Scan Gauge II - Transmission Temp


American Adventurist
Just entered the below from a thread on the subject from IH8MUD to measure the temp of my 2001 Tacoma 3RZ AT. It works! This should apply for certain model years of Tundra and 4Runners as well.

Following the directions for entering an Xgauge, enter the following codes when prompted...

TXD: 686AF101B4
RXF: 044105B40000
RXD: 2808
MTH: 00090005FFD8
NAME: ATF, tAT, etc. - your choice.

I understand this may not work on 2005 and up Tacoma's. The original thread for your review...


:Wow1: Oooh, oooh, trans temp was the whole reason I bought the scan gauge several years ago. At the time they kept saying check back in a couple months. Can't wait to set it in. I'll do that on the drive down to Death Valley tomorrow!


I don't believe this is the tranny temp code for yotas. Here's a thread on Tundrasolutions that discussed this:

Here's my response on why I don't think it's for the tranny temp. A little background. I installed a fan directly in front of the tranny cooler. So, the fan is pushing air into the cooler.:

I'm using version 3.17.

So after doing some hwy (around 55mph) and city driving, I'm not sure if the codes are for the tranny or something else.

I had the numbers go up to around 156 and was at a stop light. I flipped the switch and the numbers didn't change. I did this multiple times at different temp ranges ( 140's, 160's) and everytime I flipped the switch to the fan, no significant change.

So either my fan is not doing anything to cool the tranny down or maybe that code is for something else.

If it's the fan, maybe it's too close to the tranny cooler. I should try to move the fan away an inch or so and see if that provides any positive results.

If it's the code, could it possibly be the code for the oil temp?

More test as time permits....

The code does provide numbers just not sure for what.
Last edited:


American Adventurist
Reviewing the Tundra Solutions thread it sounds like these folks tried the code on their 2005+ models...

The IH8MUD thread I referenced stated, "A couple people tried on their 05+ tacos and it did not work, someone said the OBDII protocols changed in the 04'/05' revamp."

Driving today I had similar temp changes reflected in my ATF value thay I'd expect in SNG traffic. So, I "want" to be confident for the model years suggested that this code applies to in the original thread could very well be the trans temp. OBTW, I run a Hayden transmission fluid cooler.

Don't micturate in my Wheaties please... although I'm open to other evidence. :D