Merc 50 electrical issue

[mark45053]

I have a 2002 Mercury 50 hp.

I have a 2002 Mercury 50 hp.
I have been having an intermittent electrical problem:
Sometimes the power trim will go up but not down. If I push the trim button on the side of the motor I hear a click. Sometimes it goes neither up or down.
Sometimes I turn the key and the starter is dead.
If I disconnect then reconnect the battery the problem is sometimes solved.
I can't tell if it is a loose connection or if an electrical component is failing?

 

[papyson]

put a meter on the positive le

put a meter on the positive lead on the starter and ground at the motor...you should read about 12.7 vdc before you try to start...see what the meter reads when you try to start...it should drop some but should not go below 10 volts or something like that..then when motor starts it should recover to 12v or so and then slowly recover to the original reading..with a failure the voltage is probably going to die down to zero or close to it..that says you have either a bad battery or a high resistance connection..when that happens move the positive meter lead to the battery post...to the post..not the wire..if it reads low there also you got a bad battery..if it reads high when trying to turn the starter then you have a voltage drop in the wiring..its probably on the positive side but its possible that the ground side has a bad connection..if you dont have a meter or dont know how to use one then clean both the positive post and the negative post..emory cloth both posts and the wires attached...connect back with a good tight connection..look for discoloration where both wires connect to the terminal...any green tint says you have a chrystilized wire...cut it and put a new lug on it after cutting insulation back to where you get to good wire.. fix the starter problem and you fix the trim problem also i think..sound like low voltage on both..