Scan Tool Data Definitions Part 2
Part2Fuel Tank Vapor Press. Slope: The display shows pressure slope from 0 to 2 in inches of H2O per second. The vapor pressure slope is used during the PCM's diagnosis of the EVAP system. The PCM uses pressure slope to determine the amount of vapor pressure being released from the fuel.
Fuel Trim Cell: Display Shows Fuel Trim Cell range from 0 to 16. Fuel trim cell is dependent upon engine speed and mass air flow readings. A plot of RPM vs. MAF is broken into 16 cells. Fuel trim cell indicates which cell is currently active.
Fuel Trim Learn: Display shows Disabled or Enabled. When conditions are appropriate for enabling long term fuel trim corrections, Fuel Trim Learn will display Enabled. This indicates that the long term fuel trim is responding to the short term fuel trim. If the display shows Disabled then long term fuel trim will not respond to changes in short term fuel trim.
Generator PWM: Display shows Generator F Terminal duty cycle in percent from 0 to 100. The generator is able to produce the desired voltage by varying the duty cycle of the field current. At low engine speeds, the field may have a duty cycle of 90 percent. At higher engine speeds, and lower electrical loads, the duty cycle will be less. The generator produces a PWM signal that is monitored by the PCM. High Elec Load: Display shows Yes or No. Display should show Yes if several accessories are in operation.
HO2S Bank 1 Sensor 1: Display shows bank 1 sensor 1 HO2S voltage from 0 to 1.16.
HO2S Bank 1 Sensor 3: Display shows bank 1 sensor 3 HO2S voltage from 0 to 1.16.
HO2S Bank 2 Sensor 1: Display shows bank 2 sensor 1 HO2S voltage from 0 to 1.16.
HO2S Warm Up Bn 1 Sen. 1: Display shows minutes and seconds from 0:00 to 4:15. This parameter is how much time it takes for the oxygen sensor to start its voltage swings over the rich/lean threshold.
HO2S Warm Up Bn 2 Sen. 1: Display shows minutes and seconds from 0:00 to 4:15. This parameter is how much time it takes for the oxygen sensor to start its voltage swings over the rich/lean threshold.
HO2S X Counts Bank 1: Display shows counts from 0 to 255. This display is the number of times the oxygen sensor voltage crosses over the rich/lean threshold during a one second interval.
HO2S X Counts Bank 2: Display shows counts from 0 to 255. This display is the number of times the oxygen sensor voltage crosses over the rich/lean threshold during a one second interval.
IAC Position: Display shows the commanded IAC pintle position in counts from 0 to 1024. The higher the number of counts, the greater the commanded idle speed. zero is the fully seated position. Idle air control should respond fairly quickly to changes in engine load to maintain desired idle RPM.
IAT: Display shows the temperature of the intake manifold air from -40° to 215°C and -40° to 419°F.
IC Mode: Display shows PCM or ICM. In PCM mode, the PCM controls the ignition timing. The PCM calculates the desired ignition timing based on information the PCM receives from the input sensors. In Ignition Control Module (ICM) mode, the ignition system operates independently from the PCM. The Ignition Control Module maintains a base ignition timing of 10 degrees BTDC and is able to change this ignition timing slightly with increased engine speed. Ignition control mode is in affect whenever an ignition control fault is detected while the engine is running and it will have a noticeable effect on driveability.
Ign. Cycle Center: Display shows counts from 0 to 50. The counts ncrease by one with each On to Off key cycle. When a DTC-sets, the counter is set to zero. If the DTC becomes history, the counter will increment with each key cycle until another DTC is set, or until the key has been cycled at which time the DTC will be erased.
Ignition 0: Displays voltage from 0 to 25.5. This represents the system voltage measured by the PCM at its Ignition 0 feed.
Ignition 1: Display shows voltage from 0 to 25.5. This represents the system voltage measured by the PCM at its ignition feed.
Injector 1 thru 8: Fault Display shows OK or Fault. Scan tool will display fault if the PCM has detected an improper voltage level in any of the fuel injectors circuits to determine it any of the eight injectors are misfiring.
Injector. PWM Bank 1: Display shows injector pulse width for cylinders 1, 3, 5, 7 in milliseconds (ms) from 0 to 99.6.
Injector. PWM Bank 2: Display shows injector pulse width for cylinders 2, 4, 6, 8 in milliseconds (ms) from 0 to 99.6.
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Knock Retard: Display shows knock retard from 0 to 45 degrees. Which indicates the amount of spark advance in degrees that the PCM is removing from the Ignition Control (IC) in response to the Knock Sensor (KS) signal.
KS Active Counter: Display is shown in counts from 0 to 255. Display shows the number of instances of engine detonation detected by the knock sensor in one-eighth of a second from 1 to 255.
Load at Misfire: Display shows load in percent at which DTC P0300 was set. When a misfire is detected, the PCM will store the percent of load at which the misfire occurred.
Loop Status: Display shows OPEN LOOP or CLOSED LOOP. Closed Loop displayed 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 other input sensors. Closed Loop operation should begin when the oxygen sensor becomes active, engine coolant temperature exceeds 5°C (41°F) for more than 30 seconds and the PCM has seen a RPM of 1200 or greater for 10 seconds. At extremely high ambient temperatures or when towing a trailer, it is possible for the system to remain in Open Loop operation to control catalytic converter temperatures.
Long Term FT Bank 1: Display shows counts from 0 to 255 and percentage from -100% to 99%. The normal position for the long term fuel trim is 128 counts or 0%. The long term fuel trim is based on short term fuel trim learned values. It is stored in memory blocks of the long term memory according to MAP and RPM values. A count greater than 128 or a percentage greater than 0% indicates that time is being added to the injector pulse width, increasing the amount of fuel to the engine. A count less than 128 or a percentage less than 0% indicates time is being subtracted from the injector pulse width, reducing the amount fuel to the engine.
Long Term FT Bn 2: Display shows counts from 0 to 255 and percentage from -100% to 99%. The normal position for the long term fuel trim is 128 counts or 0%. The long term fuel trim is based on short term fuel trim learned values. It is stored in memory blocks of the long term memory according to MAP and RPM values. A count greater than 128 or a percentage greater than 0% indicates that time is being added to the injector pulse width, increasing the amount of fuel to the engine. A count less than 128 or a percentage less than 0% indicates time is being subtracted from the injector pulse width, reducing the amount fuel to the engine.
L/R Switch Bank 1 Sen. 1: Display shows counts from 0 to 65535. This displays the number of counts when the HO2S voltage swings above the rich mean threshold.
L/R Switch Bank 2 Sen. 1: Display shows counts from 0 to 65535. This displays the number of counts when the HO2S voltage swings above the rich mean threshold.
L/R Transition Time Bn 1 Sen. 1: Display shows time in milliseconds from 0.0 to 3187.5 ms. Display is the time for the HO2S voltage to change from the lean threshold to the rich threshold.
L/R Transition Bn 2 Sen. 1: Display shows time in milliseconds from 0.0 to 3187.5 ms. Display is the time for the HO2S voltage to change from the lean threshold to the rich threshold.
MAF: Display shows the amount of airflow entering the engine in grams per second (g/s) from 0 to 655. The scan tool will display 0 gms/sec only until 4X reference pulses are received,cranking or running. The PCM updates the MAF sensor display only after 4X reference pulses have been received during an ignition cycle. If during an ignition cycle the vehicle were to stall the MAF display would indicate the last airflow reading obtained while 4X reference pulses were present. If no airflow is monitored by the PCM while the vehicle is running the MAF display will default to 1.2 grams per second.
MAF Frequency: Display shows the amount of air passing the MAF sensor and entering the engine. This display indicates the airflow measured in frequency. The frequency value is converted by the PCM to grams per second.
MAP: Display shows manifold pressure in Kilo Pascals (kPa) from 10 to 105. At key ON,engine not running, the MAP value will reflect barometric pressure.To check for an accurate MAP reading multiply your local barometric pressure by 3.386 to obtain a map value that should be within 2 kPa of displayed value at key ON, engine not running.
MIL: Display shows ON or OFF. The MIL (Service Engine Soon) is controlled by the PCM and is used to indicate that the PCM has detected a problem that affects vehicle emissions, driveability or could cause powertrain damage.
MIL Driver: Display shows OK, Open/Short, Over Current. The PCM monitors output driver (ODM) A output #1 for an open or shorted condition if one of the conditions exists the fault line will go low. The scan tool will display the condition that is present.
Misfire Current #1 (thru) #8: Display shows Misfire Current counters increment at a rate according to the number of possible misfires being detected 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 #1 (thru) #8: Display shows counts from 0 to 65535. 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.
Misfire Cycle Delay Counter: Display shows counts from 0 to 255. If the misfire test is interrupted, due to the vehicle coming outside the test conditions for P0300, this display will show the number of engine cycles left before the test is re-enabled and data collection will resume.
Non-Driven Wheel Speed: Display shows MPH / km/h from 0 to 158 MPH, 0 to 255 km/h. This display is the non-drive (rear) wheel speed sent to the EBTCM, used for traction control and Anti-Lock braking and is monitored by the PCM.
Number of Failed Emission Misfire Tests out of Last 16: The display shows a value of 0 to 16.
Odometer: Display shows miles from 0 to 1677722. This display is the actual vehicle miles stored in the PCM.
Outside Air Temp: Display shown 0°C (40° F) to 102°C (215°F).This is the outside temperature sent from the HVAC to the PCM across the data link.
PNP: Display shows P-N or -R-OD21. GP-N- displayed indicates the gear select lever is in Park or Neutral. -ROD21 displayed indicates the gear select lever is in Reverse, Drive, or Low Range.