2001 Optimax SmartCraft Wiring / Questions

[chackett]

Hi All-

I got a "new to me" 2001 Optimax. The fellow that I got it from had 2 Smartcraft gauges that came with it, a tachometer and a speedometer, but none of the necessary wiring or harnesses.
Doing all my own research, I basically got what I thought was needed, wired everything up and yesterday went for a test ride and the tachometer isn't working.
I bought a 15' 84-879968T15 - This is the cable that I ran from the cowling to the center console. It plugs into a junction box in console on one end and into a plug under the cowling on the other end. Then I got the Smartcract tachometer harness. It plugs into the gauge on one end and into the junction box on the other. All seemed good to me. When I turned the key to the on position (but didn't start since I wasn't on muffs or in the water), the gauge illuminated and the tach needle moved slightly. Felt like I was probably good to go.
When I lake tested it yesterday, the gauge didn't work. The small LCD screed is sunburned / faded, but I could at least see well enough to tell there was something there, although I couldn't tell what.
Other than the obvious (the gauge being bad), is there anything else I can check or any other ideas what might be going on or things to test. For example, does it matter which end of the long cable from the cowling to the junction box is on which end? I did notice there was a green band on one end of the cable, but both plug ends seem the same to me. Is there only one possible place to plug this cable in under the cowling?
I'd sure love to get this gauge working if anyone has ideas.
Thanks!
Chris

 

[alldodge]

Don't know how to test a smartcraft gauge by it self, but they all interpret data from the CAN network. If the network is connected correctly with a terminator then it should work.

 

[chackett]

Don't know how to test a smartcraft gauge by it self, but they all interpret data from the CAN network. If the network is connected correctly with a terminator then it should work.

I apprecate your taking time to reply. How can I confirm or validate that it's "connected correctly with a terminator?" Either the gauge doesn't work, or I have it connected incorrectly. What would the expected behavior be if it were not connected correctly? Would the gauge do anything at all if it were connected wrong? What does the terminator look like and where would I expect to see it?

 

[alldodge]

The terminator part number is list in pics. Note there is one on the motor and one on the junction box

 

[chackett]

Thanks again. I am believing now that my trouble is with the lack of a resistor. When I got the motor, the 10-pin CAN connector under the cowling was empty (no harness or resistor, just the plug). So there was no resistor for me to move to the junction box. The box just came with weather caps I believe. Also, the diagram in "smartcraft sys link.jpg" makes it look like the orientation of the cable matters, in that there is a resistor possibly built into the cable, so perhaps I also have the cable installed wrong.

 

[chackett]

I've been reviewing the documentation, and it seems a little thin to me But maybe that's because I'm dense.. who knows.
For example, in my situation, I'm only running one smartcraft gauge (the tachometer). So I have the cable from the cowling to the center console where it's plugged into a 4 port junction box. So one port has the cable from the cowling, one port has the tachometer harness, leaving 2 ports empty. Do both empty ports need a terminating resistor?
Also, as I mentioned, it's possible I have the cable from the cowling installed backward. When I installed the cable, I looked at it to make sure both ends looked the same, and generally they did. It's possible there was a colored piece of tape around one end of the cable, but there was definitely no "this end to motor" or "this end to gauges" type markings. From the diagrams, it looks like the "resistor" end of the cable has the resistor built into the cable? Is there some way to tell which end is which?
Thanks again!
Chris

 

[alldodge]

Think of the CAN buss as a hose filled with water and the terminator(s) seal the ends so the water will stay filled. If a terminator is left off then the water keeps pouring out.

You can use a 4 port junction box but all ports not used must have terminators for it to work. Also with just having one gauge the junction box is not needed (see pages 17 and 23)

 

[chackett]

Think of the CAN buss as a hose filled with water and the terminator(s) seal the ends so the water will stay filled. If a terminator is left off then the water keeps pouring out.

You can use a 4 port junction box but all ports not used must have terminators for it to work. Also with just having one gauge the junction box is not needed (see pages 17 and 23)

Thanks so much for the help, I really appreciate it. I'll go make the change and remove the junction box from the current install (although glad I have it for possibly adding the speedo in the future). Hopefully that'll get it sorted for me for the time being. I just hope I don't have to re-pull the cable from the cowling to the console

 

[QBhoy]

Is 2001 maybe a little early for smartcraft? I know it is on inboards anyway. But sounds like you have the network there to plug things into. So could be wrong.
What I do know around the terminator thing…is that some early compatible engines need to change terminator caps to the newer type. So on the mercruiser engines before 2005…they came with purple terminator caps. To work with smartcraft you need to buy yellow caps. May be the same here.
On the lcd gauge. There is a company in the US that can repair these. Gauge saver it might be

 

[chackett]

Thanks so much for the help, I really appreciate it. I'll go make the change and remove the junction box from the current install (although glad I have it for possibly adding the speedo in the future). Hopefully that'll get it sorted for me for the time being. I just hope I don't have to re-pull the cable from the cowling to the console

This stuff just gets more and more confusing to me. Although I might be getting a little clarity .. I'm not sure.

On page 4 of the smartwire.pdf is a diagram of the overall harness. I think part of my problem is that I can't locate the branch labeled "M" - the 10-Pin SmartCraft connector that's a branch from the 14 Pin connector at the engine. Since I hadn't been able to locate that, I ordered 84-879968T15 which is a 10-pin connector cable that goes from the engine mounted 10-pin CAN connector, to the console and plugs into the junction box. I can not use this cable to connect directly to the tachometer harness because both ends are female.

Is there such a thing as the main 14-pin harness that doesn't have the 10 pin CAN connector on it?

I'm also surprised that on page 14 where it talks about "Junction Box Install" it doesn't say unused connectors need resistors, but instead just says "weather caps." I'm more than happy to buy a handful of resistors and put them in all the unused ports, but this makes me think my problem is something else (like that I can't find the 10pin connector off the main wiring harness.)

Thanks again for all your help, I appreciate your attempts to educate me

Chris

 

[chackett]

Is 2001 maybe a little early for smartcraft? I know it is on inboards anyway. But sounds like you have the network there to plug things into. So could be wrong.
What I do know around the terminator thing…is that some early compatible engines need to change terminator caps to the newer type. So on the mercruiser engines before 2005…they came with purple terminator caps. To work with smartcraft you need to buy yellow caps. May be the same here.
On the lcd gauge. There is a company in the US that can repair these. Gauge saver it might be

This engine definitely does have SmartCraft, even if I'm not currently smart enough to figure it out lol. The connectors are there, the motor came with smartcraft gauges, and the various smartcraft harnesses and junction boxes all fit.

Based on the help I've been getting from alldodge, I think I'm working with 2 main problems now. 1. I can't locate the 10 Pin connector that's part of the main wiring harness (not the engine mounted connector). And 2- Since I can't find that, and I'm USING the engine mounted CAN connector, there's at least one, maybe more, resistors missing.

 

[alldodge]

The first part of the manual talks about a harness that is not using smartcraft but is ready (so to speak). This continues how to wire thru page 34. Shows if junction boxes are there but not being used so weather cap is all that is needed. Connector M on page 4 is needed if that type of cable is installed. J box not needed with just one gauge

I should have looked up the cable you listed before proceeding but assumed you were talking about the correct cable. Prior to 2002 the motor used cable 879981T with built in terminator on motor end only. I didn't notice your using the newer 2002 and later cable. The newer cable 879968T15 has a built in terminator on both ends as I understand it.

I'm not an expert with smartcraft

 

[alldodge]

Found some more info but this list 2006 and on

 

[alldodge]

Resistors

 

[chackett]

The first part of the manual talks about a harness that is not using smartcraft but is ready (so to speak). This continues how to wire thru page 34. Shows if junction boxes are there but not being used so weather cap is all that is needed. Connector M on page 4 is needed if that type of cable is installed. J box not needed with just one gauge

I should have looked up the cable you listed before proceeding but assumed you were talking about the correct cable. Prior to 2002 the motor used cable 879981T with built in terminator on motor end only. I didn't notice your using the newer 2002 and later cable. The newer cable 879968T15 has a built in terminator on both ends as I understand it.

I'm not an expert with smartcraft

Well, you may not be an expert, but you clearly know more than I do, that's for sure. I appreciate the help you've given. I've been really surprised at how little information I've been able to find on-line regarding all this.

My engine is a 2001, so who knows, maybe I ordered the wrong cable. But when they reference "the blue 10-pin cable" that sure looks like what I have. The cable I ordered doesn't have any "obvious" markings on it that would indicate it matters which way it is installed. I ran this blue cable from the engine mounted 10 pin CAN connector to the single helm at the center console. I assumed I needed the junction box because the end of the tachometer harness and the end of the blue 10 pin are both female. So the junction box is really just a gender bender for me I guess.

The only marking on the blue cable that would lead me to believe one end is different is that one end has a small green band around it. The other end does not. If there is an "inline resistor" on either end, it's not obvious by visual inspection.

In your "resistors" screenshot, I'd have to believe I have the cable depicted in the lower photo. There appear to be the CAN P or 2/3 PIN pigtail connectors on the upper cable, and my cable definitely doesn't have that.

Sincerely .. thanks for the help so far, I really do appreciate you trying to help me out.

Chris

 

[QBhoy]

This engine definitely does have SmartCraft, even if I'm not currently smart enough to figure it out lol. The connectors are there, the motor came with smartcraft gauges, and the various smartcraft harnesses and junction boxes all fit.

Based on the help I've been getting from alldodge, I think I'm working with 2 main problems now. 1. I can't locate the 10 Pin connector that's part of the main wiring harness (not the engine mounted connector). And 2- Since I can't find that, and I'm USING the engine mounted CAN connector, there's at least one, maybe more, resistors missing.

No worries. If you’re still struggling with it tomorrow. I’ll go look at the set up on my smartcraft gauges in the merc outboard I have. Just let me know if you want photos

 

[alldodge]

The older cable 879981T will have a label listing terminator end
https://www.mercruiserparts.com/879981t10-harness-assy

The newer cable does not
https://www.mercruiserparts.com/879968t15-harness-assy

 

[alldodge]

Just let me know if you want photos

Hey I want photos, can always use more info

 

[QBhoy]

Hey I want photos, can always use more info

No probs. I’ll get a look in about it within a day or two. Never actually looked at the set up it has. Was all there when I bought it.
I fitted the smart craft to the mercruiser mpi boat though. Being a 2003. It needed a yellow terminator cap to work. Came with purple originally. That was for vessel view system to work at least.

 

[chackett]

The older cable 879981T will have a label listing terminator end
https://www.mercruiserparts.com/879981t10-harness-assy

The newer cable does not
https://www.mercruiserparts.com/879968t15-harness-assy

Wow .. ok .. I had no idea there were different versions of that cable. So I obviously have the newer one that doesn't have any resistor in-line.. Does this mean I have the wrong cable, or do I just need to add an external yellow cap resistor to my junction box, do you think?
Thanks you!
And thanks QBhoy - I would also appreciate any photos. The more I see, the more I learn for sure. Thanks!

Chris