If you're still dead in the water, here is some more info; all the relays get their power diectly from the battery, which is about 3 inches away from the fuse box, so thats not hard to chase down. the main computer ground should be mounted to the stupid little grounding plate on the negative battery post, or mounted to the body underneath the battery - remove the battery and it should actually be mounted to the frame the battery sits on... that would be the most likely place for a problem. 2 other grounds to check are below the left headlight (in the engine compartment, don't remove the headlight...) and directly behind the right headlight. BOTH the power and gounds go through connector c100 on their way to the computer. The pcm should be set in the upper right hand side of the firewall. Connector c100 should be between the airbox and left strut tower, its the big white flat one. This connector is the least likly place for a problem, because the power and ground both split so they use 2 pins each in the connector to help distrubute the current.
Your best bets are the relay mentioned by Figols, or the individual grounds at the negative battery post and under the battery itself. Under the batery is quite possibly the worst place I could think of for a ground, because the simple fact I have never seen an 'underneath of a battery' that wasn't corroded to all hell on any vehicle. On some cars its the only place with any corrosion...
If you find the computer is getting the proper supplies and grounds, then you must condemn it as the faulty part.
