That connector goes to the speedo side as the little DOPS circuit board
lives inside the speedo housing for no particular reason.

He sent me photos and he has an 85 cluster.

The rare 84 tach cluster has a smaller foil without any provision for
the future DOPS. The 85 foil has the extra DOPS branch you mentioned but
the connector isn't installed on it and there is an extra resistor
mounted elsewhere on the foil to bypass the missing DOPS. 86+ has the
DOPS connector installed and is missing the bypass resistor, with an
empty spot where it could be.

Mark
a man of many clusters

David Vickery wrote:
> Someone will correct me if I'm wrong, but if you see a 1 1/4" connector pin under the blue foil going into the tachometer side of the cluster as opposed to the blue foil being pinned there, then it is a DOPS, Dual Oil Pressure Sensor, which adds an oil warning buzzer if pressure is too low at 2,000 rpm. That only came on 86+ clusters.
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