Jeep Wrangler 2018-2026 Owners Manual / SERVICING AND MAINTENANCE / ENGINE COMPARTMENT / Maintenance-Free Battery

Jeep Wrangler: ENGINE COMPARTMENT / Maintenance-Free Battery

Your vehicle is equipped with a maintenance-free battery. You will never have to add water, and periodic maintenance is not required.

WARNING!

Battery fluid is a corrosive acid solution and can burn or even blind you. Do not allow battery fluid to contact your eyes, skin, or clothing. Do not lean over a battery when attaching clamps. If acid splashes in eyes or on skin, flush the area immediately with large amounts of water.
Battery gas is flammable and explosive. Keep flame or sparks away from the battery. Do not use a booster battery or any other booster source with an output greater than 12 Volts. Do not allow cable clamps to touch each other.
Battery posts, terminals, and related accessories contain lead and lead compounds. Wash hands after handling.
Vehicles with the Stop/Start system will be equipped with two batteries. Both the main and the supplemental batteries must be disconnected to completely de-energize the 12 Volt electrical system.
Serious injury or death could result if you do not disconnect both batteries. To learn how to properly disconnect, see an authorized dealer.

CAUTION!

It is essential when replacing the cables on the battery that the positive cable is attached to the positive post and the negative cable is attached to the negative post. Battery posts are marked positive (+) and negative (-) and are identified on the battery case. Cable clamps should be tight on the terminal posts and free of corrosion.
If a “fast charger” is used while the battery is in the vehicle, disconnect both vehicle battery cables before connecting the charger to the battery. Do not use a “fast charger” to provide starting voltage.
Vehicles with the Stop/Start system will be equipped with two batteries. Both the main and the supplemental batteries must be disconnected to completely de-energize the 12 Volt electrical system.
If the negative battery cables are not isolated properly it can cause a potential power spike or surge in the system, resulting in damage to essential electrical components.

Adding Washer Fluid

The fluid reservoir for the windshield washers and the rear window washer (if equipped) is shared. The fluid reservoir is located in the engine compartment...

Cleaning the engine compartment with a high pressure washer is not recommended. CAUTION! Precautions have been taken to safeguard all parts and connections however, the pressures generated by these machines is such that complete protection against water ingress cannot be guaranteed...

Other information:

Jeep Wrangler 2018-2026 Owners Manual: Bulk Fuel Storage — Diesel Fuel

If you store quantities of fuel, good maintenance of the stored fuel is also essential. Fuel contaminated with water will promote the growth of “microbes.” These microbes form “slime” that will clog the fuel filtration system and lines. Drain condensation from the supply tank and change the line filter on a regular basis...

Jeep Wrangler 2018-2026 Owners Manual: FUEL REQUIREMENTS — GASOLINE ENGINE

While operating on gasoline with the required octane number, hearing a light knocking sound from the engine is not a cause for concern. However, if the engine is heard making a heavy knocking sound, see a dealer immediately. Use of gasoline with an octane number lower than recommended octane can cause engine failure and may void the New Vehicle Limited Warranty...

Automatic Headlights — If Equipped, Lights-On Reminder

Automatic Headlights

This system automatically turns the headlights on or off according to ambient light levels. To turn the system on, rotate the headlight switch clockwise to the last detent for automatic headlight operation. When the system is on, the headlight time delay feature is also on. This means the headlights will stay on for up to 90 seconds after you place the ignition into the OFF position. To turn the automatic system off, move the headlight switch out of the AUTO position.