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Boat side of Crusader harness RA121079 Male connector

dfswan

dfswan

Member
Good morning. I have a Crusader 5.7 MPI 2005 (330HP) with a bad starter connector on the instrument/boat side of the RA121079 engine harness. I'm looking for the mate of the 10 Pin Femail harness on the boat side of the connector. In a perfect world, I would replace the whole harness, but finding a harness for a 2005 Shamrock 246 is close to impossible. Next would be a 10 pin Maile with 12" Pigtail similar to the mercury interface shown. Here is a picture of the existing Maile plug as well.

I can't even find a part number. I have a vendor contacting PCM to see if they can be any help. They have been pretty worthless to me, but perhaps I'm not communicating to the right people.

Any thoughts or suggestions?
 
if the issue is in the instrument side of the wiring harness, it would be much faster and more economical to just run a new wire from the ignition switch to the starter and tape it to the existing harness....just my 2₵...
 
makomark said:
if the issue is in the instrument side of the wiring harness, it would be much faster and more economical to just run a new wire from the ignition switch to the starter and tape it to the existing harness....just my 2₵...
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No Doubt. This harness has been cut and spliced once before I got the boat and I'm concerned that it might happen again if I just replace the one wire. There is a lot going on with this plug and harness, and I want to be as reliable as I can be. ...but, if I can't find the connector or the extension, I will probably do just as you suggested.

Thanks for the input.
 
if one of the splices failed, the others aren't likely too far behind...If you want reliability, the fewer connectors, the better....
 
Thanks for your thoughts. I got a picture of the wiring harness for the 2006 Model, and sure enough, it doesn't use the female 10 pin connector. The 2000 - 2005 use the RA121079 Engine Wiring Harness Assembly (With round 10-pin boat harness connection) Earlier models use the 10-Pin as well. PCM contacted my vender, and they attempted to tell them the RA121093 which is a female connector to convert the old Boat side Male 10 pin Harness to the newer style Crusader Engine harness. would work. It obviously wont. I hate to tap into the Engine harness. If I can't find it I'll probably run another wire from the Key to the Starter as makomark suggested above.


This is what I'm looking for.
 

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The full 10 pin harness hasn't been used in a long time, even PCM/Crusader didn't use all the pins. Pin 10 went away because it just wasn't needed by VP and Merc. Pic is shows pins 4, 9 and 10 not used for the carb model.

Look at the back of your plug and count the number of wires. If there are just 9 or less then pin 10 is not used and can verify by ringing out the connections

PCM Crusader 10 pin.jpg
 
FWIW, there used to be a member here named 'linesix'...he runs linesix services, in mullica hill NJ and last I checked was still in business. Rick has a wealth of Crusader knowledge and I'd bet he can tell you what you need...look him up on the internet and give him a call...
 
AllDodge said:
The full 10 pin harness hasn't been used in a long time, even PCM/Crusader didn't use all the pins. Pin 10 went away because it just wasn't needed by VP and Merc. Pic is shows pins 4, 9 and 10 not used for the carb model.

Look at the back of your plug and count the number of wires. If there are just 9 or less then pin 10 is not used and can verify by ringing out the connections

View attachment 34189
Click to expand...
Here is the pinout for the 2005 5.7 MPI. I can see Mercury not even having a pin 9 but I believe that is active on the Crusader.
1736111965081.png
 
makomark said:
FWIW, there used to be a member here named 'linesix'...he runs linesix services, in mullica hill NJ and last I checked was still in business. Rick has a wealth of Crusader knowledge and I'd bet he can tell you what you need...look him up on the internet and give him a caI
Click to expand...
I found him and sent him a note. We'll see how it goes. Thanks for pointing me in the correct direction.
 
I noticed that the Volvo Penta Main Harness Adapter 14 to 10 Pin 3884406 (Female) has the same connector to attach the engine to the dash. Apparently, this Dash to Engine Harness/connector I'm looking for is not just with Crusader Engines.
 
OK, just to finish up, I found a 9 pin round male connector and wire on https://michiganmotorz.com/ with variable lengths (3'-35') and I'm probably going with a 10' for $100. it is missing Pin 10 which according to my Pin-Out for this 2005 Engine, is a 'Data Line'. (777-6118-XX)

Does anyone know what the 'Data Line; does?

It sure would be great to be able to connect to a NMEA to get Fuel Flow readings to my MFD Chartplotter. It is a Orange and Black wire on the engine harness (RA121079). Worst case I can tap into that in the future if I need to without disrupting any primary engine function.

Thanks for all the help and feedback everyone. If for some reason this doesn't work, I'll let everyone know.
 
"Data Line" should be the serial data stream from the ECU. You can verify its function with a continuity check between the pin in question and the DLC or the ECU connectors...if you need the pin outs for either, they are in the ECM manual...
 
AllDodge said:
I went to MM site and looked at the 3-35ft cables, and think your mistaken in which pin is not there. Its not pin 10 its 9 (Your check engine)

Pin 9 is in between the 2 larger pins (1 and 6) and is the same pin out shown at Hardin marine
https://michiganmotorz.com/i-o-engine-wire-harness-options-3ft-35ft/
Example pic
View attachment 34208
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I would say you are correct, and I stand corrected. The Pin in-between the two large pins is missing on the MM Harness.

It gets pretty confusing with the engine side (Femal) and the harness side (Male) Your diagram appears to be on the Engine side (Female) similar to the installation Manual shown below:
1736433384401.png

Note the cable is the inversion that:
1736433772770.jpeg
1736433835219.jpeg

My existing cable.

All of that being said, how critical is not having an engine light?
 
makomark said:
"Data Line" should be the serial data stream from the ECU. You can verify its function with a continuity check between the pin in question and the DLC or the ECU connectors...if you need the pin outs for either, they are in the ECM manual...
Click to expand...
Please exsuse my ignorance, but where did you get the ECM Manual? I can imagine that being very valuable.
 
BTW, Good news is that the ECM model (MEFI-4) should be compatible with a gateway to make it compatible with NMEA 2000. That means all the functions of engine including fuel flow, and Fault Codes, that are not easily obtainable. That will be my next project if it is actually compatible. I'm looking forward to finding and reading the ECM Manual.
 
Guess it depends upon the data source used...the L510001-05 owner's manual (2005 MPIs) shown pin 9 as the CEL in figure 16-1, on page 84...that said, they figure is labeled Typical Instrumentation Wiring....
 
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