Symptoms
Flat battery after standing for a day or two.
Likely cause
Parasitic drain from aftermarket accessories, alarm faults, a sticking relay or failing battery.
Suggested fixes
Listed roughly in the order most owners try them.
- 1
Measure parasitic drain
Use an ammeter and pull fuses to isolate the circuit.
- Difficulty:
- Moderate DIY
- Cost:
- £ (Under about £50 in parts)
- 2
Fit a battery isolator
A master switch prevents drain on vehicles left standing.
- Difficulty:
- Easy DIY
- Cost:
- £ (Under about £50 in parts)
- 3
Replace the battery
Test with a load tester before replacing.
- Difficulty:
- Easy DIY
- Cost:
- ££ (About £50 to £300)
This is general guidance gathered from owner experience and workshop practice, not a substitute for a workshop manual or a qualified mechanic. Costs are rough parts-only guides. Brakes, steering and suspension work affects safety, so if in doubt have it checked professionally.
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