I would track down what has been added to the fuse block on what I call "taps" (the 1/4" male terminals on the fuse block for adding accessories which allow for things to be on all the time, only when the ignition switch is in the accessory or run position, or when the ignition switch is in the run and crank position, as well as then allowing additional lighting to be added and controlled by the headlight switch to include dimming).
These "taps" are labeled BAT for a source of constant power, and then one labeled ACC which only has power when the key is in the accessory or run position, then one labeled IGN that has power when the key is in the run and crank position, and then the last is a tap labeled LPS which is a variable 0-12V output controlled by the headlight switch.
These "taps" are protected by neighboring fuses to where if an overload or short occurs then the proper fuse will blow.
These "taps" are also protected by different size fuses so this must be taken into account when doing things. You NEVER want to use for example the ACC "tap" terminal pictured in your photo being protected with a 10A fuse on a wire smaller than 14 gauge (for some reference:
12 Volt Automotive Wire - American Made - WiringProducts. Ltd. ). These numbers int he chart are for reference and it's not written in stone, if you stay close to those recommendations, you should be fine.If you are going to error,go to the larger gauge wire.
Remember that the fuse is to protect the wire AFTER it.
IF you find yourself finding out what is plugged into the fuse blocks IGN tap, and it is something you still need to retain, then you need to gather some parts so what you are adding is more of a plug and play type of setup.
The ignition "tap" is a 1/4" male terminal and one can use a 1/4" female terminal to make a connection to it. You can then unplug what is already there on the "tap" and then with some wire, basically make up a "Y" connection. Take some 14 gauge wire and on a stripped end,crimp on a fully insulated 1/4" female terminal. Now go backon this wire maybe 2" or so and cut the wire. Now strip both ends of those wires, twist them together and now crimp on a fully insulated 1/4" male terminal. The long side of the wire will go to some device and then the dangling fully insulated 1/4" male terminal then also a second thing to be plugged into it using a fully insulated 1/4" female terminal. You can do this not once, but twice, three times, four times or more BUT remember you need to know what the total amp draw will be so that the fuse protecting the 'tap" in the fuse block is not overloaded.
This is a factory setup to add a cruise control using the "tap" and then the unused and can be used for yet another added item.
Here is the one for a factory rear defroster:
Also notice too on the "taps" that they are keyed to where an assembly line person or a person adding a factory designed part cannot plug it into the wrong spot. They wanted to make it idiot proof.
Jim
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