S type ambient temperature display

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My ambient temp display has always indicated 10 deg C since I bought the car,  after a a lot of investigation I thought I would pass on a bit of info, If for  any reason the sensing thermistor loses electrical connectivity the computer will default and  indicate 10 deg C  or a very negative reading if it has gone high resistance or again a very high temp 53 deg C if it has gone low resistance   at normal UK temp say 10 deg  C it should be about 60000 ohms , The most likely cause of an inaccurate display is a corroded connector as it is located upfront down on the subframe below the radiator grille  However these sensors ( thermistors ) do fail quite regularly , There are a number advertised on the internet from anywhere from about £15  to £30 but beware they are most likely used items and just as likely to be faulty as your own , I bought a thermistor off eBay ( well actually 5 off them for £ 1.60 )  32 pence each and silicone sealered it inside a small plastic pipe and job done , however you do need to check it has similar temperature / resistance charachteristic as the oem,  part incidentaly it does affect the air con system and also the engine water heating boiler if you have a deisel