Important
Never touch the glass part of the bulbs with your fingers. Grease from your fingers is vaporised by the heat, coating the reflector and then causing damage.
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Detach the headlamp's round rubber cover.
Unplug the connector from the bulb.
Detach the bulb by pushing it gently upwards and pulling it straight out.
Fit a new bulb in the socket. The bulb's guide pin must be aimed straight upwards.
Press in the connector.
Refit the headlamp's round rubber cover.