Porsche 928 Electrics

Electrical information & supplies for late model 928s

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Updated LED/Interior Lights:

The stock interior lights made by Hella are of questionable quality. They originally saw service on a VW and have some long term reliability issues... They become slightly yellowed & brittle with age and tend to just fall apart - they can easily short to the chassis when they do break. The switch function is also too firm for my liking and is unlabelled and the interior trim tends to separate from the edges of the lights which have a very small overlap area to cover this (mine did).

My solution is a replacement lamp holder with equivalent functions but improved ergonomics

VW later model interior light units & simple adaptation for the Porsche harness connections

These later VW versions (Passat, Golf etc) are available in different colors, are totally enclosed, have a bigger frontal overlap to cover trim issues - fit the same sized holes and have the same switch functions with clear labeling - although the lens switches (easily!) long-ways instead.

There is a connection & wiring adaptation needed - see the picture - but I found this very easy to do. The rear hatch light has a more limited space around the opening and that required a slightly different adaptation - but the same lamp holder can fit there too.

These VW units take a smaller 36mm festoon bulb compared to the 42-44mm stock units.

I considered sourcing 36mm LED bulbs for these holders - but these shorter bulbs come with fewer LED elements than 44mm LED bulbs. Since I had already converted my stock units to bright white LEDs (and these seemed only marginally bright enough to me) - I decided to convert the VW fixtures so I could reuse these LEDs. I disassembled the housings and modified the positive bulb holder contact to work with 44mm bulbs, a quite easy change.


They fit perfectly and are nicer to operate and are cosmetically more pleasing than stock

Copyright (c): Alan Moore 2006, 2007, 2008, 2009       Page Updated: 04/03/2009