OBDII Protocol for 150 Prados in recent years

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GeeWhizz

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GeeWhizz the STN1110 processes the ELM327 command set so should still be able to use AT AL to see if you start seeing all parts of the multi-frame messages or can you already see them?

Out of interest what software are you using to run your working interface?

The log that I posted above was using a Chinese ELM327 clone to monitor (AT MA) the Prado's OBDII port while I was debugging the problems that I was having with my custom designed interface that utilised an STN1110. (This interface has worked reliably for several years with my previous MT2016 GX.) The STN1110 does not have the 8-byte limitation of the ELM327.

The default configuration of the STN1110 returns all frames of a multiframe response, so the log that I posted above is a bit of a red herring.

There are a couple of major differences between the CAN/OBDII networks in the 2016 and 2023 Prado 150s. The first is the structure of the networks. On the 2016 Prado, the DLC3 jack is connected to a different segment of the CAN network, resulting in far more data being visible using monitoring (Command AT MA). I found that very little data is visible on the DLC3 jack in the 2023 Prado (Not much more than those 45A and 4E0 frames logged above), requiring considerably more commands to be sent. The second difference is that Toyota is in the process of updating its protocols to conform with the UDS standard. This change is what has caused me the most grief over recent months - an area where your knowledge and experience has been invaluable to me. I can report that during my recent 3-day trip towing the caravan, my inteface and display worked perfectly, so the bugs related to reporting torque converter lockup seem to have been eliminated.

I have been developing a custom designed interface using a PIC32MX microcontroller to drive the STN1110 over the last eight years. So, to answer your question, the software is custom designed. The original design was for a 2013 Kluger (using a PIC18) which has a CAN network remarkably similar to the MY2016 Prado. With the DPF problems of the early 2.8L Prado, I started logging and charting DPF data in real-time. This developed into a "black-box" trip recorder, recording transmission temperature, selected gear, speed and RPM data and displaying in real time on a 3.5" LCD touch screen. I have added several other features including video camera switching, allowing the caravan's reversing camera output to be displayed on the Prado's main screen; indicator sound enhancement and a wireless connection.