So on my 1982 Diesel Vanagon blue ribbon, I finished repurposing the
yellow glow plug warning light to a red CEL warning light; the red LED
was harvested from another early 80's ribbon. Though Bentley notes LED
bulb polarity at least several times, in each of my blue ribbons, (two
early '80's one 1985) the flat side of the LED bulb housing faces up
toward top of dash. Image of early 80's LED:

https://goo.gl/photos/vFor8SGpMTtyayBu5

On the 1985 ribbon, the bulb is inserted into a black plastic holder.
The bulb legs are slightly different than the earlier type. Though not
shown, these bulbs also have a flat side albeit smaller than the older
style bulb. Bulb orientation (polarity) is shown on the black holder.
Image of 1985 LED bulb holder:

https://goo.gl/photos/1oZftVHC59zs8RYK6

Since my instrument cluster has an, "ahem", different connection
scheme between body harness and cluster, I spent some quality time
staring at the ribbon, using my VOM on a spare similar ribbon, then
confirmed positive and negative paths on the 1982 Diesel ribbon with
VOM and visual. Here's what I found. Image 1982 Diesel blue ribbon:

https://goo.gl/photos/cwva68j1q96DgrpSA

As noted, I used a heat sink to protect the resistor while soldering
on the new switched negative wire from the Jetta ECU. Image of new CEL
wire soldered to 14/12 path:

https://goo.gl/photos/MvCN1pFTzYcKR9DY6

Though the solder joint on the new wire feels secure, I did my best to
sneak in a piece of adhesive type shrink wrap which might, at very
least, keep the wire from straying should the solder joint fail.
(solder didn't really appear to flow 100% on leg of resistor).
Electrical tape may have been a better choice. Image:

https://goo.gl/photos/ZQXtprAo7sdPgh2d6

Neil.

On 8/21/17, Neil N <musomuso@gmail.com> wrote:

> All sorted. Now I'll have an orange CEL light!

--
Neil n

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