Ok so I found it
Disconnected it, then reconnected it looked clean did the spades, no rust. dash was showing ---. so I went for a drive because I'm sure I read somewhere it will only show temp once it gets going.
Ten minutes later, still showing ---. Water temp at about 1/4. Let it stand for a couple of minutes to heat up, even the fan came on but still ---.
I'm thinking the sensor is fudged?
