89 Mercury 80HP lost power to controls??

Hi all, could use some help here. I have a 1989 80HP Merc that I just picked up. Got it on my boat and everything was working fine, started right up, trim/tilt worked no problem. Shut her down... tried to start her back up again and for no reason, there was no power to the control box. The trim/tilt trigger and ignition switch do nothing.

So, I went back to the motor... checked the battery (fine 12v...switch was on), and ran a jumper from the battery line to the trim up solenoid. worked fine. Ran a jumper from the battery line to the trim down solenoid. Also worked. Ran a jumper from the battery line to the starter and she cranked fine. So, the problem has to be with the controls. Went back to the controls and everything was working normally again. trim/tilt and ignition all worked from the controls.

Next day, went back out to start her up in the driveway and she started fine. let her run a bit then shut her down. Went to start her again and nothing from the controls again. Trim/tilt/ignition doing nothing. Ran the same jumper test as above and everything works fine at the motor. This happened 3 times. Power to the controls seems to come and go??

Does anyone have any experience with this? Not sure if it's a faulty ground, bad power wire or if there's some kind of kill switch on this thing. Could really use some advice. Thanks!

Re: 89 Mercury 80HP lost power to controls??

sounds like a bad ground

go back through all wiring and check again
good luck

Re: 89 Mercury 80HP lost power to controls??

Hey
I have the same motor that had the same problem when I got it. It turned
Out to be the harness that plugs into the motor. The conection was a little loose
And corroded. I just cleaned up the conection and zip tied it together. It worked
Great for a year and then I replaced the cdi harness and never had a ploblem again.
A bad grround also is most likley if that is not the case with the harness.

Well good luck with it. I've had good luck with mine. Lots of grunt!
Cheers

Re: 89 Mercury 80HP lost power to controls??

Thanks guys. I figured out part of the problem. Turns out there is a fuse in the hot wire in the wiring harness on the motor. Once I realized that, I checked it and sure enough, it was blown. So I replaced the fuse and hit the trim down and it worked. When I went to trim it up, fuse blew again. So, for some reason the trim motor is drawing to much power. Anyone have any ideas why that would happen? Thanks.

Re: 89 Mercury 80HP lost power to controls??

So, is it the UP or the DOWN? According to your other thread on the same topic it's the DOWN....