ES;

If I understand this correctly, turning ON the wipers (only) blows Fuse No. 1 (the beloved 25A shorty), so my suggestions will be biased toward that. If that fuse blows when wiper switch is not ON, then something else on circuit 1 is amiss.

Refer to wiring diagram at: http://sw-em.com/122S%20Wiring%20Diagram.jpg
...it can be seen that (fat) red wire coming from term 54 of IGN sw supplies power to Fuse 1 (AND by way of the intenal link shown, Fuse 2 - this answers your question why not all terminals have wires...this is absolutely normal!)...and Fuse 1 circuit inturn supplies: Wipers, Fuel Gauge, Oil Pressure Indicator, AMP Indicator, Heater fan, Blinkers.

First, I would classify blowing the fuse after ~3 seconds not as a direct short, but more like an unusually high current, such as might be caused by a locked rotor on wiper motor...wiper mechanism MUST be free and clear to move...a wiper arm(s) jammed, for lack of lube, in the bushing which penetrates the cowl, may very well draw that sort of current...so will any other locking of the mechanism under the dash. I suggest you assure free movement at the arms, then visually of the linkage and wiring to motor parkswitch assy under dash. Hardware like the one on rubber motor mounts have been known to vibrate loose, resulting in jammed linkage as the motor hangs by less than the normal 3 bolts...

If a check of mechanism reveals no obvious issues, entire wiper mechanism probably needs to be removed for internal inspection of motor......an internal motor wire having become dislodged an touching the housing might also cause these symptoms...removing assembly is not too difficult and it sure beats working on your back under the dash! Past assuring a free mechanism, there's little else which can be done with it installed anyway. Removal instructions can be found here: http://sw-em.com/Windshield%20Wiper%20Systems.htm#Review_of_Function_and_Failures

Let us know what you find.
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