Understanding your vehicle’s health is crucial for every car owner and mechanic. Modern vehicles are equipped with sophisticated onboard diagnostic systems, and accessing live data is key to pinpointing issues and ensuring optimal performance. The BlueDriver OBD2 Diagnostic Scan Tool stands out as a powerful tool for accessing this real-time information. This article provides an in-depth look at the live data parameters available through BlueDriver, helping you understand what each data point means and how it can be used for effective vehicle diagnostics.
Decoding Vehicle Operation Parameters with BlueDriver
BlueDriver provides a wealth of information regarding your vehicle’s operational status. These parameters offer a snapshot of how your engine and related systems are performing in real-time.
Engine RPM
Engine RPM (Revolutions Per Minute) measures how fast your engine’s crankshaft is rotating. This is a fundamental parameter for understanding engine speed and is critical for diagnosing issues related to idling, acceleration, and overall engine performance.
Vehicle Speed
Vehicle Speed is a straightforward parameter indicating the current speed of your vehicle. This data point is essential for verifying speedometer accuracy and diagnosing speed-related sensor problems.
Engine Coolant Temperature
Engine Coolant Temperature reflects the temperature of the engine coolant, typically measured at the cylinder head or before the radiator. Monitoring coolant temperature is vital to prevent overheating and diagnose cooling system malfunctions. BlueDriver may also report a second coolant temperature sensor (ECT 2) on some vehicles, providing more detailed thermal insights.
Engine Oil Temperature
Engine Oil Temperature monitors the temperature of the engine oil. This parameter is crucial for assessing engine lubrication and thermal management, especially under heavy load or in extreme conditions. Sensor location can vary, often near the oil filter.
Ambient Air Temperature
Ambient Air Temperature measures the air temperature surrounding the vehicle. This reading is typically slightly lower than the intake temperature and is useful for understanding the external conditions affecting engine performance.
Barometric Pressure
Barometric Pressure reflects the atmospheric pressure around the vehicle, presented as an absolute value. Typically around 101.3 kPa or 14.7 psi at sea level, this value varies with altitude and weather conditions. It’s important for the engine control module (ECM) to adjust for air density changes.
Accelerator Pedal Position
Accelerator Pedal Position indicates the position of the driver’s accelerator pedal. BlueDriver may display readings from up to three sensors (Accelerator Pedal Position D, E, and F), offering redundancy and accuracy in pedal input measurement.
Relative Accelerator Pedal Position
Relative Accelerator Pedal Position is an adjusted accelerator pedal position, accounting for the vehicle’s learned behavior over time. This value may not always reach 100% when the pedal is fully pressed due to scaling and adaptive learning. It might also be an average of multiple sensors.
Commanded Throttle Actuator
Commanded Throttle Actuator shows the throttle position requested by the ECM based on the accelerator pedal input. This parameter helps in understanding the electronic throttle control system’s response to driver commands.
Relative Throttle Position
Relative Throttle Position indicates the throttle position relative to the “learned” closed position. This is important because carbon buildup or other factors can alter the throttle’s behavior over time. For instance, if carbon buildup causes a 5% opening when “closed,” the absolute throttle position might read 5%, while the relative position accurately reads 0%.
Absolute Throttle Position
Absolute Throttle Position reflects the actual opening of the throttle, from 0% (fully closed) to 100% (fully open). BlueDriver can report data from up to four throttle position sensors (TPS A/1, TPS B/2, TPS C/3, TPS D/4) depending on the vehicle.
Control Module Voltage
Control Module Voltage displays the input voltage at the Engine Control Module (ECM). With the engine off and ignition on, it shows battery voltage; with the engine running, it reflects alternator voltage. This is critical for diagnosing electrical system health.
Hybrid Battery Pack Remaining Life
Hybrid Battery Pack Remaining Life, also known as State of Charge (SOC), shows the total charge percentage left in a hybrid vehicle’s battery pack. BlueDriver provides this overall value, though individual cell data isn’t standard OBD2 information.
Hybrid/EV Vehicle System Status
Hybrid/EV Vehicle System Status reports several key parameters for hybrid and electric vehicles:
- Hybrid/EV Charging State: Indicates whether the system is in Charge Sustaining Mode (CSM) – maintaining charge, or Charge Depletion Mode (CDM) – reducing charge. Non-PHEVs will always show CSM.
- Hybrid/EV Battery Voltage: Voltage of the hybrid/EV battery, ranging from 0 to 1024V.
- Hybrid/EV Battery Current: Current flow to or from the battery, from -3300 to 3300 Amps. Negative values indicate charging.
Calculated Engine Load Value
Calculated Engine Load Value is a percentage representing the current engine torque output relative to the maximum available torque. 100% indicates Wide Open Throttle (WOT), while 0% is at key-on engine-off.
Absolute Load Value
Absolute Load Value is a normalized percentage indicating air mass intake per intake stroke relative to the maximum possible at standard temperature and pressure. Naturally aspirated engines typically range from 0 to 95%, while turbo/supercharged engines can reach up to 400%.
Driver’s Demand Engine – Percent Torque
Driver’s Demand Engine – Percent Torque is the ECM’s requested percentage of maximum torque based on driver input (accelerator pedal, cruise control) and transmission status, excluding external factors like traction control.
Actual Engine – Percent Torque
Actual Engine – Percent Torque, also called Indicated Torque, shows the current percentage of total available engine torque, including brake torque and the torque needed to overcome engine friction.
Engine Friction – Percent Torque
Engine Friction – Percent Torque represents the percentage of maximum torque needed to overcome internal engine friction (components, fluids, pumps, intake, exhaust, alternator, emissions equipment) at no load. It excludes accessories like power steering or AC compressors.
Engine Reference Torque
Engine Reference Torque is the factory-set torque rating of the engine, considered 100% for torque percentage parameters. It doesn’t reflect changes from wear, upgrades, or tuning.
Engine Percent Torque Data
Engine Percent Torque Data is used when conditions change the reference torque, like altitude affecting fuel mapping. It can specify up to five different maximum torque ratings, though the reasons for changes aren’t provided and may require a factory manual.
Auxiliary Input/Output
Auxiliary Input/Output is a composite parameter reporting (if supported):
- Power Take Off (PTO) Status: On or Off.
- Automatic Transmission Status: Park/Neutral or Drive/Reverse.
- Manual Transmission Neutral Status: Neutral/Clutch In or In Gear.
- Glow Plug Lamp Status: Indicator On or Off.
- Recommended Transmission Gear: 1 through 15.
Support for this is rare; transmission status is usually in enhanced live data.
Exhaust Gas Temperature (EGT)
Exhaust Gas Temperature (EGT) can report temperatures at various points in the exhaust system for each bank:
- Sensor #1 – Post-turbo
- Sensor #2 – Post-catalytic converter (cat)
- Sensor #3 – Post-Diesel Particulate Filter (DPF)
- Sensor #4 – Possibly after NOx control equipment
Locations vary; refer to the factory manual for specifics.
Engine Exhaust Flow Rate
Engine Exhaust Flow Rate measures exhaust flow in kg/hr or lbs/hr upstream of the aftertreatment system, averaged over 1000ms.
Exhaust Pressure
Exhaust Pressure is reported as an absolute pressure value. Engine off, it should read ambient atmospheric pressure. It may report data from one or two exhaust banks; check the factory manual for sensor locations.
Manifold Surface Temperature
Manifold Surface Temperature measures the temperature on the outer surface of the exhaust manifold.
Timing Advance for #1 cylinder
Timing Advance for #1 cylinder is the crankshaft rotation angle in degrees Before Top Dead Center (BTDC) when the spark plug for cylinder #1 fires. Positive values are BTDC; negative are After Top Dead Center (ATDC).
Engine Run Time
Engine Run Time reports:
- Total engine run time in seconds.
- Total engine idle time in seconds (defined by no throttle input, low RPM, PTO inactive, low vehicle speed).
- Total run time with PTO engaged (if equipped).
Run Time Since Engine Start
Run Time Since Engine Start is the time in seconds since the engine was last started.
Time Run with MIL On
Time Run with MIL On is the engine run time since the Check Engine Light (MIL) was activated. It stops increasing at 65,535 minutes (roughly 45 engine-days) and continues on hybrids/stop-start vehicles as long as ignition is on.
Distance Traveled while MIL is Activated
Distance Traveled while MIL is Activated is the distance driven since the MIL last illuminated. It resets when codes are cleared or the battery is disconnected.
Time since Trouble Codes Cleared
Time since Trouble Codes Cleared is the engine run time since codes were last cleared. It stops at 65,535 minutes and continues on hybrids/stop-start vehicles with ignition on.
Distance Traveled Since Codes Cleared
Distance Traveled Since Codes Cleared is the distance traveled since engine codes were cleared. Clearing non-engine codes doesn’t reset this.
Warm-ups Since Codes Cleared
Warm-ups Since Codes Cleared counts engine warm-up cycles since codes were cleared. A warm-up cycle is defined by a coolant temperature increase of at least 22°C/40°F after startup and reaching at least 70°C/170°F (or 60°C/140°F for diesel). It stops at 255 cycles. Non-engine code clearing doesn’t reset this.
Fuel & Air Data Parameters for Diagnostic Insight
BlueDriver’s live data capabilities extend to fuel and air system parameters, essential for diagnosing engine efficiency and combustion issues.
Fuel System Status
Fuel System Status indicates whether the vehicle is in ‘open’ or ‘closed’ loop mode. Open loop uses pre-programmed air-fuel ratios, while closed loop uses O2 sensor feedback for adjustments. BlueDriver reports status for two fuel systems (A & B), which may represent different fuel types (like CNG & diesel) rather than engine banks. Most vehicles use only one fuel system.
Oxygen Sensor Voltage
Oxygen Sensor Voltage is the voltage output of the O2 sensors. Fluctuations in voltage are critical for understanding air-fuel mixture adjustments. Refer to resources like Walker’s O2 Sensor Training Guide for interpretation.
Oxygen Sensor Equivalence Ratio
Oxygen Sensor Equivalence Ratio, also known as Lambda, is another O2 sensor reading. It indicates the ratio of actual air-fuel mixture to the ideal stoichiometric mixture.
Oxygen Sensor Current
Oxygen Sensor Current is similar to voltage, with 0mA indicating a balanced air-fuel ratio, positive current for lean mixtures, and negative for rich mixtures.
Short Term Fuel Trim
Short Term Fuel Trim is the fuel injection rate adjustment based on rapid O2 sensor data changes. Negative trim means a rich condition (less fuel needed), positive means lean. Bank and sensor numbers indicate engine side and pre/post-catalytic converter sensor locations. Short term fuel trim works with long term fuel trim for net injection correction. Post-cat sensor trim may be displayed as 99.2% on vehicles that don’t use it.
Long Term Fuel Trim
Long Term Fuel Trim is similar to short term trim but adjusts more slowly, reflecting learned vehicle behavior over time. Bank and sensor numbers are as in short term trim. Post-cat sensor trim may also be 99.2% when unused.
Image alt text: Example of Long Term Fuel Trim data displayed in a graph format, illustrating fuel system adjustments over time.
Commanded Equivalence Ratio
Commanded Equivalence Ratio is the fuel-air ratio requested by the ECM, displayed as a lambda value (>1 lean, <1 rich, ~1 ideal). Vehicles with wide-range O2 sensors show this in both open and closed loop modes. Conventional O2 sensor vehicles show it only in open loop, displaying 1.0 in closed loop.
Mass Air Flow Rate
Mass Air Flow Rate (MAF) measures the air flow rate through the intake, in g/s or lb/min. On turbocharged vehicles, the MAF sensor is upstream of the turbo.
Intake Air Temperature
Intake Air Temperature (IAT) is the temperature of air in the intake. Turbocharged vehicles may have two IAT sensors (pre- and post-turbo). Some vehicles may have dual intakes with sensors for each bank. IAT should be slightly above ambient temperature normally.
Intake Manifold Absolute Pressure
Intake Manifold Absolute Pressure (MAP) is the pressure inside the intake manifold, an absolute pressure value. For turbo applications, it’s pressure after the turbo/intercooler. At idle, it’s slightly below ambient pressure, and at key-on engine-off, it’s ambient. To get gauge pressure, subtract ambient pressure.
Fuel Pressure (Gauge)
Fuel Pressure (Gauge) is the fuel pressure value as a gauge pressure. 0 indicates atmospheric pressure.
Fuel Rail Pressure
Fuel Rail Pressure is the pressure in the fuel rail, displayed as gauge pressure (0 psi/kPa is atmospheric).
Fuel Rail Pressure (Absolute)
Fuel Rail Pressure (Absolute) is the fuel rail pressure as an absolute pressure value. When not pressurized, it reads ambient pressure (roughly 14.7 psi or 101.3 kPa).
Fuel Rail Pressure (relative to manifold vacuum)
Fuel Rail Pressure (relative to manifold vacuum) is the fuel pressure relative to the intake manifold pressure.
Alcohol Fuel %
Alcohol Fuel % is the ethanol/alcohol content measured by the ECM, as a percentage. E85 blend would read 85%.
Fuel Level Input
Fuel Level Input is the percentage of maximum fuel tank capacity remaining.
Engine Fuel Rate
Engine Fuel Rate is the near-instantaneous fuel consumption rate in Liters or Gallons per hour, calculated by the ECM based on fuel used in the last 1000 ms. It doesn’t include fuel for diesel aftertreatment.
Cylinder Fuel Rate
Cylinder Fuel Rate is the calculated fuel injected per cylinder per intake stroke, in mg/stroke.
Fuel System Percentage Use
Fuel System Percentage Use displays the percentage of total fuel usage per cylinder bank, up to four banks. It can show data for two separate fuel systems if supported.
Fuel Injection Timing
Fuel Injection Timing is the crankshaft rotation angle in degrees BTDC when fuel injection starts. Positive angles are BTDC, negative are ATDC.
Fuel System Control
Fuel System Control reports diesel fuel system status for systems 1 & 2:
- Fuel pressure control: Closed or open loop.
- Fuel injection quantity: Closed or open loop.
- Fuel injection timing: Closed or open loop.
- Idle fuel balance/contribution: Closed or open loop.
Closed loop means sensor feedback is used for fine-tuning. System 2 may be unused on many vehicles.
Fuel Pressure Control System
Fuel Pressure Control System displays data for up to two fuel rails:
- Commanded rail pressure.
- Actual rail pressure.
- Temperature.
Pressure is gauge pressure (0 is atmospheric). Check the factory manual for sensor locations.
Injection Pressure Control System
Injection Pressure Control System (ICP) is used in some diesels with oil-actuated fuel injection. It monitors oil pressure in the high-pressure oil rail. Parameters include:
- Commanded Control Pressure Rail A.
- Actual Pressure Rail A.
- Commanded Control Pressure Rail B.
- Actual Pressure Rail B.
Boost Pressure Control
Boost Pressure Control for one or two turbochargers shows:
- ECM commanded boost pressure.
- Actual boost pressure.
All values are absolute pressure. Gauge pressure is absolute pressure minus atmospheric pressure. It also shows boost control system operating mode:
- Open Loop – No sensor feedback, no faults.
- Closed Loop – Using feedback, no faults.
- Fault Present – Boost data unreliable.
Turbocharger RPM
Turbocharger RPM measures turbine RPM for one or both turbos. Maximum value is 655,350 rpm. Graph range adjustment might be needed for monitoring.
Turbocharger Temperature
Turbocharger Temperature reports temperatures for one or both turbos:
- Compressor inlet temperature (pre-turbo).
- Compressor outlet temperature (post-turbo, higher value).
- Turbine inlet temperature (pre-turbine).
- Turbine outlet temperature (post-turbine).
Charge air temperatures range from -40 to 215°C; exhaust temperatures from -40 to 6513.5°C.
Turbocharger Compressor Inlet Pressure Sensor
Turbocharger Compressor Inlet Pressure Sensor measures pressure at the turbo inlet, for one or two turbos. It’s an absolute pressure value. Roughly 14.7 psi / 101.3 kPa is atmospheric pressure.
Variable Geometry Turbo (VGT) Control
Variable Geometry Turbo (VGT) Control for turbos with adjustable vanes reports:
- Commanded VGT Position (vane position requested).
- Actual VGT Vane Position.
- VGT Control Status: Closed or Open Loop, or Fault State (data unreliable).
0% vane position is maximum bypass; 100% redirects maximum exhaust gas for boost.
Wastegate Control
Wastegate Control for electronic wastegates reports:
- Commanded wastegate position (0% fully closed, 100% maximum bypass).
- Actual wastegate position (0% to 100%).
Charge Air Cooler Temperature (CACT)
Charge Air Cooler Temperature (CACT) measures intercooler air charge temperature with up to four sensors:
- Bank 1 Sensor 1.
- Bank 1 Sensor 2.
- Bank 2 Sensor 1.
- Bank 2 Sensor 2.
SAE/OBDII standards don’t define sensor mapping; refer to the factory manual.
Emissions Control Equipment Information for a Cleaner Diagnosis
BlueDriver’s diagnostic capabilities also extend to emissions control systems, providing vital data for ensuring environmental compliance and diagnosing related malfunctions.
Commanded EGR
Commanded EGR shows the requested opening percentage of the Exhaust Gas Recirculation (EGR) valve by the ECM (0% fully closed, 100% fully open).
EGR Error
EGR Error is the percentage difference between commanded and actual EGR valve opening. If commanded EGR is 0%, EGR error will be 0% if actual is also 0%, or 99.2% if actual EGR is not 0% (indicating “undefined” or not applicable). Calculated as (actual – commanded) / commanded.
Commanded Diesel Intake Air Flow Control
Commanded Diesel Intake Air Flow Control, also known as EGR Throttle, is used in some newer diesels to create intake vacuum for EGR. It displays:
- Commanded EGR throttle plate position (closed to 100% open).
- Actual EGR throttle position.
- Commanded position of a secondary EGR throttle (if present).
- Actual position of secondary EGR throttle.
Exhaust Gas Recirculation Temperature
Exhaust Gas Recirculation Temperature reports up to four EGR temperature values:
- EGRTA – Bank 1 Pre-Cooler.
- EGRTB – Bank 1 Post-Cooler.
- EGRTC – Bank 2 Pre-Cooler.
- EGRTD – Bank 2 Post-Cooler.
EVAP System Vapor Pressure
EVAP System Vapor Pressure is the gauge pressure of the Evaporative Emission Control System (EVAP), measured by a sensor in the fuel tank or EVAP line. Check the factory manual for location.
Absolute Evap System Vapor Pressure
Absolute Evap System Vapor Pressure is the absolute pressure of the EVAP system. Absolute pressure around 14.7 psi or 101.3 kPa indicates 0 gauge pressure.
Commanded Evaporative Purge
Commanded Evaporative Purge is the EVAP purge flow rate requested by the ECM (0% fully closed, 100% maximum).
Catalyst Temperature
Catalyst Temperature is the temperature of the catalytic converter. Bank # indicates engine side, and Sensor # indicates pre (#1) or post (#2) cat sensor.
Diesel Aftertreatment Status
Diesel Aftertreatment Status reports on the Diesel Particulate Filter (DPF) and NOx adsorber systems:
- Current DPF Regeneration Status: Active/Not Active.
- Current DPF Regeneration Type: Passive/Active.
- NOx Adsorber Regen Status: Active/Not Active.
- NOx Adsorber Desulferization Status: Active/Not Active.
- Normalized Trigger for DPF Regen: Percentage to next regen (0% just completed, 100% about to start).
- Average Time Between DPF Regens: Exponential weighted moving average time over last 6 regens.
- Average Distance Between DPF Regens: Exponential weighted moving average distance over last 6 regens.
Diesel Exhaust Fluid Sensor Data
Diesel Exhaust Fluid Sensor Data reports:
- DEF Type: Urea too high/low, diesel, proper DEF, sensor fault.
- DEF Concentration: Urea concentration (ideally ~32.5%).
- DEF Tank Temperature.
- DEF Tank Level: May not be progressive; see “NOx Control System” for details.
Diesel Particulate Filter (DPF)
Diesel Particulate Filter (DPF) parameters:
- Inlet pressure.
- Outlet pressure.
- Differential pressure across the filter.
Increased differential pressure indicates soot buildup. Bank 1 vs 2 indicates engine side.
Diesel Particulate Filter (DPF) Temperature
Diesel Particulate Filter (DPF) Temperature reports inlet and outlet temperatures for each exhaust bank:
- Inlet temperature.
- Outlet temperature.
Bank 1 vs 2 indicates engine side.
NOx Sensor
NOx Sensor reports NOx concentration in ppm for:
- Bank 1 Sensor 1.
- Bank 1 Sensor 2.
- Bank 2 Sensor 1.
- Bank 2 Sensor 2.
Bank # indicates engine side; Sensor # is before (#1) or after (#2) NOx adsorber.
NOx Control System
NOx Control System data on NOx adsorption:
- Average Reagent Consumption Rate: Over previous 48 hours or last 15L consumed. 0 when key-on engine-off.
- Average Demanded Consumption Rate: ECM commanded rate over same period. 0 when key-on engine-off.
- Reagent Tank Level: 0 to 100%. May have discrete measurement points; see description for non-progressive readings.
- NOx Warning Indicator Time: Engine run time in seconds since NOx/SCR warning light activation. Stops increasing when light is off, resets after 9600 hours without light.
NOx Sensor Corrected Data
NOx Sensor Corrected Data is NOx concentration in PPM with learned adjustments and offsets.
NOx NTE Control Area Status
NOx NTE Control Area Status reports:
- Vehicle operation inside/outside NOx control area.
- Operation inside manufacturer’s “carve-out” (exemption) region.
- NTE-related deficiency within NOx operating control area.
PM Sensor Bank 1 & 2
PM Sensor Bank 1 & 2 reports for each bank:
- Particulate matter sensor active: yes/no.
- Particulate matter sensor regenerating: yes/no.
- Particulate matter sensor value: 0% (clean) to 100% (regen required).
Particulate Matter (PM) Sensor
Particulate Matter (PM) Sensor is soot concentration measured by PM sensors on banks 1 & 2, in mg/m3.
PM NTE Control Area Status
PM NTE Control Area Status reports:
- Vehicle operation inside/outside PM control area.
- Operation inside manufacturer’s “carve-out” region.
- NTE-related deficiency within PM operating control area.
SCR Inducement System
SCR Inducement System reports SCR inducement status and reasons (low reagent, incorrect reagent, abnormal consumption, excessive NOx). Also shows if inducement occurred in past 10,000 km blocks up to 40,000 km and total distance traveled with inducement active per block.
NOx Warning And Inducement System
NOx Warning And Inducement System reports warning/inducement levels (Level 1-3 severity) and statuses (Inactive, Enabled but not active, Active, Not supported). Also reports total engine hours for:
- Incorrect reagent use.
- Incorrect reagent consumption rate.
- Reagent dosing interruption.
- Active DTC for incorrect EGR operation.
- Active DTC for incorrect NOx control equipment.
Engine Run Time for AECD
Engine Run Time for AECD reports total time each “Emissions Increasing Auxiliary Emissions Control Device” (AECD) was active. Timers are not resettable. May show one or two timers per AECD:
- TIME1: Total run time AECD active (or run time with up to 75% emissions control inhibition).
- TIME2: Max value “not used” (or run time with >75% emissions control inhibition).
Understanding these comprehensive live data parameters available through the BlueDriver OBD2 Diagnostic Scan Tool empowers you to perform detailed vehicle diagnostics. Whether you are a professional technician or a car enthusiast, leveraging this data is essential for maintaining vehicle health, optimizing performance, and addressing potential issues proactively.
