My 99 GC with climate control temp indicator changes as you turn the dial for both sides of the vehicle. The tempurature changes as it should on the drivers side. The passenger side will not heat or cool, fan will not increase in speed. I did the test and it indicates 56 code. After the test both sides were indicating 72 degrees. Any decrease in the tempurature dial for the drivers side resulted in hearing the A/C turn on a little, fan increased in speed, and it started to cool. Going back to 72 and the cab sounded silent. An increase in the dial to warm the vehicle and you could hear the fan increase and warmer air start to come out.

Movement of the passenger dial resulted in the steady fan speed, even though the indicator increased or decreased in temp as the dial was rotated, as if it does when it operated correctly. Just no change in air output volume or tempurature.

Is it still the "door"?

Seems like the ambient air was just being circulated at all times by the pass side.

find out what the code stands for. sounds like you have a controller issue. fan speed operates differently from blend door operation in a physical sense.

56 code indicates "right tempurature door travel too large".

That doesn't seem right in this case due to the fact; the fan speed will not change either on just the passenger side of the vehicle.

One question I have had since doing the CAL: when you hold in the two buttons (AC & RECIRC) three arrows show up, one indicating lower vents, one indicates mid vent, one indicates an upper vent.

I have never seen these arrows except during this CAL.

Is that right?