Although not particularly high in terms of total maintenance costs, one of the key reasons for electrical problems being a top concern is because of the fickle nature of electrical connections and components.

Because drivers can spot a wearing tire or monitor engine oil, protocol is in place to address these issues. However, electrical systems can work fine one day and be dead the next.

Among the few electrical components with any substantial warranty, batteries often carry a warranty rating of anywhere from 24 to 72 months. Yet, the warranty period only provides a guess as to how long the battery will last. A 48-month battery could expire in 36 months or provide reliable service beyond 60 months.

Although there might be some warranty compensation for a battery that dies out on the road after 37 months, that is of little comfort when that cargo containing thousands of dollars worth of dairy products is spoiling in the back of the truck. Fortunately, batteries can be tested to provide some indication of remaining life span.

“Leading proactively, not reacting to breakdowns” is a motto to remember. This means that for the electrical system, maintenance must be highly proactive and focused on preventing downtime.

Even fleets based in warm climates still are likely to encounter more road spray during the winter than during the rest of the year. For trucks in cold-weather locations, road spray includes a significant concentration of salt and other road de-icing compounds.

Given the location of battery boxes on most trucks, it’s highly likely that some of this spray will end up inside the battery box, where it could settle on top of the battery/batteries, forming a thin, damp film. This film actually is electrically conductive and, if left long enough, will discharge an otherwise healthy battery in a truck.

Although it’s also a good practice during mid-winter maintenance visits, a mandatory part of a trucks’ spring cleaning maintenance visit should be opening the battery box and performing a thorough pressure washing of the batteries, the battery box and all components inside. Additionally, all battery cables should be disconnected and inspected for physical integrity, with all connecting surfaces cleaned down to bare metal.

As long as the battery cables are disconnected, it’s also a perfect time to load test each battery. A load-testing machine is expensive, but not compared with numerous unplanned road service calls, so it can a worthy investment for a fleet with as few as 10-12 trucks. Although a load test won’t provide an exact “dead by” date, it will allow plenty of planning time.

Before reconnecting the cables, take advantage of the extra room to inspect all battery bracket hardware. Vibration can be a mortal enemy to most truck batteries, and, after a winter’s worth of potholes, be sure to check that all batteries still are securely mounted.

Once the batteries are secure and the cables are reconnected, it can be beneficial to coat the terminals with a corrosion protectant, such as dielectric grease. However, some consumer-grade “sticky” sprays might work their way into the connection and cause electrical problems, so it is best to use a commercial-grade product.

The next most winter-vulnerable component in a truck’s electrical system is the starter. At a bare minimum, all electrical cables and terminals should be disconnected, inspected and cleaned. If at all possible, the starter should be removed from the truck and given a thorough cleaning and inspection before re-installation.

Nothing short of a complete overhaul of the starter can provide much assurance of its reliability, and even that only comes with a short guarantee. Like many other electrical components, an ounce of prevention, in the form of an in-shop cleaning and inspection, is worth several pounds of a roadside cure.

Perhaps the most fickle of electrical system components is a truck’s alternator. Beyond ensuring the integrity of cables, connections, mounting brackets and drive pulleys, minimal maintenance is needed or possible because of the alternator’s much more protected location, compared with the batteries and starter.

If the truck is having starting and charging problems, and the batteries and starter have passed testing, the alternator can be checked for performing at its rated output. But with partial failures being extremely rare, alternator testing usually comes down to determining whether it’s working or dead.