I have a standard(?) electric Caterham gauge, says "Caerbont Automotive Ltd" on the back of it.
Block has a pressure transducer sender screwed into the oil gallery with a single wire into the car loom.
Curiously, the gauge has four wires going to three spade connectors on it! One matches color of wire to sender, others are a mystery.
Any ideas? (its not the back-lighting, that's separate and obvious).
Car wiring has had many errors and dead-ends, so maybe these are redundant?
Main question - if needle swings wildly and erratically when running, would you suspect gauge or sender first?