Help with Twin 2013 Suzuki DF 250 AP and engine interfaces with different softwares

[Mombo31]

I am new to the forum so looking for help on a 2013 twin DF 250 AP with 4 SMIS gauges. Recently my port engine interface went bad and the gauge stop showing RPM, voltage and engine temp. Went to order a new EI from Brownspoint where it showed I should buy a interface with V 3.5. I replaced the bad one with the new one and immediately the RPM, voltage and engine temp started to show up. However, while the key was in on position but engines not running I noticed a 6-7 degrees difference in the engine temp (new EI showing less temp) from the starboard engine.

My starboard engine has a V 2.7 interface connected. Have few questions:
1. Can my engines work fine having one EI with V 3.5 and other with V 2.7 in the same network?
2. Could the difference in engine temp be related to the software version differences? So far I have not had temp issues with the V 2.7.

My boat was in the trailer and I could not start both engines at the same time so could not compare engine temps while running but at least while off with key in on position I noticed the temp difference. When I started the port engine with the new EI I did not notice any issues in the reading but cant tell if the engine was 6-7 degrees hotter than what the gauge was showing.

Could you please help me on this issue? Thanks a lot.

[Moonlighter]

I think it is possible that the newer interface software takes engine temps from a different sensor.

I do know that my DF115 running Interface version 2.5.0 shows a significantly hotter temp than engines running later versions such as 2.9 and 3.5. Asked my mechanic and he said its data sourced from a different sensor. Eg one could be cylinder head and one could be water jacket.

I would not worry too much about it, just be aware. The temp alarm codes etc will be set relative to the software version being used. Just try it out and see how it goes.

[Mombo31]

Many thanks Moonlighter. Will give it a try for some time to see how it works.

[Moonlighter]

Many thanks Moonlighter. Will give it a try for some time to see how it works.

Ok let us know how it goes.

Cheers!

[Mombo31]

Just if I decide to buy another interface, should I go back and buy a v2.7 to match the original ones or should I buy a v3.5 to have both upgraded? What are your thoughts?

[Moonlighter]

I would get a new 3.5.4 cable.

It will be almost impossible to find a older cable running V2.7.0 software, its the .luf file version and they simply arent available. Not sold since back in 2016 or even earlier. The new cables run the .swup file version..

In fact I am somewhat surprised that the original cables you had are V 2.7, if the motors were installed in 2013 its surprising that they used those cables.

[Mombo31]

Interesting.. Engine interface2.jpgWent to check again and in fact they are v2.7. I bought the engines used in 2015 with all wiring included.

[Moonlighter]

Ok, but just because it says 2.7 on the cable does not mean that its necessarily actually running 2.7! The software version can easily be changed by uploading a different version.

I dont think that the SMIS gauges can show you the actual interface version. But, if you also have a Lowrance or Simrad display on your network, its easy to check. Just turn the engine key on, and in the Lowrance or Simrad network menu, open the device list, select that engine, open it and select configure. It pops open a screen that shows you all details including the interface software version.

Those old interface cables running .luf software are rare as hens teeth and command a high price on the used market, because they are the only cables that work with pre-2008 engines.

FYI here is a link to the official Suzuki/Lowrance page that shows the 2 different types of interface cables and shows the correct software versions depending on engine year/serial number. You can also download the relevant software files from there. But NOTE: you cannot load .luf software onto a .swup cable and vice versa.

http://ww2.lowrance.com/Suzuki