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2015 Toyota Tundra DC SR5 5.7L
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For those of you running the Torque Pro app, especially those running the 2005-2006 1-Gens who want to display ATF temp, here's a conversion routine I found on the interwebs. I haven't tested it yet, but will be doing so in the next few days or so with my brother-in-laws 2005 Toyota Tundra V8.

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* * * Use at your own risk. * * *
You are directly accessing the ECU firmware with these commands, so
messing this up may influence vehicle management! Be careful!
This tutorial assumes that you are very familiar with the Torque Pro app,
its functions, and menus.
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OK... to create a custom display, we need to fill in the following fields in Torque Pro:


OBD2 Mode and PID
Long Name
Short Name
Min Value
Max Value
Scale Factor
Unit Type
Equation

OBD Header


by pulling the appropriate data from the corresponding codes used by the ScanGauge II:


GAUGE
TXD
RXF
RXD
MTH
NAM
NOTES



As we go through the tutorial I will use the following ScanGauge example of the ATF temp codes posted by SG on their website for 2005-2006 Toyotas that use the CANSF protocol:


GAUGE: Transmission Temperature
TXD: 07E021D9
RXF: 032180000000
RXD: 2810
MTH: 00070064FE70
NAM: TFT
NOTES: Degrees F​


OBD2 Mode and PID
This field comes from the TXD of the SGII file. There are 2 flavors, CAN (controller Area Network) and the rest of the older OBD2 protocols. If it is CAN, you want to use all the characters after “07DF” or “07E0”. If it is “07E1”, then Torque will likely not work for this gauge as the ELM327 may need specific instructions to communicate the transmission control module. For all other protocols, you will use all the characters after the “F1”.
Our example: "21D9"

Long Name
Take this value from the GAUGE field.
Our example: "Transmission Temperature"

Short Name
Take this value from the NAM field.
Our Example: "TFT"

Min Value/Max Value Fields
These are really determined by the data you are gathering and can be set up after you have your equation. Torque does a pretty decent job of rescaling gauges if the data oversteps the range. I suggest setting minimum at "0" and maximum at "300".

Scale Factor
Leave this as 1 because we can scale in the equation if we need to.
**SGII may do some prescaling that I'm not aware of, so further testing is in order and possible offset scaling may need to be incorporated into the equation so the data displays correctly in the app.

Unit Type
Take this value for the notes field.
Our example: "Degrees F"

Equation

Now for the most complicated part: the actual equation.

Why an equation?

Well, look at what a vehicle sensor actually does... it simply measures electrical resistance. The structure and materials of the sensor are calibrated such that specific voltages correspond to a specific "real world" reading, i.e. temperature, O2 levels, etc. What the equation does is convert the machine's voltage numbers into 'human-readable' information, i.e. temperature, speed, etc and display it.

First look at the RXD field. Don’t worry about the first 2 characters. If the second 2 characters are “08”, then you have 1 byte of data and you will only need an “E” in your equation. If the second 2 characters are “10”, then you have 2 bytes of data and you will need to start off your equation with ((A*256)+F). Don’t ask why. This isn’t a lesson in hex.
Our example is “10”, so we will be starting the equation with ((A*256)+F)

Now look at the MTH field. It is separated in 3 four-character sections. The first 4 characters (0007 in our example) are the multiplier. These values are in hex so you must convert them to decimal.

Open up the Windows Calculator and makes sure it is set to 'scientific' view. Click the hex button and enter in the first 4 characters. Then click the decimal button. The value displayed is what you want to use in Torque. "7" is the result for this step. Repeat this step for the second 4 characters (0064 in our example) and you will have the divisor, which is "100" in decimal.

The final four are the trickiest. If you have an F, E, D, C, B, A, 9, or 8 as the first character -- as we do in our example -- then you will be subtracting this number. To calculate this, use Windows Calculator again and set it to Hex. Enter the value and click the 'XOR' key and enter “FFFE”. Click “=”, then click the decimal button and you will see what value you have to subtract from the equation.

If it doesn't start with one of the previous characters, then we will be adding this value.

The last four digits for the MTH piece are “FE70" which converts to “400" in decimal and will be subtracted from the equation.

Our example: (7/100)-400

The final thing to pay attention to is the RXF field, which is 032180000000 in our example. Pay close attention to the fifth character place, i.e. 0321->8-0000000. If you see a "4" here, then your data must be divided by 100. If you see an "8", then your data must be divided by 10. If it is 0, then disregard this equation entry.
Our example: 10

Completed equation: ((((A*256)+F)*(7/100)-400)/10)

OBD Header
Leave this field blank.

This is only a guide and not a bible. If Torque won't display data for a PID it can mean two things: you entered it wrong or your car doesn’t support it. Just because the ECU monitors a sensor does NOT mean the vehicle will support the PID to get that data.

If the "E" and "F" don't return results, then try the letters "A" and "B" in their place.

Note there are two ATF temperature sensors on our trucks... one in the pan/return and one in the torque converter. Both are technically available. I'll see if it is as simple as adding another PID with the letters changed, i.e. an "E/F" equation and a "A/B" equation.

Good luck. Please post up your results.
 

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Thanks for posting this up - how happy are you with the product?
 

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Does anyone know if this will work for the 2006 Sequoia?

I found the code ((((E*256)+F)*(7/100)–400)/10) and ((((G*256)+H)*(7/100)–400)/10). They both read 51.4 degrees this morning when outside was 39 degrees. How can I know if the readings I am getting are correct?
 
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