Jet Ski Electrical System and Fuses Explained [Video]

A Jet ski’s electrical system features many key parts including a battery, a stator, a starter motor and relay, wire harnesses, and an electric box. The latter typically houses the fuse panel and the ECU, which is considered the main computer on the jet ski.

If you want to find out more about a jet ski’s electrical system and its fuses, this post is for you.

We at JetDrift have compiled all you need to know under one roof!

What are the Electrical Components of a Jet Ski?

Just like any other powersport vehicle, jet skis have a complete electrical system. The electrical components of a jet ski may vary by model, but they typically include:

• Stator
• Battery
• CDI
• Starter relay
• Starter motor
• Wire harnesses
• Electrical box
• Fuses
• ECU and /or MPEM

Electrical energy is generated by the stator, which is a generator driven by the engine crankshaft. This energy is used for the electrical system on the jet ski and to charge its battery.

Vintage jet skis only featured a very simple electrical system featuring a stator, a battery, wire harnesses, and an “electrical box.”The latter was an enclosed plastic box that housed the fuse panel, the main control unit (MPEM or ECU), and a bunch of wires.

Certain models like early Sea-Doos featured an additional, “rear electric box,” which was also referred to as the starter solenoid box. As the name suggests, this box enclosed the starter solenoid and was planted near the starter motor.

On vintage jet skis, the battery had to only feed a few systems including the ignition, starter motor, and dashboard.

But over the years jet skis have become more and more complex, as have their electrical systems.

The first fuel-injected 2-stroke jet skis hit the market in the ‘90s when Sea-Doo also introduced its special DESS key security system.

Although these innovative features were useful for riders, they also added a lot of complexity to the electrical system.

To manage these new components, the manufacturer started to use a more advanced “computer” in their skis, known as Engine Control Unit (ECU).

This unit was intended to control many different functions, including:

• Start/stop function
• Distributing information
• Interpreting information
• Timer
• Ignition timing curve
• Engine rev limiter
• Gauges’ current supply

Since then, on some skis, the fuse panel and the ECU are manufactured as separate components, while on others these two have been merged into one unit.

Besides these major elements, various electric gadgets have become more prevalent on jet skis. These include electric brake and reverse systems, monitoring and onboard diagnostic systems, displays, GPS, fish finders, and even sound systems.

Therefore, it’s no surprise that modern jet skis feature a pretty complex electrical system!

Do Jet Skis Have Fuses?

Like any other vessel and vehicle, jet skis also feature fuses which are designed to protect the wiring and the electrical components from short circuits or overloads.

The general rule is that a modern jet ski has about 10-15 fuses depending on the make and model. Jet skis use various fuses, including:

• Battery fuse: 30 A
• Main fuse: 20 A
• Main relay drive fuse: 10 A
• Electronic throttle valve fuse: 10 A
• Security system fuse: 3 A

(This list is for informational purposes only! The exact fuses and their amperage may vary depending on the model and the year.)

Where are the Fuses on a Jet Ski?

The fuses on a jet ski are located in a plastic box, known as a fuse box or electrical box. This sealed grey or black plastic box is mounted inside the engine compartment usually near the battery or hidden somewhere under the top deck.

Inside the box, you can find the fuses in separate in-line fuse holders or a fuse panel.

Conclusion

Like any other vehicle and vessel, jet skis also feature a complete electrical system with a battery, stator, starter motor with a solenoid, wire harnesses, and an electrical box.

Over the years this system has become more and more complex and today it features a “mini-computer.” This unit is considered the brain of the jet ski and is called the Engine Control Unit (ECU).

Besides the engine and its systems, the electrical system controls and feeds many features and accessories on the jet ski, including the reverse system, dashboard, and sound system.