Understanding your vehicle’s health is crucial for preventative maintenance and timely repairs. Modern vehicles are equipped with sophisticated onboard diagnostic systems, and tools like BlueDriver OBD2 scanners provide access to a wealth of real-time data. This guide delves into the standard OBDII live data parameters accessible through BlueDriver, offering insights into what these readings mean and how they can help you understand your car better.
While you might be looking into Bluedriver Obd2 Reading Air Conditioner related data, it’s important to note that standard OBD2 protocols primarily focus on engine and emissions-related parameters. Direct air conditioner system readings are generally not part of the standard OBD2 data set. However, monitoring engine performance with BlueDriver can indirectly help diagnose issues that might affect or be affected by the air conditioning system, such as engine load and temperature changes when the AC is engaged.
This article will explore the various categories of OBDII live data available through BlueDriver, helping you interpret the information and utilize it for effective vehicle diagnostics. Keep in mind that the actual data points supported can vary depending on your vehicle’s year, make, and model. You can always verify compatibility using BlueDriver’s official Compatibility Tool.
Vehicle Operation Parameters
This section covers essential data points related to the fundamental operation of your vehicle’s engine and related systems.
Engine RPM
Description: Engine Revolutions Per Minute. This reading indicates how fast your engine’s crankshaft is rotating.
Importance: RPM is a fundamental engine parameter. It’s crucial for understanding engine load, idle stability, and overall engine performance. Unusual RPM readings can indicate various issues, from vacuum leaks to sensor malfunctions.
Vehicle Speed
Description: The current speed of your vehicle.
Importance: While seemingly basic, vehicle speed data from the OBD2 system is used by various onboard systems, including cruise control and transmission control. Discrepancies between the speedometer and OBD2 speed readings can point to sensor or instrument cluster issues.
Engine Coolant Temperature
Description: The temperature of the engine coolant, typically measured at the cylinder head or before the radiator. Some vehicles may have a second coolant temperature sensor (ECT 2) at a different location.
Importance: Coolant temperature is vital for engine health. Overheating can cause severe engine damage. Monitoring coolant temperature helps ensure the engine is running within its optimal temperature range.
Engine Oil Temperature
Description: The temperature of the engine oil, with sensor location varying by vehicle.
Importance: Oil temperature is another key indicator of engine health. High oil temperatures can degrade oil quality and lead to increased wear. Monitoring this parameter is especially important for performance driving and in hot climates.
Ambient Air Temperature
Description: The air temperature surrounding the vehicle, usually slightly lower than the intake temperature.
Importance: Ambient air temperature affects engine performance and efficiency. The engine control module (ECM) uses this data to adjust fuel and ignition parameters for optimal combustion under different ambient conditions.
Barometric Pressure
Description: The local atmospheric pressure around the vehicle, displayed as an absolute value.
Importance: Barometric pressure changes with altitude and weather conditions. The ECM uses this information to compensate for changes in air density, ensuring proper air-fuel mixture at different altitudes.
Accelerator Pedal Position
Description: The position of the driver’s accelerator pedal. There can be up to three sensors (D, E, F) for redundancy and accuracy.
Importance: This reading reflects driver input and demand for engine power. It’s directly related to throttle position and engine load.
Relative Accelerator Pedal Position
Description: Accelerator pedal position adjusted for the vehicle’s learned behavior over time.
Importance: This value accounts for long-term adjustments the vehicle makes to driving habits. It may differ slightly from the absolute pedal position.
Commanded Throttle Actuator
Description: The throttle position requested by the ECM based on accelerator pedal input.
Importance: This shows the ECM’s intended throttle opening, which may be influenced by factors beyond just the accelerator pedal, such as cruise control or traction control.
Relative Throttle Position
Description: Throttle position relative to the learned closed position.
Importance: Over time, carbon buildup can affect throttle position. Relative throttle position compensates for these changes, providing a more accurate representation of throttle opening relative to its adapted closed state.
Absolute Throttle Position
Description: How “open” the throttle is, from 0% (closed) to 100% (fully open). Vehicles may have multiple throttle position sensors (TPS A/1, TPS B/2, TPS C/3, TPS D/4).
Importance: Throttle position directly controls airflow into the engine, impacting engine power and response.
Control Module Voltage
Description: Input voltage at the Engine Control Module (ECM).
Importance: This reading reflects the voltage supplied to the ECM. It should show battery voltage when the engine is off and alternator voltage when the engine is running. Low voltage can cause various electrical and sensor issues.
Hybrid Battery Pack Remaining Life
Description: Also known as State of Charge (SOC), it indicates the total charge percentage remaining in a hybrid vehicle’s battery pack.
Importance: Crucial for monitoring the health and performance of hybrid and electric vehicles.
Hybrid/EV Vehicle System Status
Description: Reports various parameters for hybrid/EV systems, including charging state (Charge Sustaining Mode or Charge Depletion Mode), battery voltage, and battery current.
Importance: Provides detailed insights into the operation of hybrid and electric vehicle powertrains.
Calculated Engine Load Value
Description: A calculated percentage representing the current engine torque output relative to the maximum available torque.
Importance: Engine load reflects how hard the engine is working. High engine load can indicate stress on the engine, especially under conditions where load should be low (like idle).
Absolute Load Value
Description: A normalized value representing air mass intake per intake stroke as a percentage.
Importance: Similar to calculated engine load but based on air intake, providing another perspective on engine workload.
Driver’s Demand Engine – Percent Torque
Description: The percentage of maximum torque requested by the ECM based on driver input, cruise control, and transmission.
Importance: Reflects the torque the driver is demanding from the engine, before external factors like traction control intervene.
Actual Engine – Percent Torque
Description: Also called Indicated Torque, this is the current percentage of total available engine torque, including brake torque and friction torque.
Importance: Represents the actual torque being produced by the engine, taking into account various factors.
Engine Friction – Percent Torque
Description: The percentage of maximum torque required to overcome engine friction and run the engine at no load.
Importance: Indicates internal engine friction, which can change over time due to wear.
Engine Reference Torque
Description: The factory-set torque rating of the engine, considered 100% for torque-related parameters.
Importance: Provides a baseline for understanding torque percentage readings. Note that this value is static and doesn’t change with engine wear or modifications.
Engine Percent Torque Data
Description: Used when vehicle/environmental conditions cause the reference torque to change, allowing for up to five different maximum torque ratings.
Importance: Reflects dynamic adjustments to maximum engine torque based on conditions like altitude or fuel mapping.
Auxiliary Input/Output
Description: A composite datapoint reporting various statuses like Power Take Off (PTO) status, transmission status (automatic/manual), glow plug status, and recommended transmission gear.
Importance: Provides a collection of miscellaneous vehicle operation statuses, though support can be vehicle-dependent.
Exhaust Gas Temperature (EGT)
Description: Temperature of exhaust gas at various points in the exhaust system (pre-turbo, post-cat, post-DPF, etc.).
Importance: EGT is critical for monitoring exhaust system health, especially for turbocharged and diesel vehicles. Excessively high EGT can damage components like the turbocharger and catalytic converter.
Engine Exhaust Flow Rate
Description: Exhaust flow rate measured upstream of the aftertreatment system.
Importance: Indicates the volume of exhaust gas being produced, useful for diagnosing exhaust system issues and engine efficiency.
Exhaust Pressure
Description: Exhaust pressure, displayed as an absolute value.
Importance: Abnormal exhaust pressure can indicate restrictions in the exhaust system, such as a clogged catalytic converter or muffler.
Manifold Surface Temperature
Description: Temperature of the outer surface of the exhaust manifold.
Importance: Provides another temperature reading related to the exhaust system, useful for identifying potential overheating or exhaust leaks.
Timing Advance for #1 cylinder
Description: The angle of crankshaft rotation before Top Dead Center (BTDC) at which the spark plug for cylinder #1 fires.
Importance: Ignition timing is crucial for engine performance and efficiency. Incorrect timing can lead to reduced power, misfires, and increased emissions.
Engine Run Time
Description: Reports total engine run time, total engine idle time, and total run time with PTO engaged.
Importance: Provides cumulative data on engine operation, useful for tracking engine usage and maintenance intervals.
Run Time Since Engine Start
Description: Run time in seconds since the engine was last started.
Importance: Simple elapsed time since engine start.
Time Run with MIL On
Description: Engine run time since the Check Engine Light (MIL) was activated.
Importance: Tracks how long the engine has been running with an active fault code, useful for assessing the severity and persistence of the issue.
Distance Traveled while MIL is Activated
Description: Distance driven since the Check Engine Light last illuminated.
Importance: Similar to time run with MIL on, but tracks distance instead of time.
Time since Trouble Codes Cleared
Description: Engine run time since trouble codes were last cleared.
Importance: Tracks engine run time since the last code reset, helpful for diagnosing intermittent issues that may reappear after codes are cleared.
Distance Traveled Since Codes Cleared
Description: Distance traveled since engine codes were cleared.
Importance: Similar to time since codes cleared, but tracks distance.
Warm-ups Since Codes Cleared
Description: Number of engine warm-up cycles since codes were last cleared. A warm-up cycle is defined by specific coolant temperature changes.
Importance: Warm-up cycles are relevant to emissions testing and certain diagnostic procedures.
Fuel & Air Data
This category provides readings related to the fuel and air intake systems, essential for engine combustion and efficiency.
Fuel System Status
Description: Indicates whether the vehicle is running in ‘open loop’ or ‘closed loop’ fuel control mode.
Importance: Open loop uses pre-programmed air-fuel ratios, while closed loop uses feedback from oxygen sensors to adjust the mixture. Understanding the fuel system status is crucial for diagnosing fuel-related issues.
Oxygen Sensor Voltage
Description: Voltage output of the oxygen sensors.
Importance: Oxygen sensors are vital for monitoring the air-fuel mixture and ensuring efficient combustion and emissions control. Voltage readings indicate whether the mixture is rich or lean.
Oxygen Sensor Equivalence Ratio
Description: Oxygen sensor equivalence ratio, also known as Lambda.
Importance: Lambda provides a more direct representation of the air-fuel ratio relative to the ideal stoichiometric ratio.
Oxygen Sensor Current
Description: Current flow through the oxygen sensor.
Importance: Similar to voltage, current readings provide information about the air-fuel mixture.
Short Term Fuel Trim
Description: Real-time adjustments to the fuel injection rate based on oxygen sensor feedback.
Importance: Short term fuel trim reflects immediate corrections to the air-fuel mixture. Positive values indicate a lean condition (adding fuel), and negative values indicate a rich condition (reducing fuel).
Long Term Fuel Trim
Description: Learned adjustments to fuel trim over time, representing long-term trends in air-fuel mixture correction.
Importance: Long term fuel trim indicates persistent deviations from the ideal air-fuel ratio. Consistently high positive or negative values can point to underlying issues like vacuum leaks, fuel injector problems, or MAF sensor inaccuracies.
Alt Text: Graph showing long term fuel trim data, illustrating fuel adjustments made by the engine control module over time to maintain optimal air-fuel ratio. This data is crucial for diagnosing fuel system efficiency and potential issues like vacuum leaks or sensor malfunctions.
Commanded Equivalence Ratio
Description: The desired air-fuel ratio requested by the ECM, displayed as a Lambda value.
Importance: Shows the ECM’s target air-fuel ratio, which may differ from the actual ratio measured by oxygen sensors.
Mass Air Flow Rate
Description: The rate of air flowing into the engine intake.
Importance: MAF sensor readings are essential for calculating the correct fuel injection amount. Inaccurate MAF readings can lead to various engine performance and fuel efficiency problems.
Intake Air Temperature
Description: Temperature of the air entering the engine intake.
Importance: Intake air temperature affects air density and engine performance.
Intake Manifold Absolute Pressure
Description: Pressure inside the intake manifold, an absolute pressure value.
Importance: MAP sensor readings are crucial for determining engine load and air intake volume, especially in turbocharged engines.
Fuel Pressure (Gauge)
Description: Fuel pressure value, a gauge pressure reading.
Importance: Proper fuel pressure is essential for correct fuel delivery and engine performance.
Fuel Rail Pressure
Description: Pressure in the fuel rail, a gauge pressure reading.
Importance: Similar to fuel pressure, but specifically measures pressure at the fuel rail, closer to the injectors.
Fuel Rail Pressure (Absolute)
Description: Pressure in the fuel rail, an absolute pressure value.
Importance: Provides an absolute pressure reading for the fuel rail, useful for diagnostics and comparison to gauge pressure readings.
Fuel Rail Pressure (relative to manifold vacuum)
Description: Fuel pressure relative to the intake manifold vacuum.
Importance: This reading provides fuel pressure in relation to manifold pressure, which can be helpful in diagnosing certain fuel system issues under varying engine loads.
Alcohol Fuel %
Description: Ethanol/alcohol content in the fuel, as measured by the ECM.
Importance: Relevant for flex-fuel vehicles, indicating the percentage of alcohol in the fuel mixture.
Fuel Level Input
Description: Percentage of maximum fuel tank capacity.
Importance: Basic fuel level reading from the fuel tank sensor.
Engine Fuel Rate
Description: Near-instantaneous fuel consumption rate.
Importance: Provides real-time fuel consumption data, useful for monitoring fuel efficiency.
Cylinder Fuel Rate
Description: Calculated amount of fuel injected per cylinder per intake stroke.
Importance: Provides detailed fuel injection data at the cylinder level.
Fuel System Percentage Use
Description: Percentage of total fuel usage for each cylinder bank.
Importance: Indicates fuel distribution and usage across different engine banks.
Fuel Injection Timing
Description: The angle of crankshaft rotation before TDC at which fuel injection begins.
Importance: Fuel injection timing is crucial for engine performance and emissions.
Fuel System Control
Description: Reports status information for diesel fuel systems, including fuel pressure control, injection quantity, injection timing, and idle fuel balance control loop status.
Importance: Provides detailed control loop status for various aspects of diesel fuel systems.
Fuel Pressure Control System
Description: Reports commanded and actual fuel rail pressure, and temperature for up to two fuel rails.
Importance: Detailed data on fuel pressure control in common rail fuel systems.
Injection Pressure Control System
Description: Reports commanded and actual injection control pressure for diesel engines with oil-actuated fuel injection systems (HEUI).
Importance: Specific to HEUI diesel injection systems, providing data on injection pressure control.
Boost Pressure Control
Description: Reports commanded and actual boost pressure for turbocharged vehicles.
Importance: Crucial for monitoring turbocharger performance and boost control system operation.
Turbocharger RPM
Description: Measured turbine RPM of the turbocharger(s).
Importance: Indicates turbocharger speed, useful for diagnosing turbo performance issues.
Turbocharger Temperature
Description: Reports compressor inlet and outlet temperatures, and turbine inlet and outlet temperatures for turbocharger(s).
Importance: Turbocharger temperatures are vital for turbo health and performance. Overheating can damage the turbo.
Turbocharger Compressor Inlet Pressure Sensor
Description: Pressure measured at the turbocharger inlet.
Importance: Provides pressure readings at the turbo inlet, useful for diagnosing turbocharger performance and inlet restrictions.
Variable Geometry Turbo (VGT) Control
Description: Reports commanded and actual VGT vane position, and VGT control status.
Importance: For vehicles with VGT turbos, this data monitors the VGT system’s operation and vane position, which is crucial for boost control and engine performance.
Wastegate Control
Description: Reports commanded and actual wastegate position for electronic wastegate systems.
Importance: For turbocharged vehicles with wastegates, this data monitors wastegate operation, which is essential for boost pressure regulation.
Charge Air Cooler Temperature (CACT)
Description: Temperature of the intercooler air charge for turbocharged vehicles.
Importance: Intercooler temperature is critical for cooling the intake air charge and maximizing engine performance and efficiency in turbocharged vehicles.
Emissions Control
This section focuses on parameters related to your vehicle’s emissions control systems, crucial for environmental compliance and identifying potential issues.
Commanded EGR
Description: The desired opening percentage of the Exhaust Gas Recirculation (EGR) valve as requested by the ECM.
Importance: EGR reduces NOx emissions by recirculating exhaust gas back into the intake. Commanded EGR indicates the ECM’s desired EGR valve position.
EGR Error
Description: The percentage difference between commanded and actual EGR valve opening.
Importance: EGR error indicates how accurately the EGR valve is following the ECM’s commands. High error can indicate EGR valve problems.
Commanded Diesel Intake Air Flow Control
Description: Also known as EGR Throttle, it reports commanded and actual positions of the intake air flow throttle plate used in some diesel EGR systems.
Importance: Specific to diesel EGR systems with intake throttles, monitoring throttle position is important for EGR system diagnostics.
Exhaust Gas Recirculation Temperature
Description: Reports EGR temperature values at various points in the EGR system (pre-cooler, post-cooler).
Importance: EGR temperature monitoring is important for EGR system efficiency and diagnosing potential issues.
EVAP System Vapor Pressure
Description: Gauge pressure of the Evaporative Emission Control (EVAP) system.
Importance: EVAP system pressure monitoring is crucial for diagnosing EVAP leaks, which can cause emissions and fuel economy problems.
Absolute Evap System Vapor Pressure
Description: Absolute pressure of the EVAP system.
Importance: Provides an absolute pressure reading for the EVAP system.
Commanded Evaporative Purge
Description: The desired EVAP purge flow rate requested by the ECM.
Importance: Commanded EVAP purge indicates the ECM’s desired purge flow rate for the EVAP system.
Catalyst Temperature
Description: Temperature of the catalytic converter(s).
Importance: Catalyst temperature is crucial for catalytic converter efficiency and preventing overheating damage.
Diesel Aftertreatment Status
Description: Reports various statuses of the Diesel Particulate Filter (DPF) and NOx adsorber systems, including regeneration status, type, and triggers.
Importance: Provides comprehensive information on diesel aftertreatment system operation, crucial for diesel emissions control diagnostics.
Diesel Exhaust Fluid Sensor Data
Description: Reports DEF type, concentration, tank temperature, and tank level.
Importance: For diesel vehicles with Selective Catalytic Reduction (SCR) systems, DEF data is essential for monitoring DEF quality and system operation.
Diesel Particulate Filter (DPF)
Description: Reports DPF inlet pressure, outlet pressure, and differential pressure.
Importance: DPF pressure readings are crucial for monitoring DPF soot load and diagnosing DPF clogging or regeneration issues.
Diesel Particulate Filter (DPF) Temperature
Description: Reports DPF inlet and outlet temperatures.
Importance: DPF temperature monitoring is important for DPF regeneration and preventing overheating.
NOx Sensor
Description: Reports NOx concentration levels from NOx sensors located before and after the NOx adsorber system.
Importance: NOx sensor readings are vital for monitoring NOx emissions and the effectiveness of NOx reduction systems.
NOx Control System
Description: Reports data on the NOx adsorption system, including reagent consumption rates, tank level, and warning indicator time.
Importance: Provides detailed information on NOx control system operation, including reagent usage and warning system status.
NOx Sensor Corrected Data
Description: NOx concentration in PPM with learned adjustments and offsets.
Importance: Provides a corrected NOx reading, accounting for sensor calibration and drift.
NOx NTE Control Area Status
Description: Reports whether the vehicle is operating within or outside the NOx “Not To Exceed” (NTE) control area, and any NTE-related deficiencies.
Importance: Relevant for emissions compliance testing, indicating whether the vehicle is operating within NOx emission limits under NTE conditions.
PM Sensor Bank 1 & 2
Description: Reports particulate matter (PM) sensor status (active, regenerating) and value for each bank.
Importance: PM sensor data provides information on particulate matter levels in the exhaust, relevant for diesel and gasoline particulate filters.
Particulate Matter (PM) Sensor
Description: Soot concentration measured by PM sensors.
Importance: Directly measures soot concentration in the exhaust.
PM NTE Control Area Status
Description: Reports whether the vehicle is operating within or outside the PM “Not To Exceed” (NTE) control area, and any NTE-related deficiencies.
Importance: Similar to NOx NTE status, but for particulate matter emissions.
SCR Inducement System
Description: Reports SCR inducement status and reasons for activation, related to DEF system issues.
Importance: SCR inducement status indicates whether the vehicle is implementing strategies (like torque reduction) due to SCR system problems.
NOx Warning And Inducement System
Description: Reports information on warning/inducement levels for NOx control system issues, including severity levels and historical data.
Importance: Provides detailed information on NOx warning and inducement system operation, including severity levels and historical data on inducement triggers.
Engine Run Time for AECD
Description: Reports total engine run time for each Emissions Increasing Auxiliary Emissions Control Device (AECD) that has been active.
Importance: AECDs are permitted emission control strategies that can temporarily increase emissions under specific conditions. This data tracks AECD activation time.
Conclusion
BlueDriver OBD2 scan tool offers a comprehensive view into your vehicle’s live data, covering a wide range of parameters from engine operation to emissions control. While direct BlueDriver OBD2 reading air conditioner system data might be limited within standard OBD2 protocols, monitoring relevant engine parameters can still provide valuable insights into the overall health and performance of your vehicle, including indirect indicators related to systems like the air conditioner. By understanding and regularly monitoring these data points, you can proactively maintain your vehicle, diagnose potential issues early, and ensure optimal performance and longevity. Remember to consult your vehicle’s service manual and reliable repair resources for accurate diagnosis and repair procedures based on OBD2 readings.
