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10

TL;DR The problem you are encountering is the limited resolution of your speed plus fluctuation plus slightly different approaches to calculate power. And finally, you have to think about the term power at wheels. What exactly is power at wheels? I would say, this is the tangential force applied by the wheels onto the street (i.e. the force that's pushing ...


7

Isn't it a standard, so all vehicles are wired the same (for a given connector)? The following information comes from the Handbook of hardware schemes, cables layouts and connectors pinouts website. Here is the SAE J1708 9-pin connector. H,J are not connected. A and B are twisted in cable. C and D are twisted in cable. F and G are twisted in cable. SAE ...


5

I believe you are confusing CAN and OBD. CAN is an electronics interface protocol. Short for Controller Area Network, CAN allows for expandable interconnected systems, so you can add new sensors and actuators to a network with relative ease. It is comparable to SPI and I2C networking protocols. It makes sense that few automotive manufacturers would want to ...


5

Two things to watch out for when using these equations Consistency of units If your mass is in kg, speed in km/h and acceleration in furlongs per week², you're not going to get power in horsepower. Your safest bet is to convert all units to SI metric and convert to hp as a final step. 1000 hp = 746 kW Factor in rotational inertia A rule of thumb is to ...


5

While the fault code that popped the MIL is tremendously useful by itself, freeze frame data offers huge help, as it allows you to see the exact conditions under which the engine decided that there is a fault. You will know at what RPM the code was popped, what the engine load was, whether the engine was warm and in closed loop mode, if it was overheating, ...


4

Start off with a copy of the service manual for your car. The electrical schematics will help you understand where the various annunciators come from. Earlier cars typically have less data available via ODB II (whose original intent was to provide a way to monitor pollution controls). If you add something like a Raspberry Pi to your project you can use the ...


4

Each bluetooth device has a unique 48 bit address and a device name (up to 248 bytes). The name is usually shown when doing a bluetooth scan with a mobile device. The only way you can tell the bluetooth device is an OBD scanner is by checking it's name or address, the fact that it's an OBD scanner does not give it any special properties from the point of ...


4

Cars are manufactured to meet the emission standards of the country it is intended to be sold in. If the car was manufactured in Canada with the intent to be sold in India, it will be designed to meet the emission standards of India. However, if you buy a car in North America and ship it to India, that's a whole other story. Some countries only test the ...


4

Not all DTC's will activate the CEL It is up to the manufacturer whether or not to trigger the Check Engine Light based on the Diagnostic Trouble Code, so a misfire DTC is not the treated with the same severity as an idle-control DTC. In fact, the same make and model manufactured for different markets (Europe vs US) can have sets of triggers, as is the ...


4

It seems like every (lots of people on this forum) one is mixing up what OBD is and what CAN is. OBDII is a standard ratified in 1996 in the US. This standard is required by the government and incorporates 3 things. First is that the vehicle will provide a standard list of data (PIDs). Second is that the vehicle will be able to detect and provide a ...


3

The way to read the codes on your Jeep when they are flashing is, consider them blocked into two digit numbers. You'll get the first digit flashed, short pause, then the second digit. If there is more than one code, there will be a longer break, followed by the next code. Your string of codes break down into: 12. 53, 31, 32, 42, & 55. This website ...


3

According to this response, when the ignition key is removed from the car it's usually not possible to communicate with the car via the OBD port so assuming by "turned off" you mean the ignition key removed, I'd say in most cases it is not possible.


3

HDS HIM stands for Honda Diagnostic System - Honda Interface Module. This is the current HIM. It interfaces with a PC to run scan tool software and is a standalone module reflash unit. It requires a current Honda OEM software subscription to function. The device you reference is not an OEM device. Honda has used at least three interface devices but that ...


3

We find FF so useful that we retain it on the customers invoice in case the same code sets later. It is also very helpful when used in conjunction with a test drive on intermittent faults. It tells exactly how to duplicate the conditions under which the fault set. There are times when its limit of setting on only one code is frustrating because it is not ...


3

They help us home in on what might be the root cause Maybe an example would help explain why freeze frames are so useful Here is the P0300 freeze frame from that infamous Merc GLK280: +-----------------------------------------+-------------+ | Fuel System 1 status | 1 | | Fuel System 2 status | 1 | ...


2

You will not be able to read everything using OBD. Sometimes you can be lucky and the proprietary protocol your car uses can provide you with the right info, however this wouldn't be reliable as it will be considered a diagnostic session by the car's computers (and you may not be able to talk to two computers at once). Instead I suggest you reverse-engineer ...


2

Mode 6 This mode gives the results of self-diagnostics done on systems not subject to constant surveillance. AA Misfire data cylinder 9 The Volvo-a lot those codes are exhaust gas sensors etc Mode 3 This mode shows the stored diagnostic trouble codes. These fault codes are standard for all makes of vehicle and are divided into 4 categories: P0xxx: ...


2

OBD2 style emission testing makes one very large assumption. If every system is working properly then the car is not polluting. This is verified in two ways. If the computer has any hard fault codes in it. Hard fault codes equal something not working. The monitors that test the specific emissions systems have run. If a monitor runs and fails it will ...


2

Actullay the picture above is not a Honda HDS HIM interface, it's a Honda MVCI interface. Honda HDS (Honda & Acura Diagnostic System) is the latest diagnostic software for Honda vehicles. Diagnostic functions available for vehicles of HONDA/ACURA from year 1992 to 2007. Test coverage: Dynamical, Body, Chassis, ABS, SRS, Anti-theft, etc. HDS supports ...


2

The easiest and most accurate thing you can do is buy something like a Racelogic data logger as it's a piece of hardware that's specifically designed for the exact purpose you describe.


2

If a code came up and you cleared it without fixing it, it will come back. Once you clear a code, the computer resets the Readiness monitors and start to conduct a new drive cycle test routine. Since you didn't fix the problem, it will probably fail the drive cycle and light the light again with the same code. Read this post on drive cycles and readiness ...


2

It could also be a one time anomaly. If it were me I would wait to see if it comes back a second time since you already cleared the code. If not, I wouldn't worry about it. If it comes back, time to fix it.


1

Swap the CAN lines and make an adapter harness when you need to connect, I have heard of plenty people doing this to avoid thieves as well as manufacturer warranty voids after tuning.


1

In the UK I obd was only fully compliant by car manufacturers for petrol cars from 2001 and 2004 for diesel cars, so many older cars did not come with an obd port. Your particular car of that year does not have an obd port however it does have a different type of port which you can use to program in the new key. Some auto locksmiths only work on newer cars ...


1

Seems you have some serious overheating issues with your car. Engine goes into limp mode with reduced power. Modern engines do this when there is a serious issue, it allows you to find a safe parking spot. Could be a coolant leak or a broken water pump. The water pump is a service item, how old is your car en when was the pump last changed for a new one? ...


1

To me, you are overthinking this. In general, RS232, CAN and LIN are just the interfaces allowing to transfer bytes between devices, but they do not define how to interpret those bytes. That's where OBD-II, CANopen etc. come into play. Those are standards with quite many specifications, and require lots of knowledge and programming time on both sides. So, ...


1

From a NASIOC thread about the same procedure on an 03 (also same on my 02): The OBDII port is two-piece. First remove the housing by reaching behind, pinching the sides and pushing it towards the floor. Once that part is out, the piece will be dangling by the wiring harness. Now the actual port can removed from the plastic housing by pulling ...


1

To add to @Hari Genti answer. He is exactly correct, CAN is the electrical interface, and OBD-II (On Board Diagnostics version 2) is about the connector and what pins are wired to what. There are a total of 5 different possible electrical interfaces defined for the OBD-II connectors. They are: SAE J1850 PWM (Pulse Width Modulation) SAE J1850 VPW (Variable ...


1

The question doesn't make a lot of sense. All manufacturer specific software work in different ways. They can provide files with raw output but that is not the default thing to do. Normally you read data from the correct bus for the vehicle and then display it in the software or on a handheld device. For more information regarding how OBD works, see here: ...


1

A Toyota Avensis sedan from 2002 is OBD compatible. Cheap bluetooth OBD dongles from amazon do work. It's most easily tested with the various mobile phone apps, they tend to be more user friendly than PC apps


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