Starting & electrical

Car battery keeps going flat

Repeatedly flat batteries are rarely bad luck. Something is either draining the battery, failing to charge it, or the battery itself is finished.

Symptoms drivers describe

  • Flat every few days, especially after standing
  • Needs a jump start after a weekend
  • Slow cranking that improves after a long drive
  • Battery light appearing occasionally

Possible causes

  • A parasitic drain from a module, light or aftermarket accessory staying awake
  • A failing alternator or charging circuit
  • A battery past its service life or damaged by deep discharge
  • Mostly short journeys never fully recharging the battery
  • Corroded terminals or a poor earth strap

What you can do

  • Note how long the car stands before it goes flat
  • Mention any accessories, trackers or dash cams fitted
  • Avoid repeated jump starts — they can mask the real fault

How we check it in the workshop

We test battery condition and charging output, then measure current draw with the car asleep to find a drain circuit by circuit.

Is it safe to keep driving?

Not dangerous, but you risk being stranded. Worth diagnosing rather than fitting another battery and hoping.

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Want this looked at properly?

Send us your registration and describe the symptoms — we will tell you what the next step is.