This post is just a quick heads-up on how to accurately check the transmission temperature on Mercedes 5 speed (722.6).
For those who like to do their own transmission flush, you know that when checking the fluid level, the transmission’s oil needs to be at 80° C. I have read many threats where people have used IR thermometers or just waited 20-30mins for the transmission to warm up.
Well, while checking my transmission level several times after I did the trans flush on my 02 ML, I noticed that the fluid level was never the same. Once too high, then the next day too low, then right at the middle. I checked for leaks but none were found, so I figured I wasn’t doing it right.
Having bought earlier this year the OBD/Diag reader iCarsoft i980 to read the ABS codes, I decided to give it a try and see if it would read the transmission's temperature. It did not at first, until I played with it a little (and thanks to the iCarsoft support team), an update was required for it to read the transmission module.
Below are screenshots of the update of the i980, as well as a walkthrough on how to get to the trans temperature module.
I also posted a video on YouTube:
When I first did the update, I selected BENZ+OBDII, but still wouldn’t read my trans module. Then I realized that when the BENZ+NoOBDII was selected, version v11.30 was available instead of v11.20 from BENZ+OBDII. It then worked, but disabled the OBD function. I am not sure why the BENZ+OBDII does not offer the v11.30.
I bought the i980 for approximately $130 on eBay which I think was a great investment if you want to read specific Mercedes codes without having to go through a Mercedes Star Diag.
It is far from having the capabilities of the Mercedes Star Diag but it does much more than a regular OBD reader. So far, I was able to read and clear ABS/ESP/ASR codes and now access the transmission's module.
I hope this post will help DIYers achieving their 722.6 trans flush.
Thanks for the reply. I couldn't get the i980 to read the transmission module at all. I felt inspiration when I saw your post and video. Maybe mine was defective. I exchanged it for a MBii which accessed the Transmission no problem. My TCU/TCM got wet and became defective. MBii pin pointed the problem.. I got a new module and was able to erase transmission codes no problem.
Im glad to hear that you were able to get it fixed. I was also thinking to get the MBii at some point until I got my i980 to work. Thanks to you we know now that the MBii can pretty much read/erase most of the MB ECU
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