Laco

The oat sensor in the HHR and in some other GM cars, will not update the displayed temperature upward, until you have driven 15 minutes at a constant speed of at least 18 MPH or greater. I agree its a stupid design, but thats the way it works, unfortunately. It will update down pretty quickly, but not up!

843de

Thanks Laco, I remembered that "18" was a magic number with the OAT sensor, just was thinking it was 18 minutes of driving time....some days I'm brilliant, and some days I'm brilliantly stupid.

Sno White

I believe the true reason GM does this slow rising temperature display is due to the “ICE POSSIBLE” warning on the DIC.

Liability reasons:
It would be possible in some circumstances for engine heat to affect the temp sensor and the DIC might not display the “ICE POSSIBLE” warning when ice was definitely possible. If the “ICE POSSIBLE” warning went out in a situation like this and there was an accident, whom do you think would be sued?

gguy1

Mine is always slow too it's under front bumper right front behind fog light or black round louver where fog light would go. I'll get to mine one of these days!!

Grizzly old man

Yesterday morning I was chipping the 1/4” of ice off the car, once I could get the door open I decided it would probably be a good idea to start the car so it would be warmed up when the wife and I were ready to go to her doctors appointment.

I really liked the Ice possible warning when I got it going.

Like duh.

Once we got going my wife asked why I had not used the remote start before I even went out to start chipping the ice. I didn't have an answer. I just plain didn't think of it is all.

Sometimes being old sucks, you forget you got all these newfangled gizmos sometimes.

Laco

Maybe, but I have two other non GM vehicles that have OAT's that do not behave that way. They won't increase temp display while stopped, but will soon after you begin moving.

Grizzly old man

Back when I bought my '92 Grand Am it did not have an indoor outdoor thermometer so I bought one of these
http://www.ebay.com/itm/Digital-Indo...item27c3d99418

Even though I junked the Pontiac I still have the thermometer and it still works fine. It updates almost immediately when the temp changes.

Sno White

Haven't read the manual lately, but I believe the ICE POSSIBLE warning is primarily designed to warn a driver the temperature has dropped "during" a driving session. AND to slow down if so warranted.

In our warm cars with short sleeves & shorts one less aware may not notice.

I wonder if GM is aware of the confusion the temperature display causes?

843de

I've always thought that a "Heat Stroke Possible" warning should have been included for HHR's sold in the South and West. Or at least here in Carolina a "Y'all better get some sweet tea before you topple over" warning for those 105° August afternoons.