Voltage dropping and no power to accessories

[justmike65]

I have a 1994 Wellcraft 18 Fish and none of my accessories are working. I posted about it earlier because I was looking for a color code chart, but now I know much more about the problem.

I am taking voltage readings from the positive and negative buses.

The voltage drops from 12 to 1, 2 or 0 when the fuse is in place for the radio and GPS/depth/fish finder. They are on the same circuit.

When the fuse is out of place, the voltage reads 12 but none of the accessories work...

Accessory list:

• Courtesy lights
• Bilge pump
• Navigation lights
• GPS/Stereo
• one more thing that I forget... I will update when I know what it is

There is no problem with the engine electrical or the trim. All gauges work on instrument panel.

Any advice is greatly appreciated!

 

[bruceb58]

You have a highly resistive connection between the battery and your fuse box so that when a load is put on, your voltage drops. Get a long test lead and put it on the positive post of your battery. On the other side put the lead on the positive post of the fuse panel and apply the load. Should be 0V. Do the same on the negative side. The side that has the large number of volts is the side you need to investigate.

 

[justmike65]

You have a highly resistive connection between the battery and your fuse box so that when a load is put on, your voltage drops. Get a long test lead and put it on the positive post of your battery. On the other side put the lead on the positive post of the fuse panel and apply the load. Should be 0V. Do the same on the negative side. The side that has the large number of volts is the side you need to investigate.

I will try that. I just talked to someone who said that is "very clever". Thanks!

 

[bruceb58]

I will try that. I just talked to someone who said that is "very clever". Thanks!

We do that all the time to find where voltage drops exist. Once you find the leg that has the large voltage drop, keep the lead on the battery post for the side that has the drop and work your way back to the battery on that leg.

 

[justmike65]

No Title

We do that all the time to find where voltage drops exist. Once you find the leg that has the large voltage drop, keep the lead on the battery post for the side that has the drop and work your way back to the battery on that leg.

Does this qualify as resistive?

 

[bruceb58]

Does this qualify as resistive?

Maybe!

So what and where is that from?

 

[justmike65]

Maybe!

So what and where is that from?

Did what you said. Positive side showed 12v. Bought a $1 mirror at Dollar Tree so I could see below deck and saw electrical tape on a group of wires. Took it off and saw that. It was on the 12v side between the battery and the fuse block, in the most inconvenient place.

 

[Fed]

Were you able to determine how the connection was made in the failed joint Mike?

Solder Vs Crimp Vs Who Knows What?

Inquiring minds you know.

Good picture to keep on file for those who say, "my wiring looks fine".

 

[mjf55]

Does this qualify as resistive?

that made me laugh out loud. nice picture.