Trim not work above 3000rpm (377Mag MPI DTS Axius)

[silver_power]

Hello. I recently bought a used cobalt 303 with dual 377Mags Axius DTS.
The boat runs fine except i have a problem (different thread) with the axius ...
But i have another issue. The trim does not work above 3000rpm's. Nor up or down. At 2990rpm works fine, but at 3000rpm nothing. Something cuts it.
My mechanic told me that this happens at engines equipped with DTS for safety reasons , but i do not believe it. I want to trim down to get on plane and after i want to trim up for better fuel efficiency or top end...... But i can not do it...
The starboard trim sender has an issue and sometimes throw a fault, but only at starboard engine. The problem happens at both engines simultaneοusly .
Do you know why this happen and mostly, do you know if this happens by default at DTS engines??
Thank you very much.

 

[alldodge]

Would be a question for @muc or @Fun Times

 

[tpenfield]

You should certainly be able to trim down at any RPM, but not up past a certain point at cruising speeds. (trim limit)

I have trimmed up on my boat at 3600 RPM . . . of course the boat slowed down, so I trimmed back down and the boat re-gained its speed. (I have the Merc 6.2 ECT SeaCore w/ DTS, Axius, Joystick, etc. . . )

You mentioned the starboard engine trim sender having an issue. You probably need to get that fixed and adjusted properly, then see where things stand.

You might want to review this with the mechanic while you are at it.

 

[Fun Times]

You both might have an interest in knowing about Merc active trim system if you don’t already have it.

Mercury Marine Introduces Active Trim System

During its media event in Charlotte, N.C., this week, Mercury Marine demonstrated its new patented Active Trim system that—according to a press release from the company—“automatically delivers instant, effortless trimming of boat engines.” The system will be available for new Mercury...

www.speedonthewater.com

Silver power, though you may not have active trim here’s some general info of how to set the active trim system up and maybe you’ll happen to see something that can help guide you and your tech down in the lower pages…,

http://download.brunswick-marine.com/filereader/file/pdf/4/enen/smartcraft/2016/8m0120820r.pdf

RELATED DOCUMENTS

• Active Trim
• Active Trim Owner's Manual
• Active Trim Quick Reference Guide
• https://www.mercurymarine.com/en/ca/gauges-and-controls/steering/active-trim/

Bear in mind that there’s a chance that both trim systems are connected to each other via a wire harness so that it could be that if one sensor goes bad it could affect the other side too…From the guide above for an example: #5. For existing installations, disconnect the dual engine power trim adapter from the port and starboard power trim extension harnesses.:

Were you ever able to locate any type of service manual guides for the Axius system?

I’d say your service tech is half correct that it is a safety feature but only because the The PCM is sensing somethings wrong and it won’t allow trim over 3k until what’s ever wrong is right again.

I thought you had the Diacom software to help read issues, etc.?

Rinda Technologies Inc.

 

[tpenfield]

Not sure if my boat has the active trim, unless it is part of the Axius 'Eco' system (which I have yet to ticker with).

I have a manual for the Axius (Gen 2) that came with the boat.

 

[muc]

So much depends on what Axius your boat has. Your tech could be right. Only problem I see at this point, the tech should have corrected a known fault (trim sender) before proceeding with anymore diagnosis.

If you think about how this system works to allow joystick control. The drives can hit each other during operation and cause big damage. If you look in your owners manual, you will see a recommendation to secure the drives during transport so they don’t get damaged.

So to keep this from happening the programmers had to start disabling certain things when the computers don’t get valid feedback from the sensors. This incentives the customer to get their boat serviced. Ha Ha, just half kidding on that. They’re really just trying to keep the boat from damaging itself.

Welcome to the world of can buss technology! Everything is interconnected.

Had one boat that the engine wouldn’t engage the starter due to a bad trim sender. Guessing the programmer didn’t want you to crank the engine when the drive was tilted up. They disabled that feature when the next version came out.

Fix the trim sender and go from there. Probably will correct this issue.

 

[muc]

And P.S.
you should probably combine the threads if your other problems concern Axius. Like I said, everything is becoming interconnected.

P.P.S. @tpenfield did you get your issues fixed? I don’t get the time to check the forum like I used to.

 

[tpenfield]

P.P.S. @tpenfield did you get your issues fixed? I don’t get the time to check the forum like I used to.

Yes, I doubled up on the accessory battery and the warnings went away. (actually connected the bank of 4 inverter batteries to the 1 accessory battery). It seems that part of the overall system is fed from the 'house' battery and not the starboard engine battery. I was also able to resolve the warning if I connected the Acc. battery and the Stbd engine battery together. I just felt combining the inverter and the accessories was a better way to go.

I've heard similar tale on a Formula boat (my boat is Cruisers Yacht), where the 'accessory' CB popped and the owner was getting the 'Critical Voltage' warning. He reset the CB and all was good.

So, there must be a disconnect between what Mercury is saying about a single clean voltage source and what the boat manufacturers are actually doing.

Regardless, it seems that the conditions for the warning are when the engine battery is sitting at its resting voltage (12.6) and the accessory battery is a little bit weaker . . . then the voltages that the PCM is seeing from the 2 sources is low enough and of enough of a difference that it triggers the warning.

My solar battery charging system is keeping the entire set of batteries at a high enough voltage, that the PCM is happy with it, even though there is still a difference between 'system' and 'battery' voltages at the PCM.

 

[muc]

So, there must be a disconnect between what Mercury is saying about a single clean voltage source and what the boat manufacturers are actually doing.

That's an understatement! I spent 25 years at new boat dealerships trying to correct these types of issues before the customer found them.

I highly recommend you get your boat wired per MerCruisers requirements, it will help at a later time ---- trust me.

 

[tank1949]

You both might have an interest in knowing about Merc active trim system if you don’t already have it.

Mercury Marine Introduces Active Trim System

During its media event in Charlotte, N.C., this week, Mercury Marine demonstrated its new patented Active Trim system that—according to a press release from the company—“automatically delivers instant, effortless trimming of boat engines.” The system will be available for new Mercury...

www.speedonthewater.com

Silver power, though you may not have active trim here’s some general info of how to set the active trim system up and maybe you’ll happen to see something that can help guide you and your tech down in the lower pages…,

http://download.brunswick-marine.com/filereader/file/pdf/4/enen/smartcraft/2016/8m0120820r.pdf

RELATED DOCUMENTS

• Active Trim
• Active Trim Owner's Manual
• Active Trim Quick Reference Guide
• https://www.mercurymarine.com/en/ca/gauges-and-controls/steering/active-trim/

Bear in mind that there’s a chance that both trim systems are connected to each other via a wire harness so that it could be that if one sensor goes bad it could affect the other side too…From the guide above for an example: #5. For existing installations, disconnect the dual engine power trim adapter from the port and starboard power trim extension harnesses.:

Were you ever able to locate any type of service manual guides for the Axius system?

I’d say your service tech is half correct that it is a safety feature but only because the The PCM is sensing somethings wrong and it won’t allow trim over 3k until what’s ever wrong is right again.

I thought you had the Diacom software to help read issues, etc.?

Rinda Technologies Inc.

That's a PROBLEM with all this automatic stuff.... It fails and hard to debug.

 

[Grub54891]

Yeah, that 5? Volt reference on sensors can be daiseychained in some applications. Trying to find it is a nightmare.