You can do that, but if the car has sat overnight, the air temperature works fine. Don't wworry about getting too exact, you would need a resistance value that's 'way off to cause the symptoms you describe.

So 70 F is about 21 C, and you should see about 2.5K ohms across the pins. If you see 5K, then that's a problem, but I wouldn't worry about 3K.

Good luck.

__________________
Chuck Taylor
Falls Church VA
'66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe