94 FZJ90 Heat/AC Temp Control

[Ken Bennington]

Please pardon the typo. I have a 1994 FJZ80 Land Cruiser. I need advice on fixing the connection between the temperature slider on the dash and the mixing valve located top center on the firewall. The valve works when I operate it manually after disconnecting the cable. However, moving the slider does not move that cable, and hence, that valve. I assume that there is some sort of servo that is electronically connected to the slider. Could one you good souls direct me to some resource or give me some advice on how to diagnose this issue, please?

 

[Michael Montgomery]

Hi Ken is it the heat option that's not working ?

 

[Ken Bennington]

Hi Ken is it the heat option that's not working ?

Hi. Heat and AC both work but I must manually open (heat) or close (AC) the valve on the firewall. In other words, the HVAC system seems to be working except that I cannot select a temperature once I move the valve.

 

[Michael Montgomery]

Hi. Heat and AC both work but I must manually open (heat) or close (AC) the valve on the firewall. In other words, the HVAC system seems to be working except that I cannot select a temperature once I move the valve.

If that’s the case it seems rare that the controller unit may be faulty?

I’ve never heard of one personally going wrong.