Hopefully i can help..
Do you still get good heat into the car via the heater system?
Do you hear the cooling fan kick in when the temp needle reaches above normal operating temp?
Yes good heat through heater.Cooling fan operates ok.
Have been told that it could be an earth from side of gearbox,.
Hi..there thanks for your reply..
In some cases its possible in what you mention there..but not often..but certainly have it checked out - sometimes with these its usually a throw up of fan relays/wiring/temperature sensor or corrosion in and around these can often cause problems like that..if the engine isnt actually overheating in itself in which they can check for by using a Infared Thermometer at the engine/thermostat housing/cylinderhead to see if the temp guage reading matches the measurements on the thermometer - if the engine in itself isnt overheating and the temp guage is way upto the red - in that case it more than likely going to be electrical in regards XXXXX XXXXX with the fan relays/resisitor block or wiring to it or possible earth as you mentioned before..depending on the engine/version you have - firstly anyway check out the relays which are located on the fan shroud or the left behind a long plastic panel held with the 2 screws..you'll need to shift the front grille - you'll notice the wiring harness coming in underneath then up behind the panel the relays are behind this 2 of them/resistor is right at the bottom..double check these havent suffered with corrosion..the next port of call would be the temp sender/switch on the thermostat housing.could be giving out false reading bringing the temp guage up and allowing the fan to switch..but as above maybe check out those relays.
The spanner light in question on the digital display is a "service interval light" that usually comes on coincides with the mileage when the service interval is reached or passed once reset by using the trip button by pressing and holding it in / switch ignition ON / let it count down for 10secs unitl =0 is seen and that it reset - you will see the next mileage interval.I do hope this helps