Outside Temperature Incorrect - 2012 Focus

[zetecDon]

Originally Posted by kemoe

Thanks for helping out.

Is this Forum for posting and resolving issues and questions or for attacking people who have found problems with their cars?

Request: Unless you can add useful input to this thread please refrain from adding useless text. I am hoping I can get this resolved and make the information available to other Focus owners. As an owner of two Fords and a fourth generation owner of Ford stock, it isn't in my best interest to try to get my car declared a lemon because of an incorrect outside temperature reading.

They have tried to help you but when you just disregard their advice it kind of ticks them off. I can tell you for a fact that these temperature sensors are never really accurate. You can check different thermometers, weather stations, National Weather Board, online temperatures or any of those other means and not all will have the same temperature. I personally have never relied on a thermometer to tell me if it is going to be icy conditions outside or not.

If you have a legitimate problem with your car, then take it to your local dealership and explain your problem to them. Your car is still under warranty and I suggest you use it. To trade in the car and lose over $5,000 on the value by trading it in for something else will only make it worse for you. You will be paying more for another car that also has an inaccurate temperature sensor. So you can see where I am going with this already, saying that you are going to get rid of a car because of a temperature sensor that is only 2-6 degrees off is very petty.

[warneej]

I have never seen a bank marquee temperature reading to be anywhere near accurate.

What a ridiculous thing to complain about.

[Sniper Focus]

^^ Right, I can drive down a city block and all the marquees have a different temps.

[Chick]

Originally Posted by warneej

I have never seen a bank marquee temperature reading to be anywhere near accurate.

What a ridiculous thing to complain about.

^This. My '07 Civic had a temp gauge was never accurate, nor are either one of the Fiestas that are in my family.

[whynotthinkwhynot]

In the past, Ford has changed things due to customer complaints. For example, Ford used to put oil pressure gauges in lots of different vehicles. Customers complained that the oil pressure would drop at idle- especially in the summer with the AC on. Nobody sued back then, but there were plenty of complaints. Ford then put a resistor in the oil gauge circuit, and changed the sender to a switch- now oil pressure remained steady as a rock, until it would drop to nothing at 7 psi about 1 second before the engine locked up.

I hope Ford will get on the ball and fix this horrible issue for you. How can a 21st century digital man such as yourself survive without knowing the exact outside temperature? Maybe we'll get one of those famous Ford fixes. Instead of actual temperature- what if it simply said: Icy Cold, Cold, Sort of Cold, Warm, Hot, Sweaty Stinky Hot, Hot as Death? Then you'd know exactly what you were up against.

You might want to sue your weatherman too. I've noticed that they are off by as much as 5 degrees every day.

[a_2000_se]

Originally Posted by kemoe

........the sensor is mounted in the mirror......

Does the manual say anything about what the accuracy is?

I was curious where the sensor was mounted. If the inside of your car can climb to over 100 degrees F on a winter day in the sun, think what the temperature might do inside your mirror. Same with the source of your reference temps. And then with a moving car vs. stationary temp sources - it may take awhile for ambient air to permeate the mirror assembly.

If you are looking for a meaningful comparison - you'll need a stable and controlled environment and a calibrated reference source. Depending on accuracy, traceable to NIST. How well insulated is your garage?

Comparing it to anything else may be part of the problem - especially if the sun is involved and/or the temperature changes quickly over a short period of time.

How important it is to you and to what expense you want to go to to find the answer is up to you. .... Remove the mirror (keep it electrically connected) and put it in an "Ice Bath" (bag of water and lots of ice). See what it reads after soaking for say 30-60 minutes. You know ice is frozen at 32 degrees F. - That becomes 'one' point for your graph/experiment.

Do this when the ambient temp is above freezing so you don't end up with a "Popsicled Mirror" (the other point on your graph deals with another known scientific point - "boiling water", 212 degrees F. But I don't recommend this or absolute zero either).

[UnbridledCarnage]

are you factoring in wind chill?

[jetrinka]

Isn't there a warranty for a reason?.....

[viney266]

As a 26 year mechanic ( on bikes ) ...They replace the part with new...inspect the connections. it still works the SAME...let me ask...in my position as a tech ( thats what hipsters like to call us mechanics)...what would you like me to do next???? seriously? tell me...I would love to know.

[kemoe]

Originally Posted by a_2000_se

Does the manual say anything about what the accuracy is?

I was curious where the sensor was mounted. If the inside of your car can climb to over 100 degrees F on a winter day in the sun, think what the temperature might do inside your mirror. Same with the source of your reference temps. And then with a moving car vs. stationary temp sources - it may take awhile for ambient air to permeate the mirror assembly.

If you are looking for a meaningful comparison - you'll need a stable and controlled environment and a calibrated reference source. Depending on accuracy, traceable to NIST. How well insulated is your garage?

Comparing it to anything else may be part of the problem - especially if the sun is involved and/or the temperature changes quickly over a short period of time.

How important it is to you and to what expense you want to go to to find the answer is up to you. .... Remove the mirror (keep it electrically connected) and put it in an "Ice Bath" (bag of water and lots of ice). See what it reads after soaking for say 30-60 minutes. You know ice is frozen at 32 degrees F. - That becomes 'one' point for your graph/experiment.

Do this when the ambient temp is above freezing so you don't end up with a "Popsicled Mirror" (the other point on your graph deals with another known scientific point - "boiling water", 212 degrees F. But I don't recommend this or absolute zero either).

According to Ford, the temp sensor is OK at + or - 3 Degrees F. When checked inside the dealership it is + 2 over. Since it is within specs while sitting in the dealership, there isn't much else to do.

The strange part about this sensor is that it has wild swings of 2 to 8 degrees over. The longer the car has been on, the higher the variation.

The sensor is in the passenger side mirror. The variations are seen during the day or after sunset so the sun does not seem to have much of an impact on the inaccuracy.

Thanks for the reply.