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Discussion Starter #1
OK,

i no that my battery is dying, but should it effect the readings that i am gettin on my gauges.

when i drive the car at nite, and i turn the headlights on, the temp gauge moves up a bit (like getting hotter) and then when i turn back to my park lights, the temp drops a little bit. (like i am talking 3/4 of a letter on [ NORMAL ]

has anyone had this problem???
 

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Normal and to be expected with a dying battery. The temperature gauge measures changing resistance of sender unit (eg for an ED 39 ohms is hot, 266 ohms is cold and 70 ohms is mid range). Ohm's Law says Voltage (V) = Current (I) X Resistance (R) and accordingly R=V/I. So as you load up your dying battery with the headlights V goes down so R goes down so your temperature guage rises.
 
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