Scan Tool Data Definitions 2

SCAN TOOL DATA DEFINITIONS

Generator F-Terminal Signal: The scan tool displays percentage.

Generator L-Terminal Signal Command: The scan tool displays OFF/ON.

HO2S 1: The scan tool displays a range of 0-1,106 mV.

HO2S 2: The scan tool displays a range of 0-1,106 mV.

HO2S 1 Heater Current: This parameter displays the current through the control module when the HO2S 1 heater is commanded ON by the control module. HO2S 1 Heater Current is a range of values indicating a low current when the heater circuit resistance is high to a high current when the heater circuit resistance is low.

HO2S 2 Heater Current: This parameter displays the current through the control module when the HO2S 2 heater is commanded ON by the control module. HO2S 2 Heater Current is a range of values indicating a low current when the heater circuit resistance is high to a high current when the heater circuit resistance is low.

IAT Sensor: The scan tool displays a range of -40 to +151°C (-40 to +303°F). The powertrain control module (PCM) converts the resistance of the intake air temperature (IAT) sensor to degrees. The PCM uses the IAT in order to adjust fuel delivery and spark timing according to incoming air density.

Ignition 1 Signal: This parameter displays the voltage measured at the ignition 1 circuit of the control module. Voltage is applied to the control module when the ignition switch is in the ignition 1 position.

Injector PWM: The scan tool displays 0-999.9 mS. Indicates the base pulse width modulation (PWM) or ON time of the fuel injectors in milliseconds. When the engine load is increased, the injector pulse width will increase.

Injector 1-6 Command: The scan tool displays 0-999.9 mS. Indicates the PCM command on the fuel injectors. The higher the number the longer the PCM is commanding the fuel injectors ON.

Knock Retard: The scan tool displays a range of 0-16 degrees. Knock retard indicates the amount of spark the powertrain control module (PCM) removes from the spark advance in response to the signal from the knock sensors.

Long Term FT: The scan tool displays percentage. The powertrain control module (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. A positive value significantly more than 0 percent indicates that a lean condition exists and the PCM compensates by adding fuel. Fuel trim values at maximum authority indicates an excessively rich or lean system.

Loop Status: The scan tool displays Open or Closed. Closed Loop indicates that the powertrain control module (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 throttle position (TP) sensor, engine coolant temperature (ECT) sensor inputs only.

MAP Sensor: The scan tool displays a range of 10-105 kPa and 0.00-5.0 volts. The manifold absolute pressure (MAP) sensor measures the absolute pressure in the intake manifold.

Medium Resolution Resync Counter: The scan tool displays 0-255 counts. The medium resolution resync counter displays the number of times the PCM had to resync the crankshaft position (CKP) sensor.

MIL Command: This parameter displays the commanded state of the malfunction indicator lamp (MIL) control circuit. The malfunction indicator lamp should be on when the scan tool indicates the MIL Command is On. The malfunction indicator lamp should be off when the scan tool indicates the MIL Command is Off. The control module will command the MIL On when the ignition is ON with the engine OFF in order to perform a bulb check.

Misfire Current Cyl. #1 - #6: The scan tool displays a range of 0-255 counts. The misfire current counters increment at a rate according to the number of possible misfires the powertrain control module (PCM) detects on each cylinder during the last 200 cylinder firing events. The counters may normally display some activity, but the activity should be nearly equal for all the cylinders.

Misfire History Cyl. #1 - #6: The scan tool displays a range of 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 cylinder firing events.

Number Of DTC(s): This parameter indicates the total number of current diagnostic trouble codes (DTCs) set. These current DTCs set does not necessarily mean that the malfunction indicator lamp (MIL) is illuminated.

PCM/VCM in VTD Fail Enable: The PCM displays Yes or No. The scan tool displays Yes if the body control module (BCM) and the powertrain control module (PCM) lose communications with each other after the BCM sends the correct password. The scan tool displays No if the BCM is communicating the correct password to the PCM.

Power Enrichment: The scan tool displays Active/Inactive. The scan tool indicates when power enrichment mode is active (moderate to heavy acceleration). Helpful in diagnosing DTC P1171.

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.

Short Term FT: The scan tool displays percentage. The short term fuel trim represents a short term correction to fuel delivery by the powertrain control module (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 mainly remains 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 stays mainly above the 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: The scan tool displays a range of -64 degrees to +64 degrees. The scan tool displays the amount of degrees the powertrain control module (PCM) commands the spark advance. The PCM computes the desired spark advance using the following:
1. Engine coolant temperature (ECT)
2. Engine speed (RPM),
3. Load
4. Vehicle speed

The PCM adjusts the timing.

Start Up ECT: The scan tool displays a range of -40 to +151°C (-40 to +303°F). The scan tool displays the engine coolant temperature (ECT) at the time the engine was started. The powertrain control module (PCM) uses start-up ECT for certain diagnostic trouble codes (DTCs).

Starter Relay Command: This parameter displays the commanded state of the starter relay control circuit. The scan tool will display ON or OFF. ON indicates the starter relay control circuit is being grounded by the control module, allowing voltage to the starter. OFF indicates the starter relay is not being commanded ON by the control module.

TCC Enable Solenoid Command: This parameter displays the commanded state of the torque converter clutch (TCC) solenoid control circuit. The scan tool will display ON or OFF. ON indicates the TCC solenoid control circuit is being grounded by the control module, operating the torque converter. OFF indicates the TCC solenoid is not being commanded on by the control module.

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

TP Indicated Angle: This parameter displays the angle of the throttle position (TP) in percent. This information is calculated by the control module using the signals from the throttle position sensors. The scan tool will display a low percentage when the throttle plate is closed. The scan tool will display a high percentage when the throttle plate is fully open.

TP Sensor 1: This parameter displays the voltage signal sent to the control module from the sensor used to monitor the position of the throttle plate. This parameter is for sensor 1 of the throttle position (TP) sensor assembly. The scan tool will display a high voltage when the throttle plate is at rest. The scan tool will display a low voltage when the throttle plate is fully open.

TP Sensor 1: This parameter displays the angle of the throttle position (TP) sensor 1 in percent. This information is calculated by the control module using the signal from the throttle position sensor 1. The scan tool will display a low percentage when the throttle plate is closed. The scan tool will display a high percentage when the throttle plate is fully open.

TP Sensors 1 and 2: This parameter displays the results of a control module test that compares the signals from the throttle position (TP) sensors 1 and 2. The scan tool will display Agree when the signal from TP sensor 1 corresponds with the signal from TP sensor 2. The scan tool will display Disagree when the signal from TP sensor 1 conflicts with the signal from TP sensor 2.

TP Sensor 2: This parameter displays the voltage signal sent to the control module from the sensor used to monitor the position of the throttle plate. This parameter is for sensor 2 of the throttle position (TP) sensor assembly. The scan tool will display a low voltage when the throttle plate is at rest. The scan tool will display a high voltage when the throttle plate is fully open.

TP Sensor 2: This parameter displays the angle of the throttle position (TP) sensor 2 in percent. This information is calculated by the control module using the signal from the throttle position sensor 2. The scan tool will display a low percentage when the throttle plate is closed. The scan tool will display a high percentage when the throttle plate is fully open.

Traction Control Signal: The scan tool displays Active / Inactive. This parameter indicates the status of the traction control system.

TR Sw: The scan tool displays High/Low. A transaxle mounted switch is used as an input to let the PCM know what position the gear select lever is in. The scan tool status will switch from Park, Reverse, Neutral, Drive 4, Drive 3, Drive 2, Drive 1.

TWC Temperature Calculated: Represents the calculated temperature of the catalytic converter. Useful for determining if the Catalyst Monitor Test has run.

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

VTD Fuel Disable: The scan tool displays Active/Inactive. If the powertrain control module (PCM) has not received the correct password from the body control module (BCM), the PCM disables the fuel system and the scan tool displays Active. The scan tool displays Inactive under normal operating conditions.

VTD Password: The scan tool displays OK, or Incorrect. This parameter indicates the validity of the vehicle theft deterrent password.

VTD Auto Learn Timer: The scan tool displays Active/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.

VTD Fuel Disable Until Ignition Off: The scan tool displays Yes or No. With the ignition ON and a vehicle theft deterrent (VTD) code present, the scan tool displays Yes.