PIDS are the serial data that can end up being reached from the vehicle computer making use of a scan device. PIDS include:
- Standing of the OBD II Program Component Screens
(Ready or Comprehensive, or Not really Prepared or Incomplete) - Live Sensor Data
(Air sensor rich/lean indicator, coolant temperatures, MAP value, TPS worth, vehicle rate, mass air flow flow, normal temperature, motor rpm, etc.) - Standing of Buttons or Devices
(get handle on/away. brake pedal switch in/off. TCC engaged/disengaged, etc.) - Lóng and Brief Term Fuel Cut, O2 sensor mix matters, injector length.
- Atmosphere Flow Rate From MAF- The air flow price as tested by the mass air flow sensor.
- Overall Throttle Place- The overall throttle placement (not the comparable or learned) throttle position. Generally above 0% at nonproductive and much less than 100% at full throttle.
- Motor Coolant Heat range- Engine coolant heat range as read through by the engine coolant temp sensor. This worth should become likened to the real coolant temp to find if they fit.
You can make use of an infrared thermometer or various other thermometer to calculate the heat of the cooIant at the thérmostat store. If the real temperatures and displayed temperature do not go with, it would tell you the coolant sensor is certainly not reading correctly. - Engine RPM- The current engine swiftness in cycles per minute (RPM).
- Energy Rail Pressure- Stress in the fuel rail when the reading can be referenced to atmosphere (gauge pressure).
- Ignition Time Advance- Levels of ignition timing (spark) progress for #1 canister (not really including mechanised progress). Intake Manifold
- Stress- Pressure in the intake manifold produced from a Manifold Absolute Pressure (MAP) sensor.
- Brief Term Gasoline Cut (STFT)- The modification factor getting utilized in closed cycle by the PCM to preserve a balanced energy mixture. If the energy system is open cycle, 0% modification should become documented. As with LTFT, the quantity should usually become plus ór minus five. lf better than 10, it shows a gas mixture issue.
- U2 Sensor Result Voltage- The real voltage being created by the air sensor (should become 0.1 to 1.0 volts for a regular zirconia O2 sensor).
For wide-band U2 detectors and linear O2 sensors, the worth may end up being higher, or it may be converted to a zéro to one voIt level.
There may end up being multiple O2 sensor PIDS depending on homw numerous detectors the engien provides (Standard bank1 sensor 1, Loan company2 Sensor 1, etc.). - Period Since Engine Start - Shows the period the engine has happen to be running since it was last began. Vehicle Acceleration - Shows vehicle road velocity as read through by the automobile acceleration sensor (VSS).
- Overall Load Value- This is usually the normalized value of air bulk per intake stroke shown as a pct.
- Complete Throttle Placement- The complete throttle position (not really the essential contraindications or learned) throttle position. Usually above 0% at nonproductive and less than 100% at complete throttle.
- Barometric Stress- Barometric pressure as established by a barometric stress (BARO) sensor. Note some weather conditions services report barometric stress altered to sea level. In these cases, the documented value may not really match the displayed value.
- Switch Temperature- The heat range inside the cataIytic converter.
- Instructed Equivalence Proportion- Fuel techniques that use conventional air sensor displays the commanded open loop equivalence percentage while the program is usually in open up loop. Should review 100% when in shut loop gasoline.
To obtain the actual air/fuel proportion being commanded, multiply the stoichiometric A/Y percentage by the equivalence ratio. For example, gasoline, stoichiometric is certainly 14.64:1 proportion.
If the gas control program was control an equivalence percentage of 0.95, the commanded A/Y percentage to the motor would end up being 14.64. 0.95 = 13.9 A/F. - Commanded Evaporative Clear- This value should go through 0% when no free is instructed and 100% at the maximum commanded clear placement/flow.
- Commanded Throttle Actuator- This worth should end up being 0% when the throttle can be commanded closed and 100% when the throttle is usually commanded open up.
- Control Module Voltage- Energy insight to the handle module. Normally, this should display electric battery voltage minus any voltage drop between the electric battery and the handle component (which should become less than a few tenths of á volt).
Distance Since DTCs Cleared - How many kilometers the automobile has been recently driven since any DTCs had been removed with a scan device. Distance Traveled While MIL On- Tells you how numerous mls the automobile has been recently driven with the MIL lighting on. Also tells you
how very long the drivers has ended up ignoring the light!- EGR Mistake- Calculated error as percent of real commanded EGR. Adverse percent is definitely much less than commanded and positive is even more than instructed. The higher the worth, the even more likely the EGR control device is sticking.
- EVAP Purge- This value is displayed as a percentage and is certainly normalized for all types of EVAP techniques. When EVAP clear is told off, the value should become o%, and 100% when it can be instructed on.
This is an essential worth o check if the motor offers lower than regular LTFT and STFT fuel trim numbers (indicating a wealthy fuel problem). The purge valve may become leaking vapor into the intaké manifold.
Tó get rid of the purge control device as a probable resource of energy vapor, pinch off the purge vapor hose, run the motor and recheck the STFT amount. If it is definitely back to normal, the handbag valve is usually seeping. - EVAP Program Vapor Stress- Evaporative system vapor stress normally obtained from a sensor situated in the energy tank.
- Fuel Degree Input- Signifies the nominal fuel container liquid fill up capacity as a pct of maximum.
- Gas Rail Pressure- Indicates the fuel rail pressure at the motor referenced to atmosphere (gauge stress).
- Gas Rail Pressure Rel Manifold- The fuel rail pressure referenced to the manifold vacuum cleaner (comparable stress).
- Intake Air Temperature- The heat of the air in the intaké manifold as learn by the intake manifold air temperatures sensor. This should become the same as ambient temp in a cool engine that offers not long been started, and should become higher than normal tempertarue if teh motor is cozy and provides been running.
- Minutes Run with Million On- Gathered minutes of engine run period while the MIL light is certainly on.
- O2 Sensor Wide Variety mA- Milliamp present for linear ór wide-ratio air detectors.
- O2 Sensor Wide Variety Sixth is v- Voltage fór linear or widé-ratio oxygen sensors.
- Relative Throttle Position- Relatives or learned throttle place.
- Time Since DTCs Cleared- Accumulated time since DTCs where eliminated with a scan tool.
Warm-ups Sincé DTCs Cleared - Quantity of warm-up process since all DTCs had been eliminated with a scan device. A warm-up is definitely defined as the coolant temperature increasing by at minimum 22°C (40°Y) and the motor temperature reaches at a least 70°C (160°F), or 60°D (140°F) for diesel powered engines.- Energy Program 1 Standing
- Gas Program 2 Position
- Secondary Air Position
- Additional Input Position
- Misfire Keep track of Position
- Energy System Status
- In depth Component Supervising Status
- Prompt Monitoring Standing
- Heated Driver Monitoring Status
- Evaporative System Monitoring Status
- Secondary Air System Monitoring Standing
- A/G System Refrigerant Monitoring Position
- Oxygen Sensor Monitoring Standing
- Oxygen Sensor Heating unit Monitoring Standing
- EGR System Monitoring Standing
- ECU Oxygen Sensor Test Outcomes
DIAGNOSTIC VALUE
PIDS offer valuable analysis information when checking out the operation or status of numerous receptors, circuits and fuses in the vehicle's motor management program.
For instance, if the MIL lamp can be about and you find an oxygen sensor program code, you can call up the air sensor PIDS ón your scan tool screen to observe what the air sensor will be informing thé PCM.
Yóu can also evaluate PIDS to notice how one element may be impacting another.
For illustration, when you all of a sudden open the throttle ón an idling engine, rpm should boost, the TPS reading through should modify and the MAP sensor worth should fall.
PIDS can furthermore be likened making use of a 'graphing muItimeter' or on á scope that changes the voltage values to waveforms.
Evaluating the waveforms of several related sensors can help you discover problems that might otherwise be difficult to detect.
Check out Device PID Capacity
Various scan equipment have various features to screen PlDS.
Thé OEM scan tools used by fresh car sellers are able of exhibiting every possible PID worth that can be constructed into the engine management program.
Most general objective aftermarket scan equipment do not really include the software program that allows them to fit the OEM check out tools in every regard - but for most programs they can screen all the essential PIDS.
The trouble will be you by no means understand what PIDS are missing until you go searching for one and discover it isn't generally there. Bummer.
That's i9000 why several professional technicians own multiple scan equipment: an aftermarket common purpose scan tool, and one or even more OEM scan equipment for the makes they nearly all frequently work ón.
Live data provides real-time dimensions of system advices.
Statuses tell you if a switch, relay or other device is certainly ON/Off of or offers been instructed ON or 0FF.
Openness monitors inform you if the screens have completed or not really.
Test outcomes are assessed by the PCM and likened against preprogrammed pass/fail ideals in teh PCM'h storage.
LIVE Information:
Unfavorable LTFT amounts suggest the PCM can be delivering less gasoline to compensate for a rich fuel condition. If the LTFT is usually higher than 10 either way, it may reveal a problem.
Notice: the heat reading through will depend on the location of the sénsor. If the sénsor is definitely situated under the hóod, it may learn increased than the outdoors temperatrue when the automobile is not really relocating becuase of motor high temperature.
The percentage vlue should end up being 0% when EGR is usually instructed off (at nonproductive), 100% when EGR will be instructed on (typically when traveling under light insert), and between 0% and 100% can be the EGR solenoid is duty cycled on ánd off by thé PCM (based on automobile speed, engine load and heat).
TROUBLE CODES AND Deep freeze FRAME Information
Code readers and scan tools will furthermore screen Stored Diagnostic Difficulty Requirements (DTCs), usually in numeric purchase.
Several scan tools can furthermore screen Pending Problems Codes.
These are usually requirements that show a fault has happen to be recognized, but that the problem has not really yet recurring.
If the problem repeats under equivalent driving circumstances, it will generally cause the Pending Code to become a Stored Code and change on the MIL light.
Severalcheck out equipmentcan also display Freeze Frame data.
These are PIDS that are usually captured when a mistake occurs so you can recommend to them afterwards when diagnosing the problem.
Deep freeze frame information typically includes associated sensor beliefs at the time the fault occurred.
Standing AND Preparedness MONITORS
OBD II requires the sticking with position and openness screens:
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