2003 Yamaha 150 wont crank, no tilt/trim

[Justice22]

I have a 2003 Cobia 194 with a Yamaha 150. I left battery one on by mistake for a an unknown amount of time. After noticing this I turned the battery switch off and the following day charged the battery via on board charger. The next day I lowered the motor with the tilt/trim control (with no problem) so I could run the motor a few minutes. When I attempted to crank the motor it only hummed for a moment (like the battery was dead) without engaging the starter. I then turned the battery switch to both batteries assuming that battery one was bad. This engaged the starter for a split second. I tried a second time and nothing. The Yamaha gauges light up but flicker and I can her a clicking on the motor in sync with the flickering of the gauges. Now the tilt/trim will not work at all. If I attempt to turn the ignition to start the engine the gauges go out as if a battery was dead. I checked both batteries and they are fine and have a full charge. All accessories work including the bright deck lights which do not even dim or flicker when attempting to crank the motor. Any help or suggestions would be greatly appreciated.

[Sequoiha]

it sounds like you have a bad or loose battery cable connection going to the engine, you cant look at them and tell, you need to do a voltage drop test on the cables and terminal ends,, probably wouldnt hurt to load test the batteries.. just because they have 12 volts, doesnt mean they have the amperage to do the job..

[Justice22]

Found the Problem

I found the problem. The battery cable inside the conduit from the transom to the motor had corroded and become swollen. Have to replace the battery cable. See attached picture.

[99yam40]

Did it soak in bilge water for a long time?
Looks nasty.

Did the voltage testing show you where the problem was( which cable), it should have if you tested under a load/

[Justice22]

It was nasty! It wasn't in the bilge. It was housed in the grey conduit (pool tubing) that runs from the transom to the motor. Apparantly the conduit held water causing the cables to swell, deform and corrode. And yes, Volatge testing told me where the problem was. I simply tested the cables from batteries to motor. Cables were good up to where they entered the conduit and bad at the exit. I didn't want to remove the cable from the conduit at first since I would need them to feed the new cable through but discovered the cable would not move inside the conduit at all. So, I cut the conduit off and the picture is what I found inside.