Nothing happens when I turn the key

[beachskier]

I just recently bought a 1988 Supra Mariah with a PCM 351 in it. I got it for a steal. However when I go to start it I get nothing no clicking or anything. Also none of the gauges are working and none of the devices are working (ie blower, blidge, light etc) I have tested the battery and it is good and is fully charged. I have jumped the connection at the starter relay and it turns over but does not start. I have even attempted to to bypass the nuetral safety switch with no luck. I even pulled the panel out and jumped the lines for the key switch with no response. I am not sure what else to try. The battery cables to the starter relay and ground to the block from the battery are new and in good condition. I am not sure what else to try except for replacing parts but I am not sure what parts maybe bad at this point. I would really appreciate any advice you can give me. Thanks

[themacguru]

sounds like the ground for the boat itself is off.
The motor is grounded what about the rest of the electronics.
Usually in every circuit that is motor related, the engine is the ground and it is attached to the frame and that creates a complete circuit for the rest of the electronics.
Because they are attached to the frame ground.

Look for a fusible link or a ground strop coming from the battery area.
There will be more then just a engine ground.

[69nova454]

There is a breaker by my ign switch on my saltare ,I hit it by mistake and it shut everything down ,looks like my bilge switch

[michael hunter]

Check the main breaker on top of the engine in the rear under the plastic cover. It is a red button.

[chautauquasun]

Another thing to check if the reset button doesnt work...is the start selenoid. I put in a new selenoid and starter and tried to bypass the fender selenoid and wired it wrong (not easy to do...it is a very simple part and wiring is easy but....) With it wired wrong it created the same issue you are having...it had no power at all to the boat even gauges didnt work.

Check you wiring to the selenoid and starter. Did you install a new starter that has the selenoid on starter? I found that you can't bypass the fender selenoid...or at least you couldn't the way I wired it.