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5

There is a distinction that needs to be made between: OBD: this is an interface, that specifies the physical and electrical parameters required to connect a diagnostic computer and the car's electronics in a standard way. This is the bit that is mandatory by legal requirement, so that a car manufacturer cannot "lock in" its vehicles by requiring service to ...


4

Depending on the age of your Jeep the recalibration involves either swapping speedo drive gears in the tranny or reprograming the computer. The reasons for having this done are that modern vehicles use many data points for different systems and they all interconnect at some point. ABS, transmission shiftpoints,traction control, cruise control are all looking ...


3

Cause Your car (like most cars) saves the milage in a small memory chip inside the instrument cluster. That chip is called an EEPROM. Like most memory units EEPROMs are subject to wear. If you rewrite the data often enough the chip will fail to save the new data or save corrupted data. This could be the case here. So, why is the "correct" (i.e. new) value ...


3

There are two different types of oil life indicators, as discussed on this page. First, there is the Algorithm-based one: Algorithm-based oil indicators measure lots of factors and then plug the resulting numbers into a formula. Based on the answer to this complex, ongoing math problem, the indicator display will tell you whether the oil is OK, is close ...


3

Your Honda model has a history of failing transmission units. At the least, a once all-over check of the electronics would be advisable and be a bit of insurance against any faults. A Honda OEM/bi-directional compatible scanner would be required to program the transmission. The programming loads an operational 'map' for the system into the transmission ...


2

Yes. That is a significant difference so your speedo will be out by a lot. In some regions it is required by law to have an accurate speedo!


2

I was looking for the similar thing and stumbled on a page which describes the protocol for the 650gs. I haven't managed to try it out yet but it seems promising. http://www.f650gs.crossroadz.com.au/Diagnostics.html Topic is discussed here as well: http://f650.com/forum/showthread.php?25550-Diagnostic-plug-pinout-does-anyone-have-it Plese let my know how ...


2

Great question. I am making an educated guess here, so don't quote me in court;) Because piggyback chips interfere with your car's various inputs I would assume that you are correct and that your MPG score will be inaccurate as a result. I can't say by how much though. These chips usually give an MPG boost of around 10%, so I would imagine your true MPG ...


2

To answer your question ... you should NOT need to reprogram your computer (PCM/ECU) when you replace your transmission as long as it's a stock replacement (or stock rebuild). There is no reason I could find which said this, so I am thinking the person who is talking to you about doing this is trying to get you to spend more money ... on some service he's ...


2

I'm not familiar with the car, but could you not create a temporary cover/box out of some light plastic or aluminium sheet? Either stuck down in the same way as the carpet (although I personally wouldn't bother with carpet at this stage, get the important bits done first and worry about that later...), or screwed to the bulkhead either side of the ECU. I ...


2

Yes in theory it could be done. But getting the mechanical components to work would be difficult and probably result in an awkward and bulky addition to your car. I suspect the end result would be an expensive and unreliable disappointment. It would probably be easier to change the entire gearbox for automatic or a sequential box than try and adapt a ...


2

There is a manufacturer out on the market right now who actually does this. Magneti Marelli has an Automated Manual Transmission or AMT. This was discussed in this thread.


2

I don't think CAN is a necessary part of OBD, it's just the most commonly used system. The OBD requirements are for consistent diagnostics (so that, in theory, any car can be plugged into a standard reader and give a standard set of error codes), wheras CAN is a method for the internal components of the car to communicate (similar in many ways to the USB ...


2

None of this is true. In the same way as there was an EU Directive that all cars be equipped with ABS but TVR didn't subscribe to this. My uncle has just sold a 2005 Caterham Se7en CSR-200 which used MBE management and was definitely not CAN-BUS. We're building another one in October of this year and if it genuinely is CAN-BUS I'll let you know but I have ...


2

OBD is a standard for a diagnostics port that provides emissions-related info on the diagnostics port. Contrary to popular belief its purpose isn't to prevent lock-in by car manufacturers but only to allow service centers a standard way to access emissions-related info required for mandatory checks like the "MOT test" (as they call it in the UK). The ...


2

The two requirements are separate. OBDII is required in all vehicles since 1996. This is primarily an emissions related regulation to formalize how vehicles would relay emissions failures to the user and to mechanics. The standard has many parts, but it primarily designated a connector, its pinout, and allowed one of five different electrical signalling ...


2

How is the OBD and CAN exactly related? Controller Area Network (CAN) is ISO 11898 standard. It, like most other networks, is based off of the OSI model. It specifies certain parameters for communications between vehicle systems. CAN was first specified in 1986 by Robert Bosch at the Society of Automotive Engineers (SAE) congress. CAN uses serial ...


2

For what it's worth, there is a way to access the instantaneous fuel flow rate inside the secret menu on this model. I know this is not exactly what you're after but this parameter has a very fast refresh rate, and to obtain the l/100 km reading it you simply have to divide the value by vehicle speed and adjust for units if needed. With the key in the "off" ...


2

No car has every attribute to be fully autonomous out of the box. Brakes: If a vehicle is equipped with dynamic stability control then software control of the brakes is possible. Dynamic stability control incorporates all the needed pieces to operate the brakes without driver input. The base software will not incorporate software brake control and will ...


1

I recommend my combo, the app Torque Pro for display on a Bluetooth enabled phone or tablet, and a Bluetooth ODBII Reader like my BAFX Elm327 to get the data. Torque Pro has configurable on-screen real-time gauges. The data it can display is only limited by your vehicle's ODBII implementation.


1

Why use a the Canbus to USB adaptor (not a cable!) ? The elm327 comes in at least three flavours: One with an USB connection. One with an bluetooth connection. One with an Wifi connection. I just ordered the third because it uses ancient but widespread IP v4 to set up a connection, making it usuable with almost any computer. (Almost since it might be ...


1

It should be under the dash just to the right of the hood release (based on some internet searching). EDIT: The connector itself should look like this: Most GM vehicles have it just beyond the dash plastic underneath. Since this is a Caddie, it may be under a panel. This video may be of a little help to you.


1

As far as I know, this isn't possible. The EEC-IV has a stored code memory that keeps track of engine problems while it is running but requires you to turn on the diagnostic mode to get those codes. There is also a Key-Off-Engine-Running diagnostic mode that requires you to perform some specific steps while the car is parked and warmed up to diagnose ...


1

Yes, the wheel speed sensors can detect if the vehicle (or at least the specific wheel the sensor is tied to) is moving. On most vehicles you should be able to tie directly into the wheel speed sensor and detect the signal, while not causing any issues with the vehicle itself while in normal operation. The sensor itself is a standard sine wave orientation. ...


1

Your instrument panel is part of the ECU on your vehicle, electrically. If the GEM has been substituted and still the problem has remained, a critical look at the instrument panel is required. Moisture or dampness, even a water entry from the windscreen, could cause corrosion to the IP and cause mis-function. Fords had this problem with European Focus's.


1

The oil indicator is based on an algorithm, monitor(a piece of software). The ECU clock has ticks. When the engine has been operated to a number of ticks(time) the oil light is illuminated. The number of ticks is added to by the average oil temperature and the number of combustion events. Combustion events expose a small amount of oil to degradation by ...


1

I went ahead and pulled out the manual for the car last night. It said something to the effect of the measurement being usage-based (i.e.: things like odometer/number of engine revolutions/etc, which do not directly reflect the quality of the oil, are used instead of an actual testing of the oil itself). It did not specifically say the odometer was used, ...


1

Correct, you do not need to adjust the computer after maintenance/repairs. It might run rough for the first few trips while the computer re-adapts. Also, some cars will show a warning for things like "oil service due" if you do not tell the computer that this has happened.


1

My guess is that your long term fuel trim was commanding the fuel injectors to inject less fuel. When you start your car, you are running open loop (without the feedback of the Oxygen Sensor). In the warm-up phase, if your long term fuel trim is low, the car will stall since it is injecting less fuel than it was calibrated for. When you disconnected the ...



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