Trim issue Smartcraft question for Don

[Sybmaster]

Hello to all,

My motor is a 2016 merc 90EFI 2.1L Four Strokes purchased new in 2018.

SN 2B215991

I have read many posts of this forum in hope of finding someone who had my issue;

My boat came analog gauges which I decided to replace with a set of smartcraft SC1000 tach. and speedometer plus SC100 trim gauge

(BTW thank you to this forum where I finally found the correct information to connect my Garmin GPS to the speedo input so the gauge displays GPS speed)

My trim problem is that the trim gauge does not react from the zero position (trimmed all the way in/down), the needle starts to move only when the motor is trimmed up about 10 degrees, and it is not a calibration issue:

The trim sender on the bracket is PN 8M0083396 rev.E

This sender has 3 wires (purple 5 volts, black 0 Volts/ground, brown/w signal out)

This sender is analog has I get 30 ohms trimmed down and 210 ohms all the way up at trailer position, (I do not get a 0-5volts out)
It is not a mechanical sender pot a slotted shaft that rotate with position of the shock rod, it is a flat sensor that sits flush with the non-slotted side of the shock rod. I read that the shock rod is magnetised, so the sender probably has some array off hall-effect sensors..

So I purchased a A to D converter (with limit stop, kit PN 8M0118725, the actual number on the module itself is 8M0118586) where the brown/w output of the sender connects to the brown/w input of the converter, and the yellow wire from the converter to the glorious yellow wire going to the ECM!

So the issue is that the voltage output of the converter (yellow wire) is at about 4 volts at trailer position which is fine but when I trim down the voltage drops gradually and then reaches 0.8-1.0 volts at about 10 degrees from behind all the way down.
if I continue to trim down to minimum the voltage does not move lower than 0.8-1.0 volts as if there a clamping diode as part of the internal circuit of the converter so I lose the first 10 deg indication.

At first I thought I could maybe rotate the shock rod to create a position offset so the minimum 0.8-1.0 volt of the converter would coincide with the "all the way down" position but cant do because the trilobe pin locks it in place..

I can not see how to resolves this ...

is there a different sender I should use with the A/D converter ? is it the wrong converter? maybe a digital sender instead that would connect directly to yellow wire of ECM? (but then I would lose the tilt limit stop)

In the sensor test section of my mercury motor service manual it says that the trim sender should have an output signal of 1 to 4 volts which coincide with the voltage swing observed at the output of the converter...but the manual does not have any part numbers so I don't know what sender they are referring to since t one mounted only gives variable resistor...

Any help would greatly be appreciated...

Thank you,

[bshort]

There is a digital trim sender available.

[MichaelJ3]

Not trying to answer for Don, he is definitely the expert, and would know if the A/D option you installed for trim limit works to get trim position onto SmartCraft network.

In case you were looking for an answer sooner, there is some info in the SmartCraft Options Sticky on the 3.0L Forum, --> http://www.bbcboards.net/showthread.php?t=894952
In Post 1 of that thread, it shows a photo of the Digital Trim Sender.
It is my understanding that you need the digital Trim Sender to get Trim Data on SmartCraft
Parts Dept at European Marine would be able to tell you which P/N you need for your motor and the price, gut says it is in the $100 range...

I assume you went through the SmartCraft Trim Cal procedure since you said it wasn't a Cal Issue (See your Gauge Owners Manual for Info).

Did you get the Digital Water Pressure sender? You need that too, if you want H2O pressure on your SC gauge. Thinking that was around $85 from my dealer a couple years back...

Good Luck, I love my SC-1000's

[Sybmaster]

Thank you MichaelJ3 for the help,

yes I seen this picture already, the sender on the picture is what I call a mechanical sender where the middle has a flap tat fit in the slot of the shock rod to rotate with the shock rod as the motor goes up and down.
y sender has a flat surface with no moving part, it seems to be a magnetic pickup (maybe Don could confirm this as well) . The end of the shock rod on the sender side is total flat and could not drive any mechanical sender (analog or digital).
The other end of the shock rod does have a slot but there is no mounting holes to mount a sender on that side. I wonder if I could flip the shock rod around to get the slotted end on the side with the mounting holes...(?)

Yes everything does calibrate perfect, the issue is really that he voltage stop lowering below 1.0volts at a certain point even if have another 10 degrees to go before the trim is all the way down...

Yes I got the digital water pressure sender with the A/D kit, works perfect!

I love my SC-1000's too especially (with the upgraded glass lens, even on the SC100!) with full band GPS speed on the speedo !! (no paddle wheel or digital pitot needed with latest mercury firmware, displays GPS straight from O mph/kmh)

[EuropeanAM]

Digital trim signals will not drop below approximately .8 - 1.0 Volts. I would strongly recommend you NOT continue attempting to test in this area as there is a potential of backfeeding into the PCM 5V Reference Circuits (and damaging the PCM).

Once the converter is installed, utilize the INSTRUCTIONS to set the TRIM LIMIT. The converter outputs BOTH and Analog and a Digital Signal.

On your Smartcraft Instrument, go through the Calibration Steps for ALL THREE positions (keep in mind, for DOWN you must go all the way down and STALL the trim for 4 seconds against DOWN).

SAVE each position.

The watch the readings (0-25) on the Smartcraft Instrument. "10" would normally be the end of the TRIM range (20 degrees approximately from FULL DOWN).

[Sybmaster]

Hello Don, ok thank you for the warning! I will not force anything below .8, now at least I know that it is normal.

Yes converter is installed and trim limit position is set, that works perfect.

Could you please be more detailed about "and STALL the trim for 4 seconds against DOWN" ? I'm guessing you mean keep the finger on the trim down switch constant for 4 seconds ?

if so, could explain what the constant 4 seconds "down" will do different?
When I calibrated the first time I did all 3 positions carefully (but id not hold down for 4 seconds), I just set it down and cal'd that position and then moved to the next..

thank you,

[EuropeanAM]

Newer PCM Calibrations can ascertain that the trim is running "down" but the sensor counts have stopped changing. This permits the PCM itself to "realize or recognize" the Full Down Position (a different process from your Smartcraft Instrument's Calibration, which is a process in the instrument itself).

Yes: Hold switch DOWN for 4 seconds with your finger (after reaching the full down position).

[Sybmaster]

Hello Don, so I had my hopes up but unfortunately it did not change anything, same problem even after holding the trim down for 4 seconds before calibrating trim on SC1000.

I have more data:
at trailer position, output voltage of A to D: 4.22Vdc in ref to ground (black /green stripe), needle of sc100 at trailer pos
at position 10 ( about 20 deg from full down) output from A to D: 1.51Vdc, needle of sc100 at 10
as I head toward full down , the voltages drop gradually...
at about 10 deg from full down the output of the A to D its 0.8Vdc, needle of sc100 now at zero
as I continue towards full down, the output from A to D still at 0.8Vdc, needle of sc100 at zero
then at trim full in, voltage output still at 0.8Vdc, needle of sc100 at zero

(when I disconnect the sender from A to D and measure Resistance between black wire and brown wire I get about 212 Ohms at trailer position and it slowly goes down to 24 Ohms when trimmed all the way down, but it’s gradual all the way down, it does not stop going down at 10 deg from full down like the voltage does at output at A to D when it is connected to the sender...

so exact same problem ...

any ideas?

thank you,

[EuropeanAM]

Sounds like a sender or crosspin (Upper Pin, Shockrod) problem.

Make sure the crosspin is properly retained by the Tri-Lobe Pin (pin not sheered off or missing).

[Sybmaster]

Hi Don, yes I checked all this, the tri-lobe is there solid, shockrod is good too.

If I m going to replace the sender to see I that I the problem, might has well just get a digital one and remove the A to D is there a digital sender available for this motor?
would you have the pat number?

thank you,

[EuropeanAM]

The 8M0087542 A-2-D and Limit Kit is the recommended method for Digital Trim. Sender is ANALOG.