Hi out there,

                    I have inherited a 2006 ford fusion (1.6 petrol) Great little car and workhorse that has grown on me, but it  has an annoying fault with the outside temparature reading. It was showing 20 degrees when it was only around 14 degrees outside so I suspected the behind the front bumper. They are not expensive, so I changed it and get exactly the same readings - about 4-5 degrees hotter than it is.

Has anyone had the same issue? I was wondering if there is a "service mode" to calibrate it, or a reset procedure - I have disconnected the battery for 30 mins, but no luck . I had considered fitting a small potentiometer in line and trimming it down that way but I am sure this must be a reasonably common fault.

Anyhow I hope somebody out there has solved the issue before..

Kind Regards

 

Steve

12 hours ago, stevo58 said:

Hi out there,

                    I have inherited a 2006 ford fusion (1.6 petrol) Great little car and workhorse that has grown on me, but it  has an annoying fault with the outside temparature reading. It was showing 20 degrees when it was only around 14 degrees outside so I suspected the behind the front bumper. They are not expensive, so I changed it and get exactly the same readings - about 4-5 degrees hotter than it is.

Has anyone had the same issue? I was wondering if there is a "service mode" to calibrate it, or a reset procedure - I have disconnected the battery for 30 mins, but no luck . I had considered fitting a small potentiometer in line and trimming it down that way but I am sure this must be a reasonably common fault.

Anyhow I hope somebody out there has solved the issue before..

Kind Regards

 

Steve

Hi Steve, those temperature sensors are not very accurate, generally a drift of 2-3 degrees is about right.

The wire will pick up residue heat from the engine bay giving a false indication.

If you look at the sensor on your vehicle compared to a new vehicle today, they are light years apart.

Although mine was covered in dust & minor corrosion, it still works fine, but I'm sure the reading is far from correct.

I'd wait till you've experienced very cold freezing weather, give it some time to adjust.

You could buy a digital one, and clip it to the dashboard & compare the two.

Hi Martyn,

                Thanks for your reply, I was thinking along the same lines - but even when the engine is cold its still well out. I am going to try earthing the sensor earth direct to the body to see if it could be an bad earth fault (or corroded connector) somewhere in the line...

Will update with result

Kind Regards

 

Steve