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It's going to be difficult to determine the fault without known good substitution replacements or a voltmeter and the schematic, which on the CD service manual.
As bizzare as this sounds, jiggle the key in the ignition (but read below about temperatures first). I have found a bad ignition switch to cause no power to get to the CCU (and therefore, blower control).
The blower control unit is basically a box of power transistors that switch various resistances in the "plug" end of the blower motor on and off and is not likely to entirely and completely fail.
Caution: Many of the climate control units LOOK the same but are quite different electrically. For example, the 85 CCU and 86 CCU look alike at first glance, but are electrically different and not interchangeable because the older design would tend to pop transistors if the auxilliary water pump failed. I think it provides +12 to the pump, the newer one switches ground.
There are a lot of interconnected parts here. I don't know where you live but be aware that the fan won't come on at all until a sensor on the engine reaches a minimum temperature. If this wire is missing or the sensor is bad, the fan won't come on, period (and the engine won't run well either).
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