Gauges not working

[Islandlure]

Hi guys, I just bought a 95 Roberts flats boat with a 85 Johnson 70HP. Only problem I can see after owning it for a week is that none of the gauges work (tach, speed, battery, fuel, temp). All gauges light up but have no readout. I took the center console off and checked the wiring and it all looks fine, all connections look clean and are in heat shrink terminals. Just wanted to get someone else's opinion before I start cutting and re-wiring everything. I just find it odd that all gauges would be bad but still all of them light up. So if you have any other ideas I would appreciate it. I hope I posted this in the right place but I am thinking that the gauges would be related to the motor or the control box. Thanks in advance!

 

[Barnacle_Bill]

Re: Gauges not working

Check for 12V going to the gauges. Lights are on a seperate circuit.

 

[Islandlure]

Re: Gauges not working

Yep, I had checked the power and ground and they are getting 12V. I think I am going to have to pull the console out and all the gauges to figure this out. I guess that give me something to do next weekend.

 

[tashasdaddy]

Re: Gauges not working

imho, the best thing that ever happened to that boat. Gauges are aggravating, and unnecessary. them motor has built in warning systems. i hate gauges.

 

[Islandlure]

Re: Gauges not working

Yea, I hate most electrical items in boats, but my main concern is the fuel gauge, especially being a new boat to me. I don't really care to have to other gauges working, maybe a tach would be nice to have but other that I need nothing else.

 

[tashasdaddy]

Re: Gauges not working

it sounds like you do not have power to the guage, it should be totally independent of any of the motor wiring. moving to electrical.

 

[Islandlure]

Re: Gauges not working

Thanks, I should have put it there but I had already posted and didn't want to double post. I appreciate the help!

 

[Silvertip]

Re: Gauges not working

Cutting out wiring to get gauges working is the last thing to do. Find out "why" they are not working. Here is a generic diagram of a console full of gauges and switches. Note that all of the +12 volt, ground, and light connections are daisy chained from one gauge to the next. If the first gauge in the string is missing either 12 volts or ground, the others will be dead as well. The gauges are powered by +12 volts from the "A" terminal on the ignition switch.

 

[Islandlure]

Re: Gauges not working

Awesome Silvertip! Ok, this makes sense I bet something is up with 12V at the first gauge. I can't see up in there all the well but from feeling around they felt like they were daisy chained. I will have to pull the console completely out to be able to get to them to accurately test them all but this diagram already helped! Thanks so much!

 

[coastalcruiser]

Re: Gauges not working

grab a little test light, they are great, your guage lights are hooked to your running lights switch and the guages are powered by the key also checking with that test light, clip it to the ground on the guages to double check that is not the problem.

 

[JoeW80]

Re: Gauges not working

Great diagram Silvertip...

I just got my first boat and the fuel guage does not work.. I haven't really troubleshot it yet but I did notice that the +12V from the ignition is hooked up to both +12V locations shown in your diagram. So my question is what is the +12V from Nav/Anchor switch? I'm guessing that it is for the gauge backlight and it is meant to turn on when you turn on your lights?

If that's the purpose, then since my guages all have the +12V ignition wire connected to that location, the guage backlights will always be on. I know this isn't ideal but is it worth re-wiring?

 

[Silvertip]

Re: Gauges not working

Electricity in a boat is a precious item, why have lights on when they are not needed. Wire them to the NAV side of the switch. That way they won't be on when at anchor and they will be on when underway (NAV setting). This also lets you know that your NAV lights aren't on when they should be since you won't be able to see the gauges at night. Ain't "logic" a great thing!!!

 

[Searay19]

Re: Gauges not working

Silver tip awesome diagram.


I had the same problem, purchased a boat and pow about 3 guages went out.

I used my volt meter to check power, Once i seen i had power, I went to harbor freight say for the amp side. And bought a guage 3-6 bucks, Hooked i up to see if it worked, As it did i new that just the guage went out.

Everything goes at one point just sometimes at the wrong time, Try that. Let me known if you need any more help

 

[NoGin]

Re: Gauges not working

Sorry to hi-jack your thread but I have a quick question pertaining to gauges and the engine. Do all the gauges need to be hooked up for the motor to run?

Trim?
Tach?
Volt?
Fuel?
Oil?
Temp?

 

[Buoybuoy]

Re: Gauges not working

Silvertip,

I know little to nothing about electric and had three of my four gauges not working. I just fixed all of the gaugues myself thanks to your schematic.
Awesome!!!

Thanks again.

 

[Silvertip]

Re: Gauges not working

Since the gauges all light up, that says they also have a good ground. But since none of them work, that says you DO NOT have +12 volts going to them. Check the "Generic boat wiring diagram" sticky at the top of this forum. You will see that +12 volts and ground are daisy chained from one gauge to the next. If the first one in the string is not getting +12 volts when the key is on, then none of the others will either. The only gauges that don't have an electrical sender is the voltmeter, speedometer, and water pressure (if you have one). If your voltmeter does not work, then 12 volts is definitely missing.