Club 80-90 Forums

I am dabbling with the idea of fitting a GPS speedo in place of my original. I have found one I like and it fits well (in an old unit, not my own!!)





However when I took my own dash cluster off, I notice there is a circuit board and ribbon cable connections to it on the speedometer. Early vans didn't have this. Does anyone know what the electonics are for? The speedo is analogue and driven by a cable and it is a manual with no cruise control so I cannot understand why there should be any electronics there at all?

The L shaped circuit board strapped around the speedometer head is for the
Dynamic Oil Pressure System (DOPS),
or commonly known as the Buzzer of Doom.
This will have inputs from the charge light, 0.3bar and 0.9 to 1.6bar sensor, ground and rpm signal.

None of the inputs are for the road speed.

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There is a magnetic disc on the speedometer drive on a lot of clusters for water-cooled vehicles (including my basic 1983 van), which provides a speed pulse output.
My van does not have DOPS.

There are a few suppliers of the pulse pick-up, that clips into the speedometer head close to the reluctor ring.
Brickwerks used to sell one by GoWesty (USA).
(I think).

It's for the 2 stage oil pressure "buzzer of doom" system - it has no connection to the speedo operation.