Hi,

I recently found out a new trick (new to me) to find out the exact engine temperature, however I'm starting to question its reliability.

On the A/C press and hold "REST" button for TEN seconds.
The A/C display will suddenly show two numbers, one number on the left side of the display, and the other on the right.
The one on the left, corresponds to some function( 1,2,3,..6 etc,) so by pressing on the Auto button SIX times, it will show the number SIX on the left, and that corresponds to engine temperature.


Now, on a different note, I was wondering if anyone can help me regarding normal engine temperature. (On the regular gauge, not using the REST method).
Usually my gauge when driving around with the A/C on, is slightly below the division between the 80 and 120. (Naturally it looks like 100 °C to me, but I was told that it's actually 90°C).
My vehicle is a S320 1998 and I live in Saudi Arabia where it's pretty hot this time of year. But it's always reading around that level when I'm driving, should I be concerned ?


Thanks

 

Just my opinion, but most all vehicles run at that temperature so I believe that your car is fine.

 

You're fine. The system/engine is designed to run at that temperature. As for the REST button, that is the diagnostic mode that can tell you all sorts of interesting information. Here is a writeup on it: http://www.babcox.com/editorial/ic/ic40142.htm

 

I run a lower thermostat so my temp is just under 80c.