indicates no purge; 100 percent displayed indicates full purge.

EVAP Canister Vent Valve: The scan tool displays Venting or Not Venting. The EVAP Canister Vent Valve is normally open (venting). The PCM commands the EVAP Canister Vent Valve closed (not venting) during testing of the EVAP system.

Extended Travel Brake Switch: The scan tool displays Applied or Released. This parameter indicates the state of the extended travel brake switch. This switch is normally closed with the brake pedal released. Scan tool displays Released with the brake pedal released. Scan tool displays Applied with the brake pedal applied approximately greater than 40 percent.

Fail Counter: The scan tool displays the number of times a diagnostic failed.

FC Relay 1: The scan tool displays On or Off. When the PCM commands a coolant fan relay ON, the scan tool indicates ON. When cooling fan relay #1 is activated, both fans are enabled on low speed.

FC Relay 2 and 3: The scan tool displays On or Off. When the PCM commands a coolant fan relay ON, the scan tool indicates ON. When cooling fan relays #2 and #3 are activated, in conjunction with cooling fan relay #1, the cooling fans are enabled on high speed.

Fuel Level Sensor Left Tank: The scan tool displays 5-0 volts. The PCM supplies a 5 volt signal circuit to the fuel level sensor. The float inside the fuel tank is a variable resistor which varies the resistance based on fuel level. The PCM then averages this voltage and the signal voltage from the right tank in order to determine fuel level. The scan tool displays close to 0.7 volts for an empty tank, and close to 2.5 volts for a full tank.

Fuel Level Sensor Right Tank: The scan tool displays 0-5 volts. The PCM supplies a 5 volt signal circuit to the fuel level sensor. The float inside the fuel tank is a variable resistor which varies resistance based on fuel level. The PCM then averages this voltage as well as the signal voltage from the left tank in order to determine fuel level. The scan tool displays close to 0.7 volts for an empty tank, and close to 2.5 volts for a full tank

Fuel Tank Level Remaining: The scan tool displays 0-73 L (0-19 gal). The scan tool displays in Liters or Gallons the amount of fuel remaining in the fuel tank.

Fuel Tank Level Remaining: The scan tool displays 0-100 percent. The scan tool displays in percentage the amount of fuel remaining in the fuel tanks.

Fuel Tank Pressure Sensor: The scan tool displays -32.7 to 13.96 mm/Hg or -17.4 to 7.5 in/H2O. This parameter indicates the pressure/vacuum inside the fuel tank. A negative value indicates a vacuum. A positive value indicates a pressure.

Fuel Tank Pressure Sensor: The scan tool displays 0-5 volts. The scan tool displays in voltage the pressure/vacuum inside the fuel tank.

Fuel Tank Rated Capacity: The scan tool displays 73 L (19 gal). The scan tool displays the capacity of the fuel tank in Liters or Gallons.

Fuel Trim Cell: The scan tool displays a range of 0 to 23. The PCM determines from the MAP sensor and the engine speed which fuel trim cell to operate the engine in . The fuel trim cell displayed on the scan tool is the cell that the engine is operating under.

F.T Diag. Inhibited: This parameter indicates when the PCM is disabling the Fuel Trim Diagnostic.

Fuel Trim Learn: The scan tool displays Enabled or Disabled. When conditions are appropriate for enabling long term fuel trim corrections, the scan tool displays Enabled. This indicates that the long term fuel trim is responding to the short term fuel trim. If the scan tool displays Disabled, then long term fuel trim will not respond to changes in short term fuel trim.

Generator F Terminal: The scan tool displays 0-100 percent. The display shows Generator F Terminal duty cycle in percent from 0-100 percent. The generator is able to produce the desired voltage by varying the duty cycle of the field current.

Generator L Terminal: The scan tool displays Active or Inactive. The scan tool displays Inactive if the PCM does not detect a correct voltage on the L terminal circuit. The scan tool displays Active under the normal operating conditions.

HO2S Bank 1 and Bank 2 Sensor 1: Scan Tool Range 0-1,000 mV. The HO2S Bank 1 and 2 Sensor 1 parameter represents the fuel control exhaust oxygen sensor output voltage. The voltage should fluctuate constantly within a range between 10 mV (lean exhaust) and 1,000 mV (rich exhaust) while operating in Closed Loop.

HO2S Bank 1 and Bank 2 Sensor 2: Scan Tool Range 0-1,000 mV. The HO2S Bank 1 and 2 Sensor 2 parameter represents the rear exhaust oxygen sensor output voltage. The voltage should fluctuate constantly within a range between 10 mV (lean exhaust) and 1,000 mV (rich exhaust) while operating in Closed Loop.

IAT: Scan Tool Range -39°C to 140°C (-38°F to 284°F). The PCM converts the resistance of the intake air temperature sensor to degrees. The PCM uses the Intake Air Temperature (IAT) in order to adjust fuel delivery and spark timing according to incoming air temperature.

IC Circuit Cylinder 1-8: The scan tool displays OK or Fault. If there is a concern with an ignition control circuit, the scan tool displays Fault. The scan tool displays OK under the normal operating conditions.

Ignition 1: The scan tool displays 0-25.5 volts. The Ignition 1 represents the system voltage measured by the PCM at its ignition feed.

Inj. PWM Average Bank 1 and Bank 2: Scan Tool Range 0-1,000 m/sec. The Injector average Indicates the amount of time the PCM commands each injector ON during each engine cycle. A longer injector pulse width causes more fuel to be delivered. The Injector Pulse Width should increase with an increased engine load.

Knock Retard: Scan Tool Range 0°-16°. The Knock Retard indicates the amount of spark advance the PCM removes from the IC spark advance in response to the signal from the Knock sensors.

Long FT1 and 2 Average: The scan tool displays Percentage. This parameter indicates the average of all long term fuel trim cells. The short term fuel trim cells are rated (Weighted) for the amount of which they are used. For example, an idle cell is rated higher then a wide open cell. If a fueling malfunction occurs in the idle cell and the wide open cell, the average would be more affected by the idle cell then the wide open cell. A negative value significantly below 0 percent indicates that the fuel system is rich and fuel delivery is being reduced (decreased injector pulse width). A positive value significantly greater than 0 percent indicates that a lean condition exists and the PCM compensates by adding fuel (increased injector pulse width). When the average of the cells reach a predetermined high or low, a fuel trim DTC will set.

Long Term FT Bank 1 and 2: The scan tool displays Percentage. The PCM derives the Long Term Fuel Trim from the Short Term Fuel Trim value. The Long Term Fuel Trim represents a long-term correction of fuel delivery. A value of 0 percent indicates that fuel delivery requires no compensation in order to maintain the PCM commanded air/fuel ratio. A negative value significantly below 0  percent indicates that the fuel system is rich and the PCM is reducing the fuel delivery (decreased injector pulse width). A positive value significantly greater than 0 percent indicates that a lean condition exists and the PCM compensates by adding fuel (increased injector pulse width). Fuel trim values at maximum authority may indicate an excessively rich or lean system.

Loop Status: The scan tool displays Open or Closed. Closed Loop indicates that the PCM is controlling fuel delivery according to oxygen sensor voltage. In Open Loop, the PCM ignores the oxygen sensor voltage and bases the amount of fuel to be delivered on TP sensor, engine coolant, and MAF sensor inputs only.

Low Oil Level: The scan tool displays Yes or No. This parameter indicates when the engine oil level is low. The scan tool displays YES when the PCM detects the engine oil level is low.

MAF: Scan Tool Range 0.0-655 g/s. MAF (Mass Air Flow) is the MAF Input Frequency converted to grams of air per second. This indicates the amount of air entering the engine.

MAF Frequency: The scan tool displays 0-31,999 Hz. The MAF converts current draw required (to keep the hot wires at a constant temperature) into a frequency signal. The scan tool displays this frequency in Hertz.

MAP: Scan Tool Range 10-105 kPa/0.0-5 volts. The Manifold Absolute Pressure (MAP) sensor measures the change in the intake manifold pressure from engine load, and speed changes. As intake manifold pressure increases, the intake vacuum decreases resulting in a higher MAP sensor voltage and kPa reading. The PCM uses the MAP sensor signal for the following: (1) Updating the BARO reading; (2) Enabling factor for several of the diagnostics.

MIL: The scan tool displays On or Off. The scan tool indicates if the PCM has commanded the Malfunction Indicator Light (MIL) ON.

Mileage Since DTC Cleared: The scan tool displays Km or Miles. This parameter indicates the mileage accumulated since an emission Diagnostic Trouble Code cleared. The PCM stores this mileage in the Freeze Frame and Failure Records memory.

Mileage Since First Fail: The scan tool displays Km or Miles. This parameter indicates the mileage accumulated since an emission Diagnostic Trouble Code first failed. The PCM stores this mileage in the Freeze Frame and Failure Records memory.

Mileage Since Last Fail: The scan tool displays Km or Miles. This parameter indicates the mileage accumulated since an emission Diagnostic Trouble Code last failed. The PCM stores this mileage in the Failure Records memory.

Mileage Since MIL Request: The scan tool displays Km or Miles. This parameter displays the mileage accumulated since the PCM requested the MIL to illuminate. The PCM stores the mileage in the Failure Records memory.

Misfire Current Cylinder 1- 8: Scan Tool Range 0-255 Counts. The Misfire Current counters increment at a rate according to the number of possible misfires the PCM detects on each cylinder during the last 200 firing events. The counters may normally display some activity, but the activity should be nearly equal for all the cylinders.

Misfiring Cylinder: The scan tool displays Prim. Cyl # 0-8 and Sec. Cyl # 0-8. When a multiple misfire occurs, the scan tool displays the cylinder with the most significant misfire under Prim. Cyl. The scan tool displays the least significant misfire under Sec. Cyl.

Misfire Failures: Scan tool displays 0-65,535 Counts. The Misfire Failure counter shows the relative number of failed misfire tests since the misfire DTC P0300 became active.

Misfire History Cylinder 1- 8: Scan Tool Range 0-65,535 Counts. The Misfire History counters display the total level of misfire that has been detected on each cylinder. The Misfire History counters will not update or show any activity until a misfire DTC P0300 has become active. The Misfire History counters will update every 200 firing events.

Misfire Revolution Status: The scan tool displays Reject/Accept. This parameter indicates that the misfire diagnostic is inhibited. The scan tool displays Reject when the conditions for running the DTC are not in range

Not Run Counter: The scan tool displays 0-65,535 counts. The scan tool displays the number of times a DTC has not reached the predetermined criteria in order to run since the first failure.

Pass Counter: The scan tool displays 0-65,535 counts. The scan tool displays the number of times a DTC has passed, since the first failure.

PCM/VCM in VTD Fail Enabled: The scan tool displays YES or NO. If the BCM and PCM lose communications with each other after sending the correct password, the PCM will enable a VTD Fail-Enable mode. This allows the driver to restart the vehicle on future ignition cycles until the communications between the BCM and PCM are restored. The scan tool displays NO under normal operating conditions.

PCM Reset: The scan tool displays Yes or No. This parameter indicates when the PCM resets. The scan tool displays YES when an internal PCM reset occurred. The scan tool displays NO under the normal operating conditions.

PRND A, B, C, P: The scan tool displays a combination of switch patterns. Refer to DTC P0705 Trans Range Switch Circuit or DTC P0706 Trans Range Switch Performance for further information.

PRND Position: The scan tool displays which position the gear shift lever is in. Refer to DTC P0705 Trans Range Switch Circuit or DTC P0706 Trans Range Switch Performance for further information.

Powertrain Induced Chassis Pitch: The scan tool displays Active or Inactive. The scan tool displays Active when the PCM determines from various inputs (MAF, TP, APP, MAP, etc.) that occurring conditions would cause the vehicle's chassis to pitch. The scan tool displays Inactive under the normal operating conditions.

Reduced Engine Power: The scan tool displays Active or Inactive. The scan tool displays Active when the PCM receives a signal from the TAC module that a throttle actuator control system fault is occurring. The PCM limits the engine power.

Reverse Inhibit: The scan tool displays Yes or No (Manual Transmission). When vehicle speed is above 4 mph, the PCM enables the reverse inhibit solenoid, and the scan tool indicates Yes.

Revolutions w/Misfire: The scan tool displays Counts. The counts displayed are the number of engine revolutions with misfire counts detected in the last misfire test.

SHRT FT1 and 2 Average: The scan tool displays Percentage. This parameter indicates the average of the short term fuel trim cells. The short term fuel trim cells are rated (Weighted) for the amount of which they are used. For example, the PCM rates an idle cell higher then a wide open cell. If a fueling malfunction occurs in the idle cell and the wide open cell, the idle cell would affect more than then the wide open cell. A negative value significantly below 0 percent indicates that the fuel system is rich and the PCM is reducing the fuel delivery (decreased injector pulse width). A positive value significantly greater than 0 percent indicates that a lean condition exists and the PCM is compensating by adding fuel (increased injector pulse width). When the average of the cells reach a predetermined high or low, a fuel trim DTC sets.

Short Term FT Bank 1 and 2: The scan tool displays Percentage. The Short Term Fuel Trim represents a short-term correction to fuel delivery by the PCM in response to the amount of time the fuel control oxygen sensor voltage spends above or below the 450 mV threshold. If the oxygen sensor voltage averages less than 450 mV, indicating a lean air/fuel mixture, short term fuel trim increases into the positive range above 0 percent. The PCM adds fuel. If the oxygen sensor voltage averages above the 450 mV threshold, the short term fuel trim decreases below 0 percent into the negative range. The PCM reduces the fuel delivery in order to compensate for the indicated rich condition. Under certain conditions such as an extended idle and a high ambient temperature, the canister purge may cause the Short Term Fuel Trim to read in the negative range during normal operation. The Fuel trim values at maximum authority may indicate an excessively rich or lean system.

Spark: Scan Tool Range -64° to 64°. Displays the amount the PCM commands the spark advance on the IC circuit. The PCM computes the desired spark advance using the following: (1) Engine coolant temperature, (2) Engine speed (RPM), (3) Load, (4) Vehicle speed.

Start Up ECT: Scan Tool Range -39°C to 140°C (-38°F to 284°F). Indicates the Engine Coolant Temperature at the time the engine was started. The PCM uses Start Up ECT for certain DTCs.

Stop Lamp Switch: The scan tool displays Applied or Released. When the brake pedal is depressed, the scan tool displays applied and the stop lamps go on. When the brake pedal is at rest, the scan tool displays Released and the stop lamps go off.

TAC/PCM Communication: The scan tool displays OK or Fault. If the communication between the TAC Module and the PCM is interrupted the scan tool displays Fault. The scan tool displays OK under the normal operating conditions.

TCC/CC Brake Switch: The scan tool displays Applied or Released. This parameter indicates the state of the TCC/CC brake switch circuit input. Open indicates 0 voltage input (brake switch open, brake pedal applied). Closed indicates a B+ voltage input (brake switch closed, brake pedal released). When you apply the vehicle brakes, the scan tool displays Applied. The torque converter clutch and cruise control disengages. When you release the vehicle brakes, the scan tool displays Released. This allows the cruise control to be resumed and the torque converter clutch to engage.

TCC Duty Cycle: The scan tool displays ON or OFF. This parameter is the commanded state of the TCC PWM solenoid. The scan tool indicates Enabled when the commanded state of the solenoid is ON. When the solenoid is not on, the scan tool displays Disabled.

TCC Enable Solenoid: The scan tool displays Enabled or Disabled. When the PCM applies a voltage to the TCC Enable solenoid the scan tool displays Enabled.

Total Misfire Current Count: Scan Tool Range 0-255. The Total Misfire Current Count indicates the total number of cylinder firing events that the PCM detected as being misfires during the last 200 crankshaft revolution sample period.

Total Misfire Failures Since First Fail: Scan Tool Range 0-65,535. The Total Misfire Failures Since First Fail indicates the total number of cylinder firing events that the PCM detected as being misfires since the first failure.

Total Misfire Passes Since First Fail: Scan Tool Range 0-65,535. The Total Misfire Passes Since First Fail indicates the total number of cylinder firing events that the PCM detected as being good since the first fail.

TP Desired Angle: The scan tool displays 0-100 percent. The PCM indicates the desired throttle angle commanded by the vehicle operator.

TP Indicated Angle: The scan tool displays 0-100 percent. The TP Indicated Angle displays in percentage the amount of throttle opening.

TP Sensor 1 Angle: The scan tool displays 0-100 percent. The scan tool displays the amount of throttle opening in percentage. Closed throttle displays 0 percent and wide open throttle displays near 100 percent.

TP Sensor 2 Angle: The scan tool displays 0-100 percent. The scan tool displays the amount of throttle opening in percentage. Closed throttle displays 0 percent and wide open throttle displays near 100 percent.

TP Sensor 1: The scan tool displays 0-5 volts. The scan tool displays the amount of throttle opening in volts. Closed throttle displays about 1 volt and wide open throttle displays above 3.5 volts.

TP Sensor 2: The scan tool displays 5-0 volts. The scan tool displays the amount of throttle opening in volts. Closed throttle displays about 4 volts and wide open throttle displays below 1.5 volts.

TP Sensors Disagree: The scan tool displays Yes or No. When the TAC module receives a signal voltage from one of the Throttle Position Sensors not in proper relationship to the other, the scan tool displays YES. The scan tool displays NO under normal operating conditions.

TP Sensor 1 Out of Range: The scan tool displays Yes or No. If the PCM detects that the voltage is below 1 volt at closed throttle or above 3.5 volts at wide open throttle, the scan tool displays YES. If the voltages are within specifications, the scan tool displays NO.

TP Sensor 2 Out of Range: The scan tool displays Yes or No. If the PCM detects that the voltage is above 4 volts at closed throttle or below 1.5 volts at wide open throttle, the scan tool displays YES. If the voltages are within specifications, the scan tool displays NO.

Traction Control: The scan tool displays Active or Inactive (If equipped). The scan tool displays active if the PCM receives a signal from the Electronic Brake and Traction control Module (EBTCM) requesting torque reduction during a traction control maneuver.

Trans Fluid Temp. (Export only): Scan Tool Range -39°C to 140°C (-38°F to 284°F). The Trans Fluid Temp. sensor parameter displays the temperature of the manual transmission.

Transmission OSS: The scan tool displays a range of 0-8,192 RPM. This parameter indicates the rotational speed of the transmission output shaft.

Transmission Range: Scan tool displays the transaxle gear position.

Vehicle Speed: The scan tool displays km/h and mph. The vehicle speed sensor signal is converted into km/h and mph for display.

VTD Auto Learn Timer: The scan tool displays Active or Inactive. The auto learn timer is the indication if the Vehicle Theft Deterrent (VTD) system is in the learn mode and has not timed out (10 minutes).

VTD Fuel Disable: The scan tool displays Active or Inactive. If the PCM has not received the correct password from the Body Control Module (BCM), the PCM will disable the fuel system, and Active will be displayed on the scan tool. The scan tool displays Inactive under normal running conditions.

VTD Fuel Disable Until Ignition Off: The scan tool displays Yes or No. With the ignition On and a VTD code present the scan tool displays YES. With ignition Off the scan tool displays NO.

Warm Ups w/o Emis. Faults: Scan Tool Range 0-255. This parameter counts the number of warm up cycles without an emission fault present. The counter increments to 255 and resets to 0 unless a fault occurs. If a fault occurs, the counter reverts back to 0 until the fault is corrected. Clearing the information with a scan tool or a loss of power to the PCM also resets the counter to 0.

Warm Ups w/o Non-Emis. Faults: Scan Tool Range 0-255. This parameter counts the number of warm up cycles without a non-emission fault present. The counter increments to 255 and resets to 0 unless a fault occurs. If a fault occurs, the counter reverts back to 0 until the fault is corrected. Clearing information with a scan tool or a loss of power to the PCM also resets the counter to 0.