Electrical (A6)Question 77 of 120
Dim headlights that brighten when engine rpm increases most likely indicate:
a.A blown fuse
b.A shorted headlight switch
c.A weak battery or undercharging condition
d.An open ground on one lamp
Explanation
Lights that brighten with rpm suggest the charging system is barely keeping up, so a weak battery or low alternator output is likely. A charging system test measures output under load. A high-resistance connection can also dim lights but usually affects specific circuits.
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