That thing is supposed to tell you if your water is low in the battery. If your cells are not covered with enough water and are getting exposed it will make the battery lose its charge quicker.
1998 SVT #95: Toreador Red - SHM headers,K&N Filter, Energy Suspension MM inserts, Cross Drilled Rotors,Redline Tranny Fluid, Custom Billet Aluminum Shift Knob
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