clivebaxter

I have a 2023 GLE450 with 11000KM. So far no problems except this one. On the MBUX display (the right display panel) there's a menu option to show engine stats such as coolant and oil temperature, turbo boost, battery charge etc. all in one graphical combined screen. The coolant temperature always registers very low compared to the dedicated coolant gauge within the service menu on the instrument cluster (left panel). Even after many miles of driving it only reads 60 degrees or so. The dealer seems to have no idea but I thought I read somewhere (can't find it now!) that this was a known problem with the "Hermes"?? unit. Has anyone experienced this or have any idea of the cause and solution? Thanks!

jkaetz

Post a picture. That sounds like it's showing you transmission fluid temp and not engine coolant temp.

jtjbt20x

You are looking at the transmission oil temperature, not the water temperature.

jtjbt20x

And the HERMES module is for communications with the outside world.

smholl

"You are looking at the transmission oil temperature, not the water temperature."
That is correct. Coolant gauge in center of driver display does not indicate a temperature value. Only cold/hot indication.

clivebaxter

Thanks you for pointing out my mistake. The MBUX display was transmission temperature not coolant temp. Thanks to all who pointed this out!