Fuel level

[Boatman166]

I have a Suzuki 300 with the SMIS, 2 LMF 400 gauges, a GPS puck and fuel tank level sensor.
Every thing is 2009. About 18 months ago I updated some firmware when I had to replace one of the LMF400's and the fuel level sensor. Everything has worked fine since.....Until recently.

I can configure the fuel level on either gauge and it reads correctly in %.

Problem comes in the fuel burn display, which has always worked. It displays GPH correctly but the vertical bar graph on the right is now pegged at 100% and the full remaining never moves from 99,999gal and its an 82 gal tank.

I have reset the gauges and still have the problem. Problem is the same regardless of which gauge I set it up on.

I am thinking the SMIS is supposed to read the fuel level sensor when you do a Refill in Fuel System Settings but it is not or something has locked a bit up for that or something.

When it was working it was VERY accurate. I have reset everything from the gauge side. Can anyone recommend anything else?

Took it to my dealer and they said they no longer support Suzuki motors. Even though they are the ones that sold it to me!!!

Lowrance was helpful to the point of telling if the gauge reset didnt work I needed to call Suzuki. Start here because I have seen lots of helpful posts in the past

[Harper]

Did you indicate the fuel remaining source to the LMF400 as the fluid level sensor after the firmware update? It's part of the fuel setup page.

[Moonlighter]

Its very difficult to diagnose this and figure it out remotely.

But the basics are:

You have 2 sources of fuel data on your network -

1. The level sensor that is attcahed to the fuel tank sender unit; and
2. The calculated fuel remianing that is derived from the engine interface.

When both these sources are present, there is potential for confusion and conflict in the system. This is further complicated by the need for software compatibility between the different components...... so there are multiple variablesat play!

To start with, I would turn everything on, (engine key tirned on but not running is Ok) and do a "auto select" for data sources. Go into one of the SMIS menus, data sources, and find the option to auto-select or similar and do that. What it then does is to automatically select the logical data sources for the system to display. This can often rectify situations where data sources have been lost or corrupted - which can happen when software is updated or new devices addd to the network.

If that doesnt fix it....

Secondly, the issue could simply be that the tank sender unit has failed or a wire attached to it has got corroded or damaged. So check that out carefully and get a multimeter on to the tank sender connections.

If that doesnt fix it....

i would look at the Suzuki interface configuration - to make sure that the setup is still correct. Sometimes config settings can get lost. So, check that it is set as "1 engine/1tank", and that the tank capacity is set correctly. You would probably know that you need to go into the SMIS menu, device list, select the Suzuki, and configure.(doing this config in one gauge sets it for the whole network so, it doesnt need to be done in the second SMIS as well)

If that doesnt fix it....

If that checks out, I would then look at the fluid level sensor config - Ive not used these personally, but as you would know, they are simply working off the electric tank sender unit, and have to be calibrated/set up - so get the manual for the level sensor and follow the procedures to set it up and calibrate.

Try these things and let us know how you go.

[Boatman166]

Keeping my fingers crossed :-)

Ok,, here is what I have done....and I think it is fixed.

tried #1 all devices showed up and I could not find a way to "auto-select"

Skipped #2 because have checked that previously

moved to #3 this is where things got interesting.
Engine year was off by one year. Changed that
Reviewed 1 engine- 1 tank
went to the fuel use gauge and menu then fuel setup, went usage source, It was on tank level, change to calculated. Exit out all the way now gauge shows -84 gal. So since the level gauge indicated 47.5% (of 82 gal) so that equals 38.95 gal in the tank. So I added 84 to the 38.9 to get 122.9.

Then I went back into the fuel use gauge screen, menu fuel set up, and did a partial refill. Even though tank is only 82 gal this function let me enter the 122.9 gal, and ta da. The remaining bar graph display on the fuel use gauge now looks fine and the fuel level % did not change. I will take it out and do and actual Refill Tank this weekend to see if it will still track close to the actual tank level %.

Hopefully it will work and the little leprechauns will be purged for the season!!!

Thanks for the assist Moonlighter!!! I really appreciate it.

[Moonlighter]

Is the tank capacity set at 82 gal? That should be the thing to check.

The engine year setting is completely unrelated, I bet you a beer that if you go back into the device list you find it has reverted to what it was!

Anyway, let us know how you go on the test run. Hopefully you have got it sorted wuth the chnage to data sources.