As has been said, both front fog lamps are protected by the same fuse, so if the fuse had blown, neither front fog lamp would work, and the Green 'tell-tale' LED in the switch also wouldn't illuminate, as it's supplied from the same circuit header as the fog lamps.

Check where the front fog lamp is plugged-in under the wheelarch -




The chances are that this connection will be OK, the problem is usually with the bulb connector.

The pre-facelift D2 front fog lamps use H1 bulbs.

In most other vehicles, H1 bulbs are connected with a 'Lucar' ¼" spade for the live, with the earth being provided through the bulb's retaining springs and the lamp body, like this -






The D2 uses an unusual H1 connector, which has live and earth in one connector body.

This has a live socket for the ¼" tab to slot into, with the earth provided by edge contacts that press against the base of the bulb, like this -




These can get corroded and make a poor connection.

In the US, you can get replacement connectors (pictured above), here - https://www.belmetric.com/ehalh12-eh...l?cPath=18_557

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