Coolant temp. gauge not working

On the way home from a great day out last Sunday the water temp gauge faltered abit , then dropped to zero. This is TF 2004. Ten months ago just after I bought the car the same thing happened. At that time I replaced the sender and all was well. This time I have replaced the sender (free from Rimmers after complaining about last years replacement ) and still no reading on gauge. Somewhat miffed as I wanted to take her out today. errrgh. Where do I go next? Any ideas? Help?

OK....to check the gauge, remove the wire from the sender and ground it to the engine block,or cylinder head, now turn on the ignition to the on position the gauge should read at the top of the hot scale....if not then you need to first check the the is power to the gauge, check the continuity of the gauge to sender wire, if those check ok, you then either replace or fix the gauge.

I have just experienced a temp gauge failure too, caused by the wire breaking away from the sensor plug. Also the plug itself had begun to break up internally due to the heat in that area and age. Removed the plug pin and soldered a new connection. Gauge working again.:yesnod:

I think I have found the problem. While fiddling further this morning the plug from the loom to the temp gauge sender fell off. I suspect now that the sender was not faulty but the (tiny) wire to the plug had was broken and finally lost all contact, and that the insulation broke away this am. Now the problem will be to fit a new plug. They don't seem to be available as I suppose they are part of the engine wiring loom. Any ideas how to find one with sufficient wire attached to splice into the existing wiring? I am really p*****d off now as I can see this taking some time. Photo to follow I hope.

Photo.

Oops! Just seen your post David. Can you explain in more detail how you "removed the plug pin…....etc" Any further info on this repair would be most welcome. Chris.

COMMANDER wrote: Photo.

:nonod:

Mmmmm. Photo not successful but we know what we are talking about. The wire is broken right where it enters the plug.

Yes that's exactly what mine did. Turn the plug over and look closely at the pin. On one side of the square pin is a spring tab that holds the pin into the plug body.
You can use a fine screwdriver to depress this tab, and the pin will push back out of the plug.
Solder on a new piece of wire and push the pin back in until it clicks into place

I crimped bullet connectors onto the original wire and the end of the new tail.

Be careful the plastic plug internals don't break up, mine did.

David. Is the clip to which you refer down the rhs as you look at this picture. I can just about see what looks like a tiny u shaped bit of shiny wire. Do you push this to the side, which means going down between the jaws of the pin? So far I have not managed to move anything. Chris.

A quick fix is to fit a standard insulated crimp terminal to the wire and plug it on to the sensor,
but it will need a proper insulated terminal at some point.

IIRC these plugs are made by Ford, have a look at https://www.simtekuk.co.uk/ for a replacement.