LR
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ElectricalLow severity

Dim or yellow headlamps

Annoying rather than dangerous.

Symptoms

Weak headlamp beam, lights dim when indicators or the heater are used.

Likely cause

Voltage loss through old wiring, the lighting switch and poor earths, plus tired reflectors.

Suggested fixes

Listed roughly in the order most owners try them.

  1. 1

    Fit headlamp relays

    Use the existing switch to trigger relays fed directly from the battery. This puts full voltage at the bulbs.

    Difficulty:
    Moderate DIY
    Cost:
    £ (Under about £50 in parts)
  2. 2

    Clean the earths

    Clean the headlamp earth points back to bare metal and add a dedicated earth wire if needed.

    Difficulty:
    Easy DIY
    Cost:
    £ (Under about £50 in parts)
  3. 3

    Fit new headlamp units

    Replace dull reflectors with H4 halogen units, or road-legal LED units on 12V negative earth vehicles.

    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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