164L '92: Confounded clicking from cabin heater a/c when it is "off"

["David H. Douglas" <dhdad@domain.elided>]

164L '92: Confounded clicking from cabin heater a/c unit when it is "off"

It clicks at about the speed of a grand father clock. It is from behind the
dash panel, but I can stop it by turning the heater or a/c on. But when the
unit is off: click click click click. 
I became aware of this only in the recent couple of months.

Any ideas. Thanks for your time. Dave. 

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