The needle in the middle means nothing, unfortunately. The discos have three settings: cold, operating temp, and you're screwed. The middle needle position stays there from about 150 to 230ish and once it starts to move up, it is almost too late. get an ultra gauge and monitor the temps in real time and you'll have a more accurate sense of what's going on.

 

Be sure and realize that the "temp" gauge is not a temp gauge. It will not read hot unless you are melting down. Cheap insurance to get an ultragauge or other OBD2 solution to get real water temps.

Still good advice, that you already took

 

Does the UltraGauge use the internal temp sender that the onboard vehicle computer uses?

 

Yes, the issue is the computer tells the needle to move in ranges base temperatures for each range. Many people believe the top temperature in the normal operating range is too hot and therefor when the needle goes to hot it is too late and you have done damage to the engine. The red warning light does not come on until it is 250 degree F.

 

I have the UltraGauge. So I understand that Discovery 2 owners just leave it hooked up all the time and that way they monitor the engine temp.

I have another question. My horn does not work. I have "hot wired" the horns and they do work. Can not find a wiring diagram. I have exchanged the horn relay with another known good relay and they still did not work. Can I get to the buttons in the steering wheel with out disturbing the driver's air bag?

Another question just for curiosity there is a little motor to the right of the outside mirror control lever. It blows air, what does it cool? Can not find it in the shop manual.

 

The cabin temp sensor is in the little grill by the outside mirror control.

 

You have to remove the airbag. It’s not that difficult, you just have to unplug the battery for ~30 minutes before removal. There are videos on YouTube with step by step instructions. I’ve tried to do it both ways and pulling up the sides to get your hands in, for me it warped the plastic and it doesn’t snap back into shape and can look bad.