2005 Mercury 4s EFI tiller bad plug on Engine Harness Connection

[rhalter]

Yesterday morning heading out for fishing turn the key and nothing, was thinking battery so tried backup and still nothing. Turns out the 20 amp main relay/accessories fuse was blown in the fuse holder assembly. Put a new fuse in and again as soon as I turned the key it blew again.

Did a little snooping around today looking for a bad wire or something and found that the #6 receptacle on the Engine Harness Connection that connects with the remote control going to the ignition box is bad. It's completely burned out, I'm guessing this is where the problem is.

Does anybody know which wire would run into the #6 receptacle? I cant find anything in the service manual. I'm thinking purple? Looking for any input and possible fixes. Changing out the engine harness looks like a giant PITA and maybe a little beyond my realm of capabilities.


Blown receptacle

 

[wired247]

Re: 2005 Mercury 4s EFI tiller bad plug on Engine Harness Connection

Its the black and yellow kill wire. You can wire around the plug and receptacle set . Peel back the insulation on both sides. Cut the black and yellow wire and solder in a jumper wire between the two wires. That is if the wiring didnt burn up because the ignition switch fried which it may have. In that case you will be replacing that as well. It could also be the wiring inside the control unit. Everything gets twisted around so bad inside those control units its almost a matter of time until the wrong wires insulation wears and it gets grounded out. The harness wiring then burns up in the weakest connection point where the plug is.

 

[rhalter]

Re: 2005 Mercury 4s EFI tiller bad plug on Engine Harness Connection

Does anybody have a diagram for which color wire runs into each # receptacle? I plan to give mercury tech a call tomorrow because I cant find anything in the service manual about which wire runs into what number receptacle. This is for a 2005 30hp 4s efi mercury. 8 pin engine harness to remote control connection.

 

[carholme]

Re: 2005 Mercury 4s EFI tiller bad plug on Engine Harness Connection

Are you using the Merc manual 90-857046 and if so, you should find what you need in 2D. What is your engine s/n?

Gerry

 

[rhalter]

Re: 2005 Mercury 4s EFI tiller bad plug on Engine Harness Connection

90-883064 is the manual number

1B199798 is the serial number

 

[carholme]

Re: 2005 Mercury 4s EFI tiller bad plug on Engine Harness Connection

Your s/n comes up as:

MERCURY - ( 30EFI H.P. (2005 ))
Serial No: 1B199798 Model No: 1A30311DD

As you appear to have the manual, you will have the Wiring diagrams.

Parts and Service Bulletin list for s/n 1B199798:

Search Results - Crowley Marine

Gerry

 

[wired247]

Re: 2005 Mercury 4s EFI tiller bad plug on Engine Harness Connection

The 8 pin wiring harnesses are the same no matter what the HP or year. You have to be able to plug it in to an 8 pin wiring control set after all.

 

[rhalter]

Re: 2005 Mercury 4s EFI tiller bad plug on Engine Harness Connection

I called Mercury today. Maybe I should have mentioned the motor is a tiller. Here is what they told me:

1 - Black yellow
2 - Purple
3 - Tan with blue stripe
4 - Black
5 - Grey
6 - empty
7 - Yellow red
8 - red purple

Now I'm puzzled. The bad terminal doesn't even have a wire in it?

 

[rhalter]

Re: 2005 Mercury 4s EFI tiller bad plug on Engine Harness Connection

looks like the tiller handle connection #6 is the yellow with black stripe wire and the engine harness connection #6 is empty. 37 is the engine harness connection, 36 is the tiller handle connection.

 

[wired247]

Re: 2005 Mercury 4s EFI tiller bad plug on Engine Harness Connection

Do you have a wire going into that connection point on the plug. I changed mine from a tiller jet motor to external controls and used the same plug . I suppose Merc could have done it differently just to be different on the smaller motors.

 

[rhalter]

Re: 2005 Mercury 4s EFI tiller bad plug on Engine Harness Connection

On the plug end which is coming from the tiller handle (male connection) is a yellow wire with black tracer. On the engine harness receptacle end (female connection) there is no wire on the blown out #6 receptacle.

 

[rhalter]

Re: 2005 Mercury 4s EFI tiller bad plug on Engine Harness Connection

Spoke with somebody from the place I bought the boat from today and they said to start with the lanyard stop switch and push button stop switch. I often raise and lower the tiller handle. I wonder if the wires got pinched where the pivot point is? Any thoughts?

To start with again the initial problem was the 20 amp main relay fuse in the fuse holder blowing and I had a burned out receptacle in the engine harness connection however there's no wire in the terminal that's blown out.

 

[AChotrod]

Re: 2005 Mercury 4s EFI tiller bad plug on Engine Harness Connection

That connection looks fried all over the inside. I would replace the entire harness.