View Full Version : Disconnected wires behind the dash

04-24-2014, 10:40 PM
Hi, last summer I purchased a 1992 Prostar 205 as some what of a project boat. I,m the 3rd owner and don't know much of the history behind it. It has approx 850 hrs and seems to be in OK shape. The engine starts and runs fine. The boat performs well for it's age.

The fuel gauge and oil pressure gauge does not work. The previous owner said the oil sending unit needed to be replaced. I replaced it but it did't fix the problem. I then went behind the dash and found two wires that were disconnected and an electronic board that has two male plugs with nothing connected to them.

Here is a pic of the electronic board. Does anyone know what is suppose to be connected to it. The male connectors are marked "+" and "output". There is a single purple wire coming from the Temp gauge that is disconnected and two purple wires connected together with a female plug that is disconnected. One wire comes from the volt meter and the other comes from the Temp gauge. I'll try to post a pic of those too.

Does anyone know how these wire should be connected?

Thanks for your help

04-24-2014, 10:42 PM
Here is a pic of the two purple wires. They come from the temp gauge and the volt meter.

Table Rocker
04-24-2014, 11:00 PM
I'm guessing the purple female with two wires goes to the oil pressure gauge and the single goes to the buzzer board (+) terminal. Just my guess though.

The purple wires should be (+) with 12+ volts with the key on. Nothing with the key off.

04-25-2014, 07:39 AM
I'm not sure but I guess, from what the PO said to you, when the oil sending unit failed, rather then replace it he disconnected the gauge and buzzer?

04-25-2014, 07:51 AM
Again guessing but I'm thinking since the board has a speaker on it that it is an alarm device hence the input posts. If I'm looking at this correctly I'm seeing a positive, negative, two inputs and an output post on the board. It would appear that the positive post is disconnect which would render the device inactive. The two square components at the top of the board appear to be "pots" which would be used to adjust set levels for the alarm. My next guess is that it was disconnected because it had failed and the alarm kept going off. I'm thinking the single wire will be 12 volts with the key on and it will go to the positive terminal. The two wires connected together will go to the output post and will send the signal to your gauges. This would explain your non functional gauges.

Time to plug them in and see what happens. My guess again is that the alarm will go off at which point you could experiment with the trimmer pots to see if you can adjust the set points, that is if the operating conditions of the engine are within specification.

Again this is my best guess based on what I can see. Only someone with the same circuit could tell you for sure.

04-27-2014, 10:34 PM
I have my dash out. I will check mine tomorrow when I get to the shop.