Electrical questions

[gunlocators]

Ok I swapped a 88 48HP Johnson on my pontoon and replaced witha 78 85HP Evinrude. The throttle / shift linkages matched up and local boat guy said wairing harness was the same. It did have same plug pin at motor. So everything seems good Tach, Instrument back lights ect seemed to work except. I noticed the voltage gauge was reading 12v with key off. So i took test light at harness below instrument panel and it seems I only have 12v constant going to the gauges and in the wiring harness I do not have 12v wire with key in on position? Any ideas I dont understand why there would not be a 12v ignition wire. Getting dark here so plan to look at it again in the morning. Should i try to pop the control box open thats where the key is and find 12v with key on and pull a new wire to instrument cluster.

 

[tashasdaddy]

Re: Electrical questions

i would just cut the darn wire, i hate gauges. as it is you have a constant drain on the battery when the key is off.

 

[kenmyfam]

Re: Electrical questions

OK, I am a little confused. (and I do confuse easily)
Are you saying that the only issue is the constant 12 volt feed to the instruments whether the key is on or off ???.....or that the key switch is not working correctly ?

 

[ezeke]

Re: Electrical questions

Trace the wires in the large red plug - that's key. Click the thumbnail.

 

[gunlocators]

Re: Electrical questions

OK, I am a little confused. (and I do confuse easily)
Are you saying that the only issue is the constant 12 volt feed to the instruments whether the key is on or off ???.....or that the key switch is not working correctly ?

I am saying I tested the harness at console and nothing has a 12v with key in on position but I do have constant 12v with key on or off and thats going to the gauges

 

[gunlocators]

Re: Electrical questions

Trace the wires in the large red plug - that's key. Click the thumbnail.

Is this schematic good for both a 78 model and a 88 model I am using the 88 model harness that was on there for the original 48hp Johnson however I replaced the motor with a 78 85hp Evinrude

 

[ezeke]

Re: Electrical questions

Print Bill Kelly's diagram so you can follow the wiring: http://www.maxrules.com/graphics/omc_pics/REMCONTBOX.jpg

As you see from the circle diagrams, nothing should be hot when the key is turned to off, and anything connected to the "A" post is hot when the key is in the run or start position.

If the gauges are connected to the "A" post, and are hot with the ignition off, then you either have a bad switch or the wiring is wrong.

 

[gunlocators]

Re: Electrical questions

Ok apparently someone has rewired this before.

Ok everything checks out with the Big Red Plug upon further invetigation I got uner the pontoon and looks as original wireing harness going up to the helm was cut and spliced into. I found the following tracing from helm back. There was only 8 wires 4 of which are speaker wires other four wires has 2 large red and black wires about 10ga going straight to the batterys + and - the other 2 wires smaller red and black go to gas tanks sending unit.

So there is NO acc or (+) while key on wire going to the helm. Whats the best way to resolve. Run a acc wire from red connector plug back at motor or tap into the control box and try to tap in from there and run a wire.

 

[gunlocators]

Re: Electrical questions

Also my buddy that went with me and we test drove the boat reminded me no guages were working until we flipped some switches it loos as if they used a mater switch to turn everything on to bypass a key on (+) . I perfer not to have a master switch incase i forgot about it then i would drain my battery so I perfer to have a key on (+) going to the gauges

 

[ezeke]

Re: Electrical questions

You should have another circuit from the battery for accessories, but the gauges are usually wired to the ignition switch, with the gauge lights working off a different switch.

There are some boat wiring diagrams in the other forums, including this one by Silvertip: http://forums.iboats.com/showpost.php?p=1259309&postcount=1