NMEA-2000 Connection to Legacy E-TEC Engines; Alternative Methods

Information about Evinrude I-Command, ICON Pro, and ICON Touch Color Displays
Posts: 6019
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula

NMEA-2000 Connection to Legacy E-TEC Engines; Alternative Methods

Postby jimh » Fri Sep 08, 2017 10:49 am

This article describes two methods for connecting a legacy E-TEC to a NMEA-2000 network that avoid having to buy an expensive specialized cable.

Legacy E-TEC engines (now often called "G1" engines) have a NMEA-2000 communication port on their engine management module (EMM) that uses a non-standard connection, that is, the connector is NOT the now standard DeviceNET Micro connector found on almost all other NMEA-2000 devices and also on the latest generation of E-TEC engines (the G2 engines).

Because of the non-standard connector at the EMM, a special drop cable must be used to connect the engine to the NMEA-2000 network backbone, which is almost universally wired with the standard DeviceNET Micro wiring devices. This specialized cable is available only from two vendors, Evinrude and Lowrance. The Lowrance version sells for an MSRP of $100 and includes one network T-Connector. See an Evinrude dealer for price of the Evinrude-branded cable, which is otherwise identical to the Lowrance. The cost of this one cable is greater than the cost of the typical NMEA-2000 network starter kit, which sells for about $60 and includes several cables, several network T-Connectors, and a power node connector.

There are two alternatives to buying the rather expensive special E-TEC drop cable, and both can reduce the costs, albeit at the expense of some added labor.

The first alternative method is to sacrifice an existing DeviceNET pre-made drop cable, and modify it to become a specialized drop cable for the E-TEC, making your own specialized drop cable for just the cost of one connector. This can be accomplished by cutting off the DeviceNET female connector at the cable end, and replacing the DeviceNET connector with the specialized connector needed to mate with the E-TEC EMM wiring harness connector for the NMEA-2000 port. The cost of the components for the necessary connector are about $5, however it can be tedious to order these and some skill is necessary to assemble the new connector. In this method there is no modification to the E-TEC.

The second alternative method is to modify the E-TEC engine wiring harness to have the standard DeviceNET Micro connector. There are now field-installable DeviceNET Micro connectors available. The existing non-standard connector on the E-TEC wiring harness would be cut off, leaving four individual conductors, which will be wired to a new connector. A Male DeviceNET Micro connector is installed on the E-TEC wiring harness conductors. The insulation wire color is the guide for how to connect the conductors to the poles of the DeviceNET connector. For guidance, see the separate article on DeviceNET MIcro connectors and wire colors. The cost of a field-installable connector is about $20. In this method, a standard drop cable can be used, but the engine has been modified.

Of the two methods, I tend to prefer the first method. It costs less and makes no modification to the E-TEC. However obtaining the connector is more difficult, and assembling the connector is more difficult. And you also have to sacrifice an existing drop cable. But the total cost of this method will be $5 to $8 and any shipping charges to get the connector.

One source of the proper connector to convert an existing drop cable to a specialized drop cable for E-TEC is MOUSER ELECTRONICS. Here is a possible parts list with their part numbers:

Connector seals = PN 571-2819342
Connector pin contacts = PN 571-183024-1
Connector body = PN 571-282106-1


The second method is perhaps not as desirable because it makes a modification to the E-TEC wiring. However, Evinrude has now switched to using the DeviceNET Micro connector for the NMEA-2000 interface in their new G2 engines, so using this method is just, perhaps, a way to update a G1 to the latest configuration for NMEA-2000. With this method, you have to also have a standard drop cable to run to the engine.

MARETON field-installable MALE DeviceNET Micro Connector, about $20
maretronDeviceNetMale.png (23.39 KiB) Viewed 1081 times

A source of a DeviceNET field-installable connector is from MARETRON. Here is a link to a vendor that sells the connector:

https://www.westmarine.com/buy/maretron ... ecordNum=3

Be sure to order the proper gender; you want a MALE connector to be installed on the EMM harness.

Regarding the connector genders, the standard arrangement in NMEA-2000 network wiring is for the NETWORK port for a device to connect to will have female electrical contacts. This is done because the network is delivering power to the device, and any connector carrying power usually carries the power on recessed female contacts so that the power contacts are not exposed to accidentally coming in contact with another conductor. Curiously, Evinrude has wired the E-TEC EMM harness connector for the NMEA-2000 connection with a female connector. This requires the specialized drop cable to have a male-to-male connector arrangement. This is odd for two reasons: all other cables in the network wiring are male-to-female, allowing easy joining and extending of cables, and all exposed connectors carrying power are usually female (if the power node is inserted at one end of the network and properly oriented). Thus, if leaving the E-TEC wiring unmodified, you will make a male-to-male specialized drop cable, but if modifying the E-TEC you will replace its female connector with a male connector.
AmpSeal 1.5 four-pole MALE connector for connecting to E-TEC engine; seals, contact, and body are shown.
ampSeal_1.5-connector.png (48.57 KiB) Viewed 1070 times