Ducato 2.8 JTD

Water Temperature Gauge is very erratic flicking from cold to hot.

Read that disconnecting gauge on dashboard could rectify disconnected and cleaned connection, disconnected battery checked earth all good.

On too sensors one has two spade connections and one two pin connections.

Disconnected sensor with two pin connections fan came on gauge did not move think this one sends signal to Ecu.

Disconnected spade connection sensor and removed from block, this is where the problem comes in, I believe this one has two functions , one for the over temperature light and the other is the resistance for the dashboard gauge.

Reading between spade connection 1 and body is around 29 ohms
Reading between both spades is open connection
Reading between spade connection 2 and body is open

Does anyone know the correct Resistance of this sensor?

Hope this makes sense

Hi Blata

As you say, this is two sensors in one.

One is a switch between one spade terminal and the body (earth) which is normally open circuit, and only goes short circuit in an overheat condition.

The other is a thermistor between the other spade terminal and the body. The information I have found is that the resistance should be about 2000 ohms at 20 degrees C, and will go lower as the temperature increases, in other words it has a Negative Temperature Coefficient (NTC) characteristic.
Sounds like your sensor is faulty/intermittent, so it would be worthwhile renewing it, they aren't outrageously expensive.
Beyond that, a poor connection to the instrument binnacle earth connection has been reported as causing temperature gauge problems.

Sounds like a new sensor for me Thank You it has cleared up a grey area