Locating the auxiliary battery in a 2016 Jeep Grand Cherokee is a common maintenance task for owners troubleshooting electrical issues or upgrading components. While the primary battery powers the engine start, the secondary battery supports accessories, infotainment systems, and aftermarket installations. Understanding the specific location helps streamline diagnostics and ensures safe electrical work on the vehicle.
Factory Battery Configuration Overview
The 2016 Jeep Grand Cherokee typically comes equipped with a standard 12-volt lead-acid battery as its primary power source, usually situated in the front engine compartment. Many models, especially higher trims or those with advanced infotainment systems, include an auxiliary battery to balance electrical load and protect sensitive electronics. This setup allows the vehicle to manage power distribution more efficiently, supporting features like premium audio systems, rear-seat entertainment, and dual-zone climate control without draining the starter battery.
Primary Location Under the Hood
For the majority of 2016 Jeep Grand Cherokee models, the auxiliary battery is located in the front engine compartment, secured near the fender well on the passenger side. It is typically housed in a black plastic casing and connected to the vehicle’s electrical system via a dedicated fuse and relay assembly. Owners can identify it by looking for a secondary battery terminal with a red cover, often positioned closer to the center of the engine bay to optimize weight distribution.
Identifying the Auxiliary Battery Terminals
When inspecting the area, look for a smaller battery unit, often rectangular in shape, connected with thick red and black cables. The positive terminal is usually marked with a “+” sign and protected by a colored cap, while the negative terminal connects to the vehicle’s chassis ground. Labeling such as “AUX BAT” may be present on the nearby fuse box cover or wiring harness to assist with identification during maintenance or installation.
Alternative Mounting Locations
In some configurations, particularly in models with enhanced power requirements or specialized packages, the auxiliary battery may be relocated to the rear cargo area. This design helps balance vehicle weight and reduces electrical resistance for critical systems. When situated behind the rear seat, the battery is typically enclosed in a ventilated tray with accessible terminals through a panel in the cargo floor.
Checking the Rear Cargo Compartment
To verify this location, open the rear hatch and inspect the spare tire well or side panels. Look for a sealed battery box with wiring harnesses exiting toward the rear bulkhead. This setup is more common in Limited, Overland, and Summit trims, where additional electronics are factory-installed. Always refer to the vehicle’s wiring diagram in the owner’s manual before attempting any disconnections or replacements.
Safety and Maintenance Tips
Working with the auxiliary battery requires caution due to the risk of short circuits, especially when dealing with metal tools near exposed terminals. Always disconnect the negative terminal first using the appropriate wrench size, and ensure the vehicle is turned off before beginning any procedure. Corrosion buildup around the terminals should be cleaned with a baking soda solution and a wire brush to maintain optimal conductivity and connection integrity.
When to Replace or Upgrade
Signs that the auxiliary battery needs attention include dimmed interior lights, malfunctioning infotainment systems, or failure of rear-seat electronics. A voltage test using a multimeter can confirm whether the battery is holding a proper charge. When replacing, use a battery with the same or higher cold cranking amps (CCA) rating and ensure it is securely mounted to prevent vibration damage in the engine compartment or cargo area.
