French forum member has trouble with overhead console.......

[Serge PETIT]

Hello Everybody,

A poor French Blazer owner is in trouble with ambient air temperature displayed on the overhead console. Please help him !
My Blazer is a 2000 , 4,3l, 4WD, 4 doors. I have the short overhead console with sunroof which indicate crazy temp.
When in the garage and switch on ignition temp is ok.
To get outside temp it takes around 5 minutes of driving.
After around 20 minutes temp falls down to 20°C and after may go to 3°C when it is 28°C outside!
I have change the ambient air temp sensor. I have made the checking procedure indicated here http://www.s10forum.com/forum/f200/overhead-blazer-console-install-214399/.
No wrong code displayed meaning the electronic unit normally good.

Please could you, please, tell me:
if there are connections in the wiring under the dash or under the hood to check and where?
If I have to change the electronic unit even if I have no error code (rather pricy…..219$ plus freight). A component failing when hot?

Thanks for help and suggestions.