Your model, like mine, is loaded with relays. Pull them one at a time and notice the response. In particular, take note of the PCM power relay, and the four SSP (sytem switching power) relays. You can find their location by reading the glove box manual. (While you have the relays pulled ... take the chance to lubricate the bases.)
Other than relays, you may have a chaffed harness. You'll have to remove the windschield cowling to look it over properly.
Good luck!