Wiring diagram for Merc 454?

[bellmd]

I have a 1997 Emerald Reunion 26' with Merc 454 (engine code OK196XXX) and Bravo III (model OK146XXX). Seems that manufacturer is no longer around and I don't have any manuals. Like anything 10 yrs old it's starting to need some love and I wanted to try and do the simple stuff myself.

First objective: My voltmeter isn't working and I was wondering if there were any wiring diagrams that might get me close? Sorry for the novice/newbie level questions, thanks in advance for any assistance!

 

[Silvertip]

Re: Wiring diagram for Merc 454?

First, the wiring diagram for the boat is totally separate from the wiring diagram for the engine. Next, the voltmeter only has three wires on it. Ground, light, and +12V. The meter should see +12V with the key in the RUN position. If it has +12V and a good ground, then the gauge is bad. If you don't measure +12V at the gauge check all of the 12V and ground connections on all of the gauges as well as the ground and +12V connections at the source. You can simply follow the wires to do that. Go to the Electrical forum. At the very top of the forum is a post titled "Generic Boat Wiring Diagram by Silvertip". It should help you locate the problem. Wire colors will probably not help you except for +12V (red) and ground (black).

 

[bellmd]

Re: Wiring diagram for Merc 454?

Thanks for the quick reply and info. I'll check voltage at the gauge first and see where that takes me.

 

[bellmd]

Re: Wiring diagram for Merc 454?

Ok, I've got got 12V at the voltmeter when the ignition is turned to "ON". Light doesn't work on it either but have 4V to the lights wiring. Guess I need to find a new voltmeter and see if that fixes the prob.

My gauges are black faced with only a red "Q" for logo, anyone know what brand that might be?

Thanks again for the help!

 

[Bondo]

Re: Wiring diagram for Merc 454?

Ok, I've got got 12V at the voltmeter when the ignition is turned to "ON". Light doesn't work on it either but have 4V to the lights wiring. Guess I need to find a new voltmeter and see if that fixes the prob.

Ayuh,......

That sounds like a Bad Ground, not a Bad Gauge....

 

[bellmd]

Re: Wiring diagram for Merc 454?

Ayuh,......

That sounds like a Bad Ground, not a Bad Gauge....

I put the black lead from the multimeter to the post on the voltmeter where the ground wire was connected, the positive lead from the multimeter to the positive post on the voltmeter so I thought when the multimeter read "12.6V" that meant I had a good ground and postive connections? Have I missed something obvious?

EDIT: Just removed the ground wire, cleaned it up a bit and reattached. Now I have a lighted gauge but still no needle movement when switching the ignition to the "ON" position. Thanks for the help, sorry I'm slow on the uptake!