How to get "odometer" readings from OBD-II

I am working on a project that will need the odometer reading of the vehicle, but don't want to use GPS and would rather not use a calculated value. I would like it updated automatically by something like the Torque App (Android). After some reading I see that OBD-II cannot read the odometer. I don't understand why but that's what I've read. Does anyone know of a way to get this reading? Also could anyone expand on the Maintenance Required Light?

Solution1: Take the 'Distance since MIL/CEL/DTC cleared' and add it to a manually entered odometer reading.
Problem: If OBD-II cannot read the odometer how is this calculated?

Solution2: Use the Maintenance Required Light 'mileage' and add it to a manually entered odometer reading.
Problem: How does the MRL keep up with "when to change the oil"?

[edit: ODB-II bus info] http://obdcon.sourceforge.net/2010/06/obd-ii-pids/

 

I'm slightly confused... And I'm not sure if its how you're wording things or if you mean something else.

OBD-II is the onboard computer system in your truck. It is many things. The Odometer is only one piece of data the OBD-II is monitoring on your truck.

The only way you can get information FROM the OBD-II is by having something that plugs into the OBD-II port. For example: I have a Scanguage II that plugs directly into the OBD-II port. It displays a lot of different information that it gets from the OBD-II.

And yes...the OBD-II does get odometer information and SHIT-TONS of other information from the truck in a variety of different ways using sensors & such.

Maintenance Light - Every 4500 miles (since it was last cleared), the light blinks when you startup the truck. If not cleared until 5,000 miles, the light will stay on constant. This is a reminder for you to change the oil.

 

I understand what the OBD-II does and that I need a sensor to read the data (ELM327 Bluetooth + Android Torque App). From what I read (Google Searches) the OBD-II bus does NOT (at least readily) allow you to read the odometer so I am probing other ideas of how to get an ongoing "odometer" reading. It seems that it may not be available (at least readily) because of legal issues of odometer tampering. Does your ScanGuage II read and display the Odometer?

I can readily get the miles from the MIL (Malfunction Indicator Lamp, aka Check Engine Light) and have my project add that to the initial user entered odometer reading, but I would rather not have the user enter the odometer numbers.

So the question remains. How do the MIL and/or Maintenance required light keep track of the distance? What process and values on the OBD-II bus is it using?
Is it just calculating the mileage based off of speed?

 

According to my own searches.... there is a sensor 'Speedometer / Odometer' sensor mounted on the transmission.

This will be reading a 'shaft' within the transmission which will take data - the number of revolutions and/or the speed of that shaft. Ultimately... it takes that data and calculates it into the speed and mileage.

I had a Jeep with a similar sensor. When I put larger tires on, I had to purchase a different speed sensor with a different 'gear' inside that would automatically set the speedo/mileage correctly to the larger tires.

 

Are there any generic or extended Toyota PIDs to read this data directly?

 

Do you know how to access that data? Is there a pid?

 

Apologies for replying to an old thread, but you're looking for your vehicle's Vss. Anyone who has worked in the taxi outfitting business knows and dreads this well. (The meter is dependant upon it) There is one device that directly translates OBD Vss data from the diagnostic socket into simple pulses. It's made by Centrodyne, and it's pretty expensive.

It doesn't work particularly well either, since it tends to interfere with other can bus comms, depending on the vehicle. I'm guessing it has to do with what the particular car's diagnostic port can access.

 

I have a digital odometer that is mostly dead. It can display the last two numbers (example: xxxxxx.21). All other numbers are disrupted in some way.

My question is this...can I just replace the LCD display or even the entire instrument panel and get the actual milage? Additionally, could I get this information from ODB II using the Torque app? Sorry for lighting up a dead thread... Email me any info at derek <at> derfboy <dot> com.

 

Dont know about toyota, work on Fords, we can pull up the odometer when we bring up the data from the instrument cluster. Can you bring up specifically modules(computers) info with toyotas?