Description
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The True® 4th gen 4runner dual battery kit comes with all necessary mounting hardware, allowing for easy secure installation. It works with dry cells, flooded lead-acid batteries, AGMs, and hybrids.
True® 4Runner battery isolator works
1. Separation of Functions: Typically, one battery is used for starting the engine (the starter battery), and the other is used for powering auxiliary devices, such as lights, radios, refrigerators, and other electronic devices when the engine is off. The 4th gen 4runner dual battery kit ensures that the starter battery remains fully charged and unaffected by the drain from auxiliary devices.
2. Simultaneous Charging: When the engine is running, the alternator generates electricity, which the 5th gen 4runner dual battery kit then uses to charge both batteries. However, it prioritizes the starter battery to ensure it is always fully charged and ready to start the engine. Once the starter battery is fully charged, the isolator then directs charge to the service battery.
3. Prevent Battery Drain: Without a True 4runner battery isolator, using auxiliary devices could potentially drain the starter battery, leaving you unable to start the vehicle or boat. The isolator prevents this by ensuring that only the service battery is used for auxiliary power.
4. Optimal Charging: True® dual battery isolator for 3rd, 4th, 5th 4runners are designed to manage different types of batteries that may have different charging needs. They ensure that each battery receives the correct charge required to maintain its health and longevity.
5. Safety and Reliability: By separating the batteries and managing their charge independently, (3rd,4th,5th,SDHQ) 4runner dual battery kit improve the overall safety and reliability of the vehicle’s electrical system. This setup helps in reducing the likelihood of electrical failures and extends the life of the batteries.
“I run a 2021 Chevy Silverado with dual batteries, a winch, and a sound system with a large speaker setup that hits hard. Before installing the True® Large Battery Isolator, I was always second-guessing my setup—especially during long job sites or weekend overlanding trips.
This isolator changed everything. It automatically manages the charge between my starter and auxiliary batteries without me lifting a finger. No switches, no worries. I can run my gear all day and still fire up the truck without hesitation.
Install was clean, and the unit feels built for real-world abuse. If you’ve got a Silverado and serious power needs, this isolator is the upgrade you didn’t know you needed—but won’t want to live without.”
Austine Jones, Arizona
Frequently Asked Questions
1. What is P.E.P.® (Proprietary Efficiency Programming)?
- P.E.P.® is TrueAm’s smart logic that optimizes battery protection and charging efficiency.
- It ensures the isolator only connects when safe and beneficial for both batteries
2. Does it regulate charging amps?
- No, the SBI doesn’t regulate amperage. That’s handled by your alternator and voltage regulator.
- The SBI simply controls when the second battery is connected based on voltage thresholds.
3. Why should I use this kit?
- Prevents your main battery from being drained by accessories.
- Provides dependable power for winches, lights, inverters, and other gear.
- Ensures your truck always has starting power available.
4. Can I manually override or shut it off?
- The male connector underneath can be wired for remote shutoff.
- Inline switches are optional but not required—SBI handles disconnection automatically.
5. How do I monitor battery status?
- Optional Single Meter Dual Display (SMDD) shows real-time voltage for both batteries.
- Saves space and simplifies monitoring
Kenny Storkie –
For my fourth-generation Toyota 4Runner, I purchased these truck battery isolators. The main concern with this product is the voltage-sensitive relay. For my auxiliary battery, I used a stock battery hood-down kit and 1/4″ eye bolts.
I discovered that the relay was not functional during the initial installation.
Change the relay’s battery leads if this occurs to you. The back of mine has a mistaken label. Make sure the ground line is securely fastened to the relay. It operates perfectly, and I’m very happy about that.
Eli Patterson –
Installed easily and comes with simple instructions. Does an excellent job of keeping my backup battery charged. It also features a relay that reverses the flow of electricity to your main battery, which works quite well. It’s nice to know you can jump start yourself.
Aaron Watkins –
I require a lot of power in my Toyota Tundra for business. My main starter battery has dropped too low to start several times. The True Smart Battery Isolator resolves the issue. The only thing I would change is to acquire a package with an additional 6′ of power wire.
Martin Ward –
Great Toyota dual battery system! I placed a second 100 amp Renogy AGM battery with an inverter, cigarette lighter, and USB ports in the back of my Tundra truck roof. Easy to wire, with excellent directions.
Hector Ward –
It’s not too complicated since it accomplishes what it’s supposed to do. I drove 1700 miles in my Tundra with peace of mind considering that I kept my second battery ready in case of a problem.
Marlin Ward –
It works well after a quick installation to my , and the manufactuirer should spend in research and development. My 2018 Toyota 4runner requires somewhat more application than what the instructions specify.
Felandia Green –
I purchased a smart battery isolator for my fourth-generation Toyota 4Runner, making it the centerpiece of my design. To secure the auxiliary battery, I used 1/4-inch eye bolts in conjunction with a factory battery hold-down kit.
During the initial installation, I encountered an issue with the relay—it was not functioning. If you experience a similar problem, check the battery leads on the relay; in my case, they were mislabeled on the reverse side. Additionally, ensure that the ground cable is securely connected to the relay.
Once everything was properly set up, the system operated flawlessly. I couldn’t be more pleased with its performance!