car clicks when trying to start then starts

Most Likely Causes

1. 1

   Weak or Dying Battery

   A weak battery provides insufficient voltage to the starter motor, causing the clicking sound. When the car clicks when trying to start then starts, the battery may have just enough charge to eventually turn the engine over. This is the most common cause and typically worsens in cold temperatures.

2. 2

   Corroded or Loose Battery Terminals

   Oxidized or loose battery cable connections create resistance in the electrical circuit. This reduces power delivery to the starter, producing clicking even though the battery has sufficient charge. Corrosion appears as white, blue, or green deposits on the terminal posts.

   Especially common in older vehicles or those in humid climates

3. 3

   Faulty Starter Motor

   A failing starter solenoid or internal starter components may click but fail to engage properly. The clicking occurs as the solenoid attempts to activate, and sometimes succeeds after multiple attempts. This requires professional testing to distinguish from battery issues.

4. 4

   Bad Alternator Not Charging Battery

   If your alternator isn't recharging the battery while driving, the battery charge depletes progressively. You'll notice clicking during cold starts or after the car has sat overnight. The battery voltage drops below the threshold needed for proper starter function.

   Check dashboard warning lights for alternator failure indicators

5. 5

   Defective Ground Cable

   A corroded or broken ground cable prevents proper electrical return paths, reducing starter power. You may see clicking even with a good battery because the circuit can't complete efficiently. Ground cables are often overlooked but critical for starting reliability.

6. 6

   Parasitic Battery Drain

   Interior lights, glove box lights, or faulty modules can drain the battery overnight. By morning, the battery voltage is too low for normal starter function, causing clicks. Once you drive and the alternator charges the battery, subsequent starts work normally.

   Most common after leaving interior lights on or with aftermarket electrical additions

How to Diagnose It

1. 1

   Battery Voltage Test

   Using a multimeter, measure battery voltage with the engine off. A healthy battery reads 12.6 volts. Voltage below 12.2 volts indicates discharge and likely explains the clicking. Perform the test at night or after the car has sat for several hours.

   Tool: Multimeter

2. 2

   Battery Terminal Inspection

   Pop the hood and visually inspect both battery terminals and cable connections. Look for white, blue, or green corrosion deposits, loose clamps, or damaged connectors. Wiggle the terminal posts gently—if they move, the connections need tightening.

3. 3

   Alternator Output Test

   Start the engine and measure battery voltage with the multimeter. With the engine running, a charging alternator should read 13.5–14.7 volts. If the reading stays near 12.6 volts or lower, your alternator isn't charging the battery.

   Tool: Multimeter

4. 4

   Load Test at Auto Parts Store

   Many auto parts retailers offer free battery load testing. A load tester applies electrical resistance to measure how the battery performs under starting conditions. Results show whether the battery can supply adequate current for the starter motor.

   Tool: Battery load tester (shop equipment)

5. 5

   Ground Cable Continuity Test

   Disconnect the negative battery terminal. Use a multimeter set to resistance mode to measure continuity between the cable end and the engine block. Infinite resistance indicates a broken or severed ground cable requiring replacement.

   Tool: Multimeter

How to Fix It

• Clean Battery Terminals

  Disconnect the negative cable first, then the positive cable. Scrub both terminals and cable ends with a wire brush or battery terminal cleaner to remove corrosion. Reconnect positive first, then negative, and ensure connections are tight. This simple fix resolves clicking in many cases.

• Charge or Replace the Battery

  If testing shows low voltage, charge the battery with a trickle charger overnight. If the battery won't hold a charge or is over 5 years old, replacement is recommended. A new battery typically costs $80–$200 and resolves the clicking issue if the battery was the root cause.

• Replace Faulty Alternator

  Shop recommended

  If the alternator isn't charging the battery, it must be replaced. A professional mechanic can perform this in 1–2 hours. Alternators cost $200–$600 depending on vehicle make and model, and installation typically runs $150–$300.

• Replace Defective Ground Cable or Starter

  Shop recommended

  A broken ground cable should be replaced with an OEM or quality replacement. If the starter solenoid is faulty, the entire starter assembly usually needs replacement ($250–$400 parts and labor). Have a shop test the starter before assuming this is the cause.