If the battery is weak, which symptoms might be observed during engine start?

• A. No effect
• B. Higher than normal voltage
• C. Quick start with strong voltage
• D. Slow cranking, low system voltage, or a generator warning

Answer: (D)

A weak battery can’t supply the high current the starter motor needs to turn the engine, so starting is sluggish. That insufficient current also pulls the system voltage down, so you’ll see low voltage across the electrical system and may notice dim lights or slower electrical performance. Because the charging system relies on a healthy battery to regulate voltage, a weak battery often leads to a generator (charging) warning as the alternator struggles to maintain proper voltage. Put together, slow cranking, low system voltage, and a generator warning are the telltale signs of a weak battery during engine start.