Hi,
it is a late 96 early 97 japanese Cima, and when the engine has first warmed up the most comfortable temperature on the dial is about 70F on both dials, but after about 1/2 an hour on the motorway that is distinctly chilly and I need to set the dial to almost 80F for driver and passenger dials. I am pretty sure the actual cabin temperature is about the same, but the dial is not seeming reliable. Is it possible I have a grounding issue somewhere? Anyone else notice tha same thing?

From what I can find online, I think the Japanese Cima got a completely different climate control setup that what we got in the US market. For a US market Q45, I would suggest getting the service manual at www.infinitiservicemanual.com and putting the climate control through the self test steps, but I'm not sure how you'd do that on your model. Maybe try whatever steps apply to a 2002 Q45? That's my best guess as to what would be similar. Does yours look like this?



Vs this for the US market:

Hi,

This link shows what the dash looks like, very different to the US one!
https://www.beforward.jp/nissan/cima/bh ... d/2438353/

This one is a bit newer, but shows the dash a bit better:
https://www.beforward.jp/nissan/cima/bh ... _from=2006

I dont have that extra display lower down, that is the slot for the satellite phone link I think.

The main point is that the set point bears no relation to the actual cabin temperature, either the reference voltage for the sensor is drifting or the sensor wire ground is poor or some such issue.

It is repeatable, when the circulating water warms up I need to set the thermostat(s) to about 70F or I am sweating a lot and get a very dry throat. Wheras 10 minutes later I need to set it to about 75F, and another 20 mins after that I am getting a chill unless I set it to about 80F.

it is repeatable day after day. Any ideas?

Those look more like our 2002+ Q45. I'd try looking through the service manuals for them for a self test diagnostic.

Silly me, in the first post I put 96/97, what I should have said was 2006/2007, it was made dec 2006 in Japan.

That explains the confusion! I'd definitely look at the last Q45 service manual we have available and see if there's a self test to run.