Economical Scanner to Read Tranny Temp

By economical I mean low cost. Want to change my own tranny fluid and probably won't have a second hand to monitor the instrument panel using the jumped ODB2 connector hack.

I don't expect to need to use the tool for deep diagnostics since I don't really do that.

 

What is your price range? I have an Ancel TD700 that came with Toyota software. It did give me the 2 trans temp readings when I changed my fluid.

$140 ANCEL TD700 OBD2 Scanner Fits for Toyota Lexus Scion Engine Car Diagnostic Scan Tool All System Code Reader for Reading/Erasing Code,1996-2021

https://www.amazon.com/ANCEL-TD700-Transmission-Temperature-Diagnostic/dp/B0BLYXVR4K

 

If you've already got one just point an IR thermometer at the pan for a reasonable approximation. If not they're pretty cheap

 

That is at the very upper end of what I consider economical but may be a good candidate. Thanks

 

Thanks but advice from the people I consider reliable say don't do it.
Have you done it that way?

 

FREE, included with truck.

You have a 2022 truck; you can't use a jumper to put the truck into trans fluid check mode. There are no contact pins on the OBD in those positions. Follow the gear shift procedure only.

No need to spend any money - just learn how to do it. A cool day is best and will give adequate time from the "D" lighting steady and when it begins to flash when over temp.

I must say this procedure needs to be practiced and followed with the proper timing to be successful.

 

Nope I've got a scangauge with trans temps

 

unless you pin the thermostat you're at 190 or more. after pinning mine i sit at 120-140 on the highway and 160 stopped

 

So no jumper is required, interesting. I will practice and see how it goes.
One of my concerns is the time it takes from ready temp to get out of the cab, under the truck to loosen the plug. Not as fast as I once was.
Any idea of the time I have?
Another question is the temp guideline the normal operating temp or something less?

You have been very helpful, thanks

 

The factory transmission fluid check mode does two things: It controls the idle speed to the specified value and starts the steady "D" at the low temperature and starts flashing the "D" at the high end of the check fluid level temperature range.

I do not currently have the low temperature and high temperature values for you, but they are low at around 100 degrees, not at operating temperatures, plus and minus some single digits. The idle speed I do not believe I have ever seen mentioned as to what that is.

As for the amount of time you have to get out of the cab and under the vehicle, IIRC it is like minutes. But you will be able to time it yourself when you practice the procedure for several mornings in a row. The colder the ambient temperature the longer the time allowable to check the fluid level. Cold weather is not at a premium this time of year. If your ambient temperature is around 100 degrees you may not be able to perform the fluid level check this time of year - nobody can even the dealers IIUC.

Please read the instructions for checking the fluid level and understand them. I do not presently know where they are on this site, but they have been posted many times. Your first post sounded like you were already familiar with the procedure.

 

The duration between high and low was long enough to get under the truck twice and check levels. The first time I did a level check, it was around 70 degrees ambient, I timed it at 13 minutes between low and high.

 

Great info, thanks
I watched the care care nut on YT, a very reliable source of info and a master Toyota tech. Lot of mechanics watch his channel. I may have found another person to help as to avoid the rush to get under the truck in time.

I went out and tried to put the car in tran temp mode (no jumper) and no mater how many times or how quickly I went between N-D never activated the mode. Tried cold just after starting and again after a 15 minute errand. I must have done 20+ back and forth. Tried with foot on brake and parking brake engaged. Always with engine running.

Am I missing a step or something or maybe the 22 SR5 still needs the jumper or my remote start is in the way

Edited to add: I tried also with the jumper on the connector. Nothing different, still did not enter the diagnostic mode

 

I was not successful in getting into the "AT Fluid Check Mode" the first couple of times I tried either. You must practice this procedure.

A couple of things you must remove from your thoughts:
Driving for 15 minutes will make the fluid temperature way too high to do the test unless you are doing this in Antartica.
The second thought to eradicate is that using a jumper will accomplish anything for your 2022. The physical contacts and wires were removed from the DLC by Toyota since the production date of September 2019 (i.e. model year 2020). Your truck and my 2021 do not have anything to jumper. You can add a jumper, but it will be jumping nothing at all. See the attached DLC3 schematic documenting the removal.

What was your ambient temperature? We do not know where you are located. If in the South this procedure may not be possible until cooler weather returns.

I just tried this on my vehicle where I did successfully get into "AT Fluid Check Mode" on the first try. Yeah, I'm proud of myself - you will be too.

My ambient temp was ~80 degrees with an overnight cooled engine - i.e. never started. Took ~10 minutes to warm up.

A first:
I also paid attention to the engine speed - the "AT Fluid Check Mode" controls the engine to 700RPM (+/-5RPM) during the "valid test temperature range". My RPM was held higher (1000RPM +/- 5RPM) until the engine warmed up a bit and then dropped to the 700RPM and warmed up for a bit longer. Generally, my RPM when starting my engine COLD without trying to be in the "AT Fluid Check Mode" is usually higher than the 1000RPM. My Ultra Gauge plugged into the DLC3 was the source of the RPM measurements.

So, the "AT Fluid Check Mode" is controlling the RPM during the warmup stage and also during the "valid test temperature range". These are two things people miss who do not use the Toyota "AT Fluid Check Mode" and use other devices such as IR meters or other temp measuring devices. Does this really matter much, probably not, but Toyota built it in so I will use it.


Yes, you are probably missing a step, and my bet it is the step in paying attention to the appropriate display and indications. Each time I do this I get better at paying attention.

1)Put the Parking Brake on. Your foot will also be on the Brake Pedel during all times you are out of Park. It will feel better getting under a running vehicle with the parking Brake on. It is not absolutely necessary for the success of this procedure.

2)Start the engine with the Brake Pedel depressed - just as you normally do. Keep your foot on the Brake Pedel until the shift lever is later moved back into Park after the "AT Fluid Check Mode" is successfully entered in step 4.

3)Move the shift lever and pause for a second or more at REVERSE, NEUTRAL, DRIVE, SELECT downshift to 3rd, 2nd, 1st upshift to 2nd, 3rd, 4th, 5th and 6th; each time pausing for a second. Some of these shifts are unnecessary, but there is no harm. What is being accomplished is making sure there is fluid in all the places that normally contain fluid throughout the transmission. Some places may drain into the pan after sitting overnight. This shifting through all the gears is most helpful after major work on the transmission, not during a simple fluid drain and check. From reading other's posts it is clear that not all people perform this step.

4)Move from SELECT to DRIVE and start your alternating between DRIVE and NEUTRAL selection sequence. Pause for about a second between the two; if necessary, decrease this time between shifts. Pay attention to the display that is between the Tachometer and the Speedometer; when the display is no longer correctly saying you are in DRIVE or NEUTRAL you have entered "AT Fluid Check Mode". Move the shifter into PARK and you may remove your foot from the brake. Put the Parking Brake on if you've not already done so!

5)Notice that your gear shift is in PARK, but the meter display says you are in no gear (low temp) or a steady "D" if you are already within the "valid test temperature range". Or a flashing "D" if above the "valid test temperature range", in this case of a flashing "D" you must abandon the procedure until the truck has sufficiently cooled off - try again in the morning. Under normal cool operating ambient temperatures there will be NO gear selection displayed until the temperature has risen to within the "valid test temperature range" and then a steady "D" is displayed.

No "D" below temp range
Steady "D" within the "valid test temperature range"
Flashing "D" above temp range

6) Wait until the "D" is displayed to check the fluid level. It may take 10 minutes plus to warm up to the "valid test temperature range" with the steady "D" displayed. This time depends upon the ambient temperature and the starting temperature of the fluid. Patience.

Practice this until it is second nature. Then you can do your incremental transmission drain and fill.

I would not expect your Remote start to have any effect upon this procedure. What remote start are you using?

Notes:
I have not defined the "valid test temperature range" in the "AT Fluid Check Mode" because using this procedure provided by Toyota you do not have to know the temperatures or cloud our minds with the minutia. Yes, I was once curious as to what those temperatures were but no longer need to know them to do the procedure correctly.

If you get the steady "D" when first entering the "AT Fluid Check Mode" I would wait for another day as there is no telling if you are at the low or high end of the "valid test temperature range". In this case you may not have enough time to get under the vehicle and perform the drain test no matter how old you are.

Toyota may have/use other terms for:
"AT Fluid Check Mode"
"valid test temperature range"
these are my own derived terms.

I hope this is enough to give you some confidence.

 

I could add this as an edit, but it is so important to learning this procedure a separate post is appropriate.


Practicing getting into the "AT Fluid Check Mode" can be done with a hot engine, it will just give you a Flashing "D" every time. Just turn the engine off before starting to drive anywhere, thus removing the vehicle from the "AT Fluid Check Mode".

 

Wow, I feel like a dope today. Thank you for the detailed reply, most appreciated but it still doesn't work for me.
I tried following your detailed description to the letter slowing down my N-D swaps while paying close attention to the instrument cluster, nothing changed. Truck was sitting for an hour in 80F ambient.
Foot on brake, parking brake on, started engine. Went through all the gear selections you stated. Went to N-D sequence slower this time since I was probably going too fast previously. I might have expected the over temp indication of flashing "D" but nothing happens.

Trying to find a video demonstrating the process but most just talk it not show it. I will try again after the truck is closer to ambient of 75F

 

Here is a short video that you can listen to the cadence of the shifting for the appropriate speed:
3rd Gen Toyota Tacoma – No OBD Trans Fluid Temperature Check Mode on 2021


Another possibility:
I do not know for sure as I have no codes, but if you have any codes the procedure may not be possible. Not all codes show with inexpensive code readers. Perhaps your local Auto Part stores have a good scanner they can/will use on your truck.

I have been informed that ADAS alignments/calibrations cannot be performed with any existing codes; perhaps this procedure is the same. Had my windshield replaced with associated alignment/calibration of the camera and the installer found 20-30 hidden codes, I do a lot of fooling around with my vehicle and had no clue they were there.

 

This is why the procedure feels more like someone at Toyota justifying their job.

Level out the truck, Drain, Fill until it comes out of the check drain, close the check drain, turn on truck wait a few minutes check level add more until its trickling out the check drain and you're good to go.

The truck isnt as picky as the procedure might lead to you believe

 

If it matters just was at the dealer for an unrelated issue and they did the things dealer do with no indications but I cannot say there are no pending codes. My simple code reader (actually second one) died so I have no way to know for sure.

 

I went back and looked closer to that scanner and says coverage stops at 2021. Mine is a 2022 which I hear has different wiring on the diag connector

 

All of my Toyota vehicles are older than my 2016. If I get a chance to try the Ancel on a 2022 or newer Toyota, I will report back.