2018 Suzuki 300 issue

[Matagorda Sportfishing]

Is there someone that can help me with an ongoing issue with one of my 2018 Suzuki 300s. 36 Contender with trip 2018 Suzuki 300s.




Boat went through a complete rewire the beginning of the year. Have ran about 25 offshore charters since the rewire and not a single issue. One day while leaving a location offshore , I got a 8-2 code on my starboard engine along with a message that said (Check Throttle System)




I was unable to shift from neutral to forward with that engine . When engaged the binnacle forward it just flashed in the neutral position on the Suzuki SMG4 gauge. I made it back in with the remaining 2 engines .




Took it to the shop. They replaced the below per the first place I took it :


Shift actuator




Throttle position sensor




All plastic bushings




Wiring harness to that motor




BCM harness




Neutral safety switch







Took it back out after all that and still the same issue ……







Had another mechanic take a look at it . They checked all electrical connections , replaced the push button start/stop pad, replaced the perko switch for that engine , tried a brand new BCM , switched the computer from my center engine to the starboard engine , tried another shift binnacle .




Tried it again today and ran it for 45 minutes without an issue.

Stopped several times and shifted from neutral to forward and to reverse . I did this a lot of times during the 45 minutes.




Thinking it may be fixed , I tied the boat up at the dock and let it idle for a while . All of a sudden, here comes the 8-2 code again on that starboard engine and also the message check throttle system on the gauge . Turned off that perko to that engine for about 10 minutes and then switched it back on . Turned on the key and no code and it shifted fine . Loaded the boat onto the trailer and put the engines in neutral and then again the 8-2 code pops back up .




Does anyone have a clue what the hell is wrong with this damn thing ?

[Solarman]

As sophisticated as these new engines are I suggest you return to that second mechanic (hopefully certified Suzuki mechanic) and explain the situation. Possibly all your info could help solve your situation?
On this site "redlowrey" might be your best help. But each time a mechanic goes through checking out a problem, that mechanic learns more about your motor[s]/situation, hopefully leading to the proper repairs. Sometimes it takes multiple repairs to get to the root of the problem? Is it possible that a part replaced may have been weak/bad from the factory, yes, and why it's important to return asap with as much input as you can give.

Good luck, post back on what you find out.

[redlowrey]

That is what you call the parts cannon fired at it, unfortunately a lot of those parts could have been tested, ether they were to lazy or didn't know how to. That 8.2 is a code for the shift motor ass, at least that gives you some direction to look at. When that code comes up the ecm has detected a problem with the shift motor ass, it will turn off the shift motor relay and it wont make any difference where the shift leaver positions are.
The shift actuator relay and the throttle body relay are supplied with battery voltage when the main control relay turns on, the ecm looks at the data sent by the bcm and if happy will supply the grounds to both the relays, and activate the throttle body and the shift actuator, did they do a voltage drop test on those or replace the relays. For it to come on at the dock for no reason could be as simple as the relay dropping out.
You have had everything replaced that would effect the circuit, it is going to be something simple.