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27

Ok, before I will answer your specific questions, let's do some introduction on bus systems. It could be that you know parts of these things, but I will start here as people with little or no IT or electronics knowledge should be able to understand this as well. Bus Systems In electronic systems signals are sent from one chip to another using wires (let's ...


16

It is highly probable that the reason your car was reluctant to start was that the time you were running diagnostics had sapped some of the charge from the battery. The battery on the car will not charge unless the engine is running. It is unlikely that this device would harm your vehicle but it is theoretically (and practically) possible to do temporary ...


9

For checking codes, any off the shelf obd2 reader will do. If you want to have fun, ELM327 based OBD2 readers are all the rage right now. You can pick up a bluetooth version for ~$40 on amazon or ebay. Several iOS and android apps (like Torque) exist that can read a signal from these adapters and do full on data-logging. This will let you read/clear ...


9

Everything depends on if the manufacturer multiplexed the windows or not. For example, General Motors tends to multiplex their windows. This means that every door has a module inside it. The module controls the window, door lock, power mirror, etc... and takes inputs from door lock and window switches. The only thing to pass through the door jam is power ...


9

Your glossing over how the hack actually happens. The hack involves erasing the old keys and then reprogramming a new key to the vehicle. If the car uses a smart key then you're in right away. If the car has a physical key then having the correct cut of key is also required. Cars also fall into two categories. The first is the real expensive cars that ...


8

ELM327 is not supported by iPhone as Apples Bluetooth Stack does not support the Bluetooth Serial protocol, the ELM327 is in it's simplest form a ODB to Serial Adapter with the serial data fed to a Bluetooth modem.


8

The PIN code is 6789 (instead of 0000 or 1234).


8

To my knowledge there is no way a scanner can cause issues with your computer electronics. This device is a read only device. It doesn't change anything in your computer. It does, however, communicate with the computer. Through this communication it can give the computer commands, such as to clear the codes. This doesn't write anything to the computer, but ...


8

Looks like the issue is with the incoming signal. Unless your vehicle comes equipped with a flux capacitor, 65 V across battery is a bit too much. Even heavy trucks don't run that voltage to my knowledge. 65535 is the max unsigned 16-bit integer. Looking at the OBD-II wiki page it looks like the formula used by the OBD-II PID as per SAE J1979 is: ( A * ...


8

OBD II is a US government mandated diagnostic interface. This interface is guaranteed to provide a specific set of information including but not limited to engine computer data and engine computer trouble codes. When OBD II was rolled out the US government did not force the manufacturers to also standardize the communication interface to the engine ...


8

On a car with fuel injection there can be two fuel pumps, one high-pressure and one low-pressure. The low-pressure pump moves the gas from the tank up to the high pressure pump. The high pressure pump then raises the pressure to a level that will be useful to the injectors. The two PIDs reflect those two different systems. PID Description Min ...


7

Everything depends on exactly what your looking for. If engine running/not running is sufficient then check the RPM. If RPM is non zero, the engine is running. If the RPM is zero or no communication then the engine is not running. This can be easily done in the OBD stream. If you want anything more than that you need manufacturer specific and then not ...


7

Some motorcycles have a CAN BUS, some don't The OBDII connector type is simply a standard instituted by the SAE (Society of Automotive Engineers). In 1996 the US government mandated that all cars sold in the United States conform to the SAE OBDII standards. They didn't specify motorcycles. As result, a myriad of on-board diagnostic methods were ...


7

The ELM327 is (almost?) as powerful as any other diagnostics solution. That's simply because it only translates the low level OBD protocols to some other format. Bluetooth connections on mobile phones seem to be flaky on many devices. Usually, this shows as established connections suddenly failing during transfer. Restarting the app, and/or turning the phone'...


7

Modern gasoline engines have sensors to measure the amount of air that enters the engine. The ECU then injects fuel to give the correct mixture to get the most efficient burn. A dirty air filter will first show itself by limiting the flow of air at high throttle positions. Rather than causing a rich mixture however, the ECU will see the low air flow and ...


6

It seems that the correct code was already one of the listed ones, still there is a trick: it seems you are able to put the PIN code only one minute after the device was powered.


6

ELM documentation indicates that this is not a query-only problem. I see on page 31 of that document that the issue was that of the rate at which J1850 requests arrive at the OBD system (this is a consequence of the April 2002 update of the J1979 standard). Specifically, they warn you against querying at rates higher than 100 milliseconds (also known as 10 ...


6

since installing new 02 sensor engine light has not reappeared after clearing w/obd2 device and torque free app. TOTAL COST= ~$27 7 31 13 ordered Koolertron F-12 ELM 327 OBDII PC Car Diagnostic Scanner Electronics EggDeal via amazon $9.50 to use w/android smartphone torque free app to read & clear obd codes 8 10 12 friend sprayed hoses he knew to be ...


6

Pending code? The user manual for your device says it should say "PD" for pending codes, so maybe not. "P0130 P" isn't a valid DTC for your vehicle so pending code is really all that makes sense. More specific to your model P0130 is front oxygen sensor circuit range/performance problem (Lean) Possible causes: Open wire to O2 Sensor Short to ground in O2 ...


6

I am not sure of your exact solution, but Brian Blum of Texas Instruments says the amperage draw depends on what state the device is in, of which there are seven states. According to the document in the link, it draws as follows: State 1 (wake-up) - 6.1mA State 2 (pre-processing) - 8.1 mA State 3 (pre-RX) - 12.3 mA State 4 (RX) - 22.3 mA State 5 (Rx-to-Tx) ...


6

Ultimately the answer is yes you can. To qualify this answer, though, you can only control some things, but not all things, then only on some vehicles. You can do simple things through the port, such as turn the A/C pump on, or any other thing which is controlled by the computer (PCM). As an extension, I'm sure you could rev the engine using the same methods ...


6

The federal test procedures for vehicle emission certification(FTP) is run on a dynamometer. It starts with the vehicle at an exact temperature and barometric pressure and humidity. It is run in a lab that has carefully controlled exact air conditions that are maintained throughout the test. The vehicle is kept is stored at the test temperature for hours ...


6

Pin 16 on the ODB-II connector is specified as "Battery Power" or "Battery Positive". There will always be 12v power between pin 4 and 16. Note that pin 5 has "ground" in the description, but that is just for the communication signalling and not for power. The connector will always have power on these two pins regardless of the key position, and when ...


6

Combustion Chemistry from Princeton This isn't much of an answer but here is some data from a Princeton class related to Combustion Chemistry. You will see that the table you are looking for is plotted. Here is the link to the PDF. Manufacturers of Emission Controls Association Here is a study from Manufacturers of Emission Controls Association. ...


6

I think what you're seeing is just an artifact of the way computers work. The number you give is just 65535 with a decimal inserted into it. That is a special number to computers - it's the largest value that can be held in a 16-bit (2 bytes) integer. So, simply put, that is the largest value that can be returned for that particular measurement because of ...


6

The basics are quite simple. The motor generates a certain torque N and a certain power P at a given RPM. Further more, the relation between power and torque is: P = C * N * RPM where C is a constant to convert all that odd units. For N, P in SI units, it is C = pi / 30 Neglecting any losses, Power is conserved from the motor to the wheels so you ...


6

When you say OBD i'm assuming you mean generic data. The answer is outright NO. OBD generic data has no parameters that the alignment can be gleamed from. If the car has a steering wheel angle sensor then maybe you could tell if something is wrong. This data would be available in manufacturer specific. If the angle has been off for a long time at high ...


6

Did you set the protocol for the chip to monitor on? e.g. ATSP5 for KWP-2000 or ATSP0 for "best guess". What about checking the headers as well - ATH1? I use the following string of commands to monitor my full KWP bus, which is obviously different from CAN, but is similar enough that it might be of use: ATI -- check connection from app to scan tool ATH1 --...



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