Incorrect Outside Temperature

NathanSA · Mon Mar 07, 2022 9:46 pm

Thanks for checking Stewart.

Likely the way they programmed the FCIM to request the temp from the PCM.
Low priority data request.

NathanSA · Wed Mar 09, 2022 6:18 pm

Found this in the Ranger workshop manual I have.
Will try see if I can align what happens in my vehicle to what is stated here.

This explains why idling around a game reserve in first/2nd gear all day doesn't update the temperature even if the morning start temp is 15 deg and rises to 30 deg by midday!

: IPC_AAT_Detail_Extract.jpeg (275.73 KiB) Viewed 62 times

: IPC_AAT_Detail_Extract.jpeg (275.73 KiB) Viewed 62 times

Wed Mar 09, 2022 6:33 pm

Good find. Shows I should read more.

Bala1 · Wed Mar 09, 2022 6:46 pm

NathanSA wrote: ↑Wed Mar 09, 2022 6:18 pm Found this in the Ranger workshop manual I have.
Will try see if I can align what happens in my vehicle to what is stated here.

This explains why idling around a game reserve in first/2nd gear all day doesn't update the temperature even if the morning start temp is 15 deg and rises to 30 deg by midday!

IPC_AAT_Detail_Extract.jpeg

I have the same temp issue and that info explains it exactly.

We often park in the same place in the morning and go caving for the day. It is generally much hotter when we leave and have noticed the temp not updating for some time.

But when we leave we drive on a dirt road slowly for about 2km then hit sealed road and I generally gradually get up to 100kph as there is no traffic, after a while the temp is correct.

So now I know why.

andrejt · Thu Dec 01, 2022 7:07 pm

NathanSA wrote: ↑Thu Feb 17, 2022 6:53 pm Hi
Reviving an old thread here.

I have the same issue as the OP. Only realised how bad it was when i decided to monitor with Forscan.
The temp display on the IPC and sync unit come from the same source which is the FCIM.
The FCIM gets the temperature from the AAT sensor behind the front bumper on the passenger side.
The PCM also uses this same sensor as an input.
I have confirmed this by using a heat gun and a can of freeze spray.

In forscan you call up a PCM PID called AAT but for the FCIM it's called ExtTemp (on my 2.2).

When i sprayed with the freeze spray both PIDs dropped rapidly but as the PCM value climbed back to ambient temp the value from the FCIM only climbed 2 degrees.

I've also monitored on a drive where both PIDs start at 24 degrees in a cool basement parking.
Outside temp is 35 odd and FCIM value only hits 26 degree after a 20 min drive but the PCM PID value reads 35deg and gets to the value rapidly with driving and airflow across sensor.

The update rate seems quite random as other times it may display the actual outside temperature change.
Initial switch on value is the same between the two modules but only from a dead start i.e. all vehicle electronics have shutdown.
Turning ignition off and then on again has no effect...

I was initially thinking to update the IPC to the latest known indicated on Forscan but realised it's the FCIM that is not updating its value.
I then checked the "Outside temperature source" selection in the as built for the IPC and the two options are FCIM or Aircon control system so essential the same...

Quite annoying as this setup renders the outside air temp display quite useless.

Has anyone solved this with an update to the FCIM?

Hello there,

Can confirm this strange behaviour on my Ford Ranger Wildtrak, year 2020, EU version