COMMON FAULTS

There are a number of common faults that can plague your electrics, the first and most common being water damaged to the electrical connections. Take a look at the damaged vehicle auction page and there will be a flood of immaculate 4WDs up for auction shortly after a region has seen substantial land flooding. These 4WDs might nothing wrong with them when you buy them, but not long after they have dried out is when a plague of electrical issues start. Generally the connects start corroding, reducing the conductivity of the connection as resistance builds. Too much resistance and the voltage drop alone can cause issues.

Good conductivity is the secret to good electrics and good surface to surface contact, it as well as good wire termination perform better than those that do not. As off road enthusiasts, many of this electrical connection will be subject to dirt, water and shock loads. Scotch locks are a big NO when it comes to anything automotive. They make easy temporary repairs when you are miles from anywhere and you don’t have a soldering iron or crimples tool in with you, but never this use for long term installation. They can lose contact when disturbed or shaken, the contact bar inside is reliant on making contact with the wires after the plastic sleeve has been penetrated, and they can cause permanent damage if they arc out or penetrate too deeply.

Over loading a circuit or the wiring itself is another common cause. From basic electrical principles power equal current multiplied by volt P multiplied by V battery voltage changes as the voltage drops so if for example you had a 100w load it would consume 7.8 amps at 12 .8 volts. Drop the voltage to 12 volts and the current rises to 8.4 amps (l_ P divided by V). Although this might not seem like much on paper, extra current will generate extra heat, which in turn lowers resistance and causes current to increase. What this mean is that a circuit that is installed to carry 10 amps may be over loaded as voltage and current flow increases. The outcome of this is that over a period of time the cabling itself can be damaged.

Series and parallel circuits are another cause of faults normally circuit done DIY parallel circuits have each electrical item branching off a common supply, while item in a series circuit follow a line, being fed from the voltage that has passed through the first item. As the voltage passed though each item a voltage drop occurs, and subsequent item down the line may not have enough.