Symptoms
Battery warning light on, flat battery, dim lights.
Likely cause
Failed regulator or diodes, worn brushes, loose belt or a bad connection.
Suggested fixes
Listed roughly in the order most owners try them.
- 1
Test charging voltage
With the engine running, voltage should be around 13.8 to 14.4 V.
- Difficulty:
- Easy DIY
- Cost:
- £ (Under about £50 in parts)
- 2
Replace the alternator
Fit a new or reconditioned unit.
- Difficulty:
- Moderate DIY
- Cost:
- ££ (About £50 to £300)
- 3
Repair wiring and connections
Clean and tighten all connections.
- Difficulty:
- Easy DIY
- Cost:
- £ (Under about £50 in parts)
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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