A Guide to Your Acura's Electrical System

The Most Important Parts of Your Acura's Electrical System

Generally speaking, Acuras boast the reliability of Hondas while spoiling owners with creature comforts. That having been said, an Acura still lives and dies by its electrical system. To keep your Acura in fine form, you should know a little about these electrical parts.


When you break it down, your Acura's battery is just a big store of energy and very little else. Its primary purpose is to provide an initial jolt of current to the starter to fire up your engine. It also keeps your clock and radio settings current when your Acura is off.

Even the best batteries break down eventually. Regardless of manufacturer guarantees, a good battery really only lasts three to five years at best. If you live in a particularly cold climate, your battery can die in as little as two years. If you have an average sedan or coupe, a decent battery is about $110 to $120.

There are a few steps that you can take to extend battery life. Use battery insulation to protect your hardware from temperature swings. Regularly clean corrosion from the terminals to ensure proper current flow. Finally, use a charger to keep your battery topped off if your vehicle is going to be garaged for long periods.


It's not an exaggeration to say that the alternator is the most important part of your Acura's electrical system. It converts the kinetic energy of a rotating crankshaft into the electrical energy required to power your spark plugs, headlights and power windows. It also recharges your battery so that your Acura starts reliably.

Over time, the internal components that allow an alternator to generate power such as the bearings and diodes eventually break down. You can tell that your alternator is close to death if the battery light on your instrument cluster suddenly appears while driving. Other common signs of imminent alternator failure include flickering headlights and spotty radio reception.

Acura drivers can prolong alternator life by reducing the load on the unit. Switching to LED headlights, dome lights and turn signals is a step in the right direction. Installing an alternator with a higher amp rating is another way to go. Test your alternator's output once a year to look for signs of impending death.


Your Acura's starter is responsible for turning the engine over when you insert your key in the ignition. By closing the ignition circuit, you're allowing current to flow from the battery to the starter solenoid. When that happens, a gear in the starter forcefully engages the engine's flywheel and turns the crankshaft.

As a brushed DC motor, a starter is only good for a certain number of uses. Eventually, internal components break down and the unit as a whole must be replaced. Moisture and environmental contaminants like dust and debris will also shorten a starter's life. If your starter makes a clicking noise, it's going to die shortly.

If you want your starter to last longer, reducing the number of times that you use it is a good idea. You'll find that Acuras with a lot of highway miles don't need a starter replacement for up to 200,000 miles or more. Garage your Acura whenever possible to protect the starter from moisture damage.


Your Acura's fuses are critical components that ensure the health of your electrical system. They protect the wiring from damage in case a device like a radio or an AC controller draws a large amount of current. They're really just pieces of metal that melt if they're hit with too much power.

Every Acura on the road has at least two fuse boxes. One is located in the engine bay and protects circuits for things like ECUs and radiator fans. The other fuse box is usually located under the steering wheel and governs circuits dedicated to passenger area devices like dome lights, power windows and power seats.

There's not really a lot that you can do to protect your fuses from harm. They're incredibly cheap and inherently disposable anyway. If you blow a fuse, you simply pull out the old unit and install a new one. Take care to install a fuse rated for the appropriate amperage for any given circuit.

Ignition Switches

While most drivers deal with ignition switches every day, few understand how they actually work. When you start your car, you're using your key to complete a circuit and allow current to flow from the battery to the starter. Ignition switches also allow power to reach accessories like radios and headlights.

Ignition switches usually fail when the electrical contacts within them become worn or damaged to the point where they can't maintain a steady electrical current. If your ignition is about to fail, you'll notice a few classic signs including flickering instrument panel lights, unexpected stalls while driving and an absence of noise from the starter.

The best way to make your ignition last longer is to avoid physically damaging it. Don't attach heavy accessories to your keychain as the added weight can do a number on your ignition switch. If you do need to replace an ignition switch, you'll have to disconnect the steering column to swap out the hardware.

Instrument Clusters

Nowadays, Acura instrument clusters are highly sophisticated electrical components that provide drivers with a wealth of accurate information. Behind the hardened plastic facade and trim, there's a circuit board that takes input from various sensors and manipulates gauges via stepper motors. Troubleshooting instrument cluster problems is rarely an easy task.

Instrument clusters generally fail as a result of manufacturing defects. If you get a decent cluster that doesn't exhibit problems early on, it'll probably last for the life of the vehicle. Even a single sub-par solder point or stepper motor can cause the entire unit to fail in ways that are hard to diagnose.

As a sensitive piece of electrical gear, an instrument cluster can be easily damaged by environmental threats like moisture and dust. Use your AC system to maintain a favorable climate inside your Acura whenever possible. The nice thing about instrument clusters is that they're easy to replace by simply loosening a few screws and removing the power cable.

Engine Control Units

The ECU acts as the brain of an Acura by controlling nearly every aspect of its performance. Its most important function is monitoring and adjusting various engine settings like idle speed, valve timing and the air/fuel ratio. Modern ECUs make your Acura more powerful, efficient and reliable.

A quality ECU can last for the life of the vehicle or even longer if it's manufactured properly. Like any device that contains a circuit board, heat and moisture are the biggest threats to an ECU. Diagnosing a faulty ECU is a tricky proposition. If you notice a slew of disparate engine hiccups, have a certified mechanic look at your ECU.

Aside from maintaining a clean, dry environment within your Acura, there's not much that you can do to make your ECU last longer. It's always a good idea to keep an eye out for ECU software upgrades issued by Acura for your specific model. Have a professional at a dealership update your ECU if necessary.

Making Your Acura the Best That It Can Be

Ultimately, your Acura's electrical system requires high-quality OEM replacement parts to work properly. At AcuraOEMParts.com, we've been stocking and shipping the finest genuine Acura parts longer than any other online vendor. When your Acura's electrical system is on the fritz, our expansive inventory is the solution to your problems.