how do I....
 

change the outside temp read out from celcius to ferinhite? mine reads temps in celcius. I own a 1984 190E

I believe that requires changing the display head.

I have a 1985 380SE. I asked the same question a few weeks ago and it now my understanding that it has to be left on celcius. It did not read in fahrenheit until 1986. Mine is useless as far as I am concerned. I know that 0*C = 32*F and that 32*C is something like 100*F, and 10*C is something like upper 40s to 50*C, but that is about it. As far as me using it as measure the exact temperature while I am driving, it is worthless. Perhaps after time I will get used to it and learn the celsius scale?

I got used to the Celcius reading. 0 means ice danger! And it matches the temperature wheel, also in Celcuis.

cel to feren. goes this way...take celce. temp, bouble it and add 30 degrees you get ferin. temp....with in a degree or two :)

Ok Alex..
When are C and F equal ?????

-40 degrees is the same in F and C

C F
(20.0) (4.0)
(19.5) (3.1)
(19.0) (2.2)
(18.5) (1.3)
(18.0) (0.4)
(17.5) 0.5
(17.0) 1.4
(16.5) 2.3
(16.0) 3.2
(15.5) 4.1
(15.0) 5.0
(14.5) 5.9
(14.0) 6.8
(13.5) 7.7
(13.0) 8.6
(12.5) 9.5
(12.0) 10.4
(11.5) 11.3
(11.0) 12.2
(10.5) 13.1
(10.0) 14.0
(9.5) 14.9
(9.0) 15.8
(8.5) 16.7
(8.0) 17.6
(7.5) 18.5
(7.0) 19.4
(6.5) 20.3
(6.0) 21.2
(5.5) 22.1
(5.0) 23.0
(4.5) 23.9
(4.0) 24.8
(3.5) 25.7
(3.0) 26.6
(2.5) 27.5
(2.0) 28.4
(1.5) 29.3
(1.0) 30.2
(0.5) 31.1
- 32.0
0.5 32.9
1.0 33.8
1.5 34.7
2.0 35.6
2.5 36.5
3.0 37.4
3.5 38.3
4.0 39.2
4.5 40.1
5.0 41.0
5.5 41.9
6.0 42.8
6.5 43.7
7.0 44.6
7.5 45.5
8.0 46.4
8.5 47.3
9.0 48.2
9.5 49.1
10.0 50.0
10.5 50.9
11.0 51.8
11.5 52.7
12.0 53.6
12.5 54.5
13.0 55.4
13.5 56.3
14.0 57.2
14.5 58.1
15.0 59.0
15.5 59.9
16.0 60.8
16.5 61.7
17.0 62.6
17.5 63.5
18.0 64.4
18.5 65.3
19.0 66.2
19.5 67.1
20.0 68.0
20.5 68.9
21.0 69.8
21.5 70.7
22.0 71.6
22.5 72.5
23.0 73.4
23.5 74.3
24.0 75.2
24.5 76.1
25.0 77.0
25.5 77.9
26.0 78.8
26.5 79.7
27.0 80.6
27.5 81.5
28.0 82.4
28.5 83.3
29.0 84.2
29.5 85.1
30.0 86.0
30.5 86.9
31.0 87.8
31.5 88.7
32.0 89.6
32.5 90.5
33.0 91.4
33.5 92.3
34.0 93.2
34.5 94.1
35.0 95.0
35.5 95.9
36.0 96.8
36.5 97.7
37.0 98.6
37.5 99.5
38.0 100.4
38.5 101.3
39.0 102.2
39.5 103.1
40.0 104.0
40.5 104.9
41.0 105.8
41.5 106.7
42.0 107.6
42.5 108.5
43.0 109.4
43.5 110.3
44.0 111.2
44.5 112.1
45.0 113.0

(9/5 * C) + 32

When your tongue freezes to a metal pole. :D

Is your climate control temperature wheel in C or F? If it is in C, you can begin to relate...

Quick, easy, in-your-head conversions for 'human comfort' temperatures

(2 x C) + 30 gives F [double 'C' and add 30]

So, 20C becomes about 70F, etc.

(F - 30) / 2 to go the 'other' way. [take away 30, then cut in half]

Close enough for practical discussions...