Corrosion is very damaging to vehicle lighting and wiring because it will compromise the electrical system by causing a larger voltage drop across the corroded wire, says Adam Bean, new product development manager for Phillips Industries, a leading supplier, innovator and manufacturer of advanced electrical and air brake interface equipment for the commercial vehicle industry.
Anywhere there is an exposed connection allows for corrosion, he says. For example, connectors underneath the trailer are exposed to water splash back from the tires. The seven-way socket/plug is particularly susceptible because it is plugged in and out, allowing for debris to get in and start eating away at the terminals from the inside. Plus, this connection/disconnection gets cycled regularly, allowing for the spreading of pins.
Corrosion is particularly detrimental to LED systems because it attacks a lamp's most venerable point - its electrical connections, notes John Grote, vice president sales and marketing for Grote Industries, a leading manufacturer and marketer of vehicle lighting and safety systems. Lamps that are not secure and that have not been properly maintained can be "killed" long before they serve their life expectancy of 10-plus years.
Today's LEDs are often designed to uses dielectric grease and modular connection designs to resist moisture at the connection point, but still must be inspected regularly and the grease replaced when needed.
Corrosion is most often caused by moisture intrusion within a vehicle's electrical and power delivery system, he explains. "An electrical and wiring system can be compromised via leaking lamp connections, cracked lamp lenses, wire and cable abrasion, grit and sand damage, extreme temperature fluctuations, extensive flexing and exposure to moving parts.
"The chemicals used to treat the roads can accumulate on the equipment via road spray and will eventually ‘eat' away the components on a piece of equipment, including the electrical system. Chemical-based corrosion is prevalent on trailers, as the harness system is typically exposed to the elements."
In an effort to prevent corrosion, Grote says fleets and OEMs are employing systems that can fight off corrosion, and are using connections that are more secure, and thus require less maintenance, reducing the chances of having to unplug a connection to diagnose a problem. They are also providing sealed solutions, die-electric greasing anything exposed that can't be sealed and using water-tight methodologies, molding over connections to protect the wires/pins from wicking water into the harnesses, adds Phillips Industries' Bean.
What's more, many fleets and OEMs are moving to modular electrical systems. These can expand easily through standardized wiring segments with connectors that snap together and are designed with reservoirs for dielectric grease to provide enhanced moisture barriers.
New modular nose boxes are also becoming popular and feature consolidated, multi-pin connectors and water-resistant modular plugs, Grote adds. These nose boxes incorporate mounting systems with gaskets that prevent the migration of moisture.
The best way to prevent corrosion on a vehicle is to be proactive. Don't expect; inspect. Regular inspection of the equipment and proper preventative maintenance measures are not only more effective than corrective maintenance, they are usually less expensive and easier. The objective needs to be to attack corrosion before it becomes a serious problem.
In addition, Grote recommends a regular and thorough examination of the vehicle's electrical system and lighting. Light fixtures, wires and cables should be inspected for cracks, corrosion, excessive wear and punctures and should be replaced immediately as issues are identified. Even small surface cracks and holes in a wire or cable can cause moisture to wick into the system.
Foam/protect any exposed loose wires, says Bean of Phillips Industries. Loose wires that have the ability to wiggle around and chafe will eventually lead to a breach of the system, allowing dead shorts and corrosion to start. Cable ties, split loom, die-electric grease should be used where ever necessary. Coat or die-electric grease anything that will be exposed.