Climate control, out of control

[Delboy52]

Was driving along in this hot weather today so had the blower on and set to cold

[GreaseMonkey]

Might be worth checking the Cabin Temperature Sensor (as have had similar symptoms in the past on other cars), located near the Speedo/ Instrument Cluster behind the little grille cut outs in the dash trim panel, might have quite a bit of dust on sensor itself causing it to confuse and over compensate the cabin temp.

Or possibly a heater matrix flap servo/ actuator is playing up?

 

if not, just wondering if it has a Diagnostic function, like some of the later Toyota's,(don't quote me on it but from memory, lol!) by holding "Auto" & "Recirc" at the same time with the Ignition in "ON" position?, normal output DTC'S I think from memory are 21 & 24 which are usually solar sensors, so ignore them.

 

or as you say it could be that the climate control unit is knackered.