Towing With Toyota 4Runner

[papasm2]

Hey Ray B,
To get the transmission Temp on your Scan Gague you do need to input a string of codes. I got it from the Scan gauge site. It isn't all that difficult.

[Ray B.]

Thanks all for the replies. It looks like this is all done through the OBDII port and no extra wiring or sensors are needed.

[msweet]

Originally Posted by Ray B.

It looks like this is all done through the OBDII port and no extra wiring or sensors are needed.

Correct. I read somewhere (but can't find it now) that you need the custom code or PID because Toyota doesn't report the transmission temperatures over the OBDII using the industry standard.

[Brian B-P]

Originally Posted by msweet

I read somewhere (but can't find it now) that you need the custom code or PID because Toyota doesn't report the transmission temperatures over the OBDII using the industry standard.

I'd say that there is no industry standard for transmission temperature, rather than that Toyota doesn't follow one.

The On-Board Diagnostics port is required by U.S. (and presumably Canadian) federal law, to support maintenance of emission control systems, so the standard information items are those related to emissions. The OBD-II port exposes the vehicle's communication bus (or one of the buses, using one of five bus protocols over the years, but all include the CAN bus now), so there's lots of information potentially available, but the SAE standard generally defines only a limited set, mostly about the engine.

Each manufactuer has its own standard for the additional data, and may publish it to carrying extents, but if its not published availability of the codes depends on how many customers drive the effort to dig them out. GM and Ford codes are most readily available for vehicle owners using consumer tools. Interesting reading: Non-standard PIDs.