The owner of this 2007 BMW 520D estate, had already had a look at the problem of the rear lamp, which was failing to illuminate and was concerned that the complete rear lamp needed replacing. The light was not operating and as the unit had integral LED lamps, this meant that the whole thing would have needed to be replaced.

He had gone as far as removing the lamp to have a look, but with nothing to see he had put it back in place and driven along to ask me to have a look.

A quick test with a volt meter was all that was needed to confirm that the problem wasn’t the lamp, but the feed to the lamp. Tracing the wiring back, the problem turned out to be a failure in the short wiring loom between the rear hatch and the body.

The loom between the hatch and the body on the BMW is not only well hidden but difficult to get to, but this normally ensures that problems like this don’t occur that often.

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