Transmission temps, the saga continues, and more questions - with bad answers

with regard to SG reading Transmission Pan and Transmission Torque Converter temps - below is their response to me after I sent them a screen shot of the schematic (no longer posted due to Toyota Corp CAD issued against Ryan) before the schematic post was removed.

From Linear Logic regarding TF2 - Transmission Convert Temperature for the

$160 ScanGauge - SG2 II Ultra Compact 3-in-1 Automotive Computer with Customizable Real-Time Fuel Economy Digital Gauges , Black , 5"

Scangauge II (likely the same for SG III).

Here is the response from their Engineering Team:

"I've compared data we've gathered from a 2019 Tundra and a 2022 Tundra and they use the same parameter ID's as far as I can tell. They both use the same parameter ID for ATF #1, but for ATF #2 the 2022 is missing that parameter ID. I've looked to see if perhaps it was moved to a different parameter ID, but any there were only a handful of parameter ID's the 2022 had that the 2019 didn't have, and based on the data contained with them it's unlikely they were temperature related. Ultimately it appears Toyota, for whatever reason, isn't reporting ATF #2 on the newer Tundra's. I looked around to see if anyone was able to read ATF #2 on 2022+ Tundra's but so far I haven't found anything. It's likely just not reported, and even a dealer level scan tool wouldn't be able to display ATF #2. Why they decided to remove it, I have no idea, but it seems to be pointing towards that. I'll keep looking to see if perhaps it's just been moved to a new parameter ID though."

Hopefully a solution will come once Toyota figures out they have an issue and that even their TechStream software cannot read TF2 - which has been stated here by another member's firsthand experience.

 

Very interesting. And discouraging. And since Toyota service dealers apparently don’t know either (I’m not sure what they do know!) we may never know where or what that dash gauge actually measures. How lame.

 

My 2018 LX570 with the 8 speed also does not have the ATF #2(I think they call it A/T Oil Temp). It has an AFT #3, but the PID is screwed up on both my phone via OBDFusion/OBDLink, as well as the new Launch X431 diagnostic tool I picked up. On both devices ATF #3 will be at -40F when the truck is cold started in my +50F garage. As the transmission temp increases, the temperature does shoot up and eventually will exceed the ATF #1 temperature. When I was pulling a grade with my trailer in tow, I saw a ATF #1 at 242F while ATF #3 was 249F. So it went from -40F up to 249F.

So something was up with the scaling of that PID. Makes you wonder if the 2022+ Tundra also has an ATF #3 and that its also screwed up?

 

UPDATE:

Another few days at the ranch revealed pan temps as high as 215 and the dash gauge, as per usual, bouncing around all over the place. Sometimes it reads high and the pan temps are high(er). Sometimes it reads high and the pan temps are low. I can't figure it out.

I opened a case with the Toyota Brand Engagement people. I told them I had three simple questions I wanted answered:

1. Where is the sending unit/sensor for the dash gauge?
2. If sending unit is someplace other than the pan, what should be the temp variance (in degrees) at that location versus the pan?
3. At what temperatures should I become concerned?

Simple enough right? She said she would first go back to the dealer who had my truck for several days and told me everything was normal, and would report back to me with answers. A few days later, she called back and the dealer couldn't answer any one of those questions. Not one. They simply said they "believed" it to be a gauge issue of some sort, but yet 2 other trucks on the lot did the exact same thing, and there was no verifiably known fix (or problem) for the gauge issue. They had nothing for me. So now it's going up the food chain to a "Field Service Rep" who would consult with Toyota engineering. Unreal. I made it clear that I would not accept the answer that "everything is functioning normally" without my questions being answered. In no world can a factory gauge on the dash of a vehicle spike into the red under unloaded conditions and still be deemed "normal", at least not without a thorough explanation. If that is going to be their final answer, I need to understand how that is logically justified.

Does anyone else miss real mechanics? People who knew how mechanical systems were supposed to work, how to diagnose and rectify problems? Todays "service techs" are nothing more than computer technicians. They can't figure out a dam thing unless the computer tells them what to do.

 

It is possible that 215 is normal. The normal operating temp. for the 10 speed in an F350 is 195 - 215, the 10 speed in a GM 3500 runs a little cooler at 167 - 176. I don't know what the Toyota should run at , but I agree that they should be able to answer your questions. And yes, I miss real mechanics...


Ford:



GM:

 

Not wanting to hijack thread, but new to the Tundra and trying to find out where/how to access the dash gauge for trans temp. I've searched thru the owner's manual without success, and it doesn't even reference the gauge. Is it part of the instrumentation on a non-hybrid 1794?

@SDHNTR--I agree with your assessment and your request for information. Those questions require answers, and information should be readily available.

 

thanks. Yeah it’s unbelievable to me that even the most entry level Toyota mechanic could not answer those questions, much less any other more senior techs.

As for your gauges, you’ll need to toggle through your menu to settings (the gear symbol). Find the “customize right side” and then select “tow gauges”.

 

They don't want you to know. Only one transmission temp output available for Gen3. Disappointing.

 

I question these high temps manuf say that should be normal. We know that manuf are trying to make everything economical as possible and if it means the trans or engine running a bit hotter then so be it. Currently right now I am running my trans with the t-stat pinned open since it's hot as hell. It runs a cool 180-187+/-.

 

Great Questions that I would love to know the answers to. Just Read all 6 pages of comments. installed Scan Gauge II on my 24 SR5, transmission lives at 220 degrees when towing. Live in AZ and tow a camper and a boat. Air temp was 108 on last trip to Flagstaff. coolant stays below 205, eng oil mirrors just below trans temp. SR5 so no bar graph. No warning messages yet. The high temp concerns me. My 2002 trans rarely hit 200. Answer to number #3 from Toyota would be nice.

 

Well Toyota finally closed my case. With zero resolution. The lousy answers to my questions were:

1: the transmission reads temps from“multiple sources” to determine the readout in the gauge.

2: Unable to answer

3: Unable to answer. Even when pressed and a second attempt at an answer was requested, they could not tell me what temp was dangerous.

And lastly, they stated this advanced team read my file again and determinedeverything was normal and operating as designed.

This was all a total waste of time and Iexpressed my extreme dissatisfaction. In what world could it be determined that anunloaded vehicle under mild conditions with a redlined temp gauge is “normal”? I’mbeyond pissed off.

 

How do we get theses PDI’s. I have the fushion pro app with KIWI 3 reader. Thanks.

 

Check the Tuning and Performance section. There is an OBD Fusion PID thread. You might find what you want there or leads to what you want. Or do a search for Fusion PID's.

 

Fusion does not have the enhanced PIDs for Toyota after 2021 yet

 

Thank you. Which app do y’all recommend?

 

I recommend OBDFusion once they get the enhanced PID's. No other apps are going to be any better.

 

I have fushion now.