250A Bluetooth Kill Switch — Control Your Vehicle's Power from Your Phone
Not all battery disconnect switches are the same. The iFJF 250A Bluetooth Kill Switch gives you remote control of your vehicle's electrical system directly from your smartphone — no separate key fob to lose, no manual switch to reach under the hood. Rated for 250A peak / 125A continuous duty, this unit handles the electrical demands of full-size trucks, RVs, and heavy equipment that cheaper 100A switches can't touch.
Most "remote battery disconnects" on the market use basic RF remotes — lose the fob and you're locked out of your own vehicle. The iFJF Bluetooth Kill Switch pairs directly with your phone via a free app (iOS & Android), so your phone is the remote. Bluetooth range reaches up to 30 feet, and the connection is encrypted to prevent unauthorized access.
What Sets This Apart
Bluetooth Control — No Key Fob Needed: Pair with your smartphone (iOS & Android). Your phone is the remote. No batteries to replace in a separate fob, nothing extra to carry
True 250A Peak Rating: Handles the starting current of diesel trucks, RV generators, and heavy-duty winches. Most competitors are 100A max — inadequate for anything beyond a compact car
Weather-Resistant Construction: Sealed enclosure rated for under-hood and exposed installations. Operates reliably in rain, snow, mud, and high-humidity environments
Anti-Theft by Design: Disconnect the battery from your phone — the vehicle is completely dead. Even if a thief has your key, they can't start it
Universal 12V Compatibility: Works with any 12V DC system — cars, trucks, SUVs, RVs, boats, UTVs, ATVs, tractors, and more
Encrypted Connection: Bluetooth pairing uses AES-128 encryption — your neighbor's phone can't randomly connect to your kill switch
Technical Specifications
Rated Voltage
12V DC (not for 24V systems)
Peak Current
250A (cranking / startup surge)
Continuous Current
125A (normal operation)
Control Method
Bluetooth 4.2 (BLE) — iOS 12+ / Android 8+
Bluetooth Range
Up to 30 ft (10 m) open air; ~15 ft through vehicle metal
Connection Security
AES-128 encrypted pairing; one phone at a time
Enclosure Rating
Weather-Resistant (IP65 equivalent — dust-tight, water-jet resistant)
Standby Current Draw
<3mA (negligible — won't drain your battery)
Operating Temperature
-22°F to 185°F (-30°C to 85°C)
App
Free download — "iFJF Connect" on App Store & Google Play
Mounting
Surface mount with included stainless steel hardware
Wiring
4-gauge ring terminals (positive side), 16-gauge control wires
Dimensions
4.7" × 3.1" × 1.8" (120 × 80 × 45 mm)
Certifications
CE / RoHS / FCC
Warranty
1 Year Limited
Compatibility
Designed for any 12V DC system up to 250A peak draw. Confirmed compatible with:
Cars & Trucks: Ford F-150/F-250/F-350, Ram 1500/2500/3500, Chevy Silverado/GMC Sierra, Toyota Tundra/Tacoma, Jeep Wrangler/Gladiator
RVs & Campers: Class A/B/C motorhomes, travel trailers, fifth wheels, camper vans
UTVs & ATVs: Polaris RZR/Ranger, Can-Am Maverick/Defender, Honda Pioneer/Talon, Yamaha YXZ
Marine: Boats, pontoons, jet skis (12V systems only — not for 24V trolling motor circuits)
Other: Tractors, generators, classic cars, project vehicles, fleet trucks
⚠️ NOT for 24V systems. Using on a 24V system will damage the control module. Check your vehicle voltage before ordering.
What's Included
1 × Bluetooth Control Module (sealed enclosure)
1 × 250A Heavy-Duty Relay / Contactor
1 × Wiring Harness (4-gauge power cables + 16-gauge control wires)
1 × Stainless Steel Mounting Hardware Kit
1 × Quick Start Installation Guide
Installation Overview
Disconnect battery negative terminal first, then positive
Mount the relay near the battery using included hardware — keep away from exhaust manifolds
Connect power cables: Battery positive → relay input → relay output → vehicle main positive cable
Connect control module to relay using the 16-gauge control wire harness
Mount control module in a dry, accessible location (under dash, glovebox, or engine bay fender well)
Download the app ("iFJF Connect"), pair via Bluetooth, and test
Reconnect battery and test operation: toggle ON/OFF from your phone
Estimated install time: 45–60 minutes for a DIY mechanic comfortable with basic wiring. Professional installation recommended if you're not familiar with automotive electrical systems.
Real-World Use Cases
🔒 Anti-Theft: Park at a trailhead, airport lot, or street — kill the battery from your phone. Even with your keys, the vehicle won't crank
🏕️ RV Battery Management: Disconnect the house battery when in storage to prevent parasitic drain. No more dead batteries after weeks of sitting
🚜 Fleet / Equipment: Disable vehicles and equipment remotely to prevent unauthorized use on job sites
🏎️ Classic Car Storage: Kill power completely during winter storage to prevent electrical fires from aging wiring
🛻 Off-Road / Overlanding: Quick disconnect if you need to work on electrical accessories or in an emergency
Why Choose iFJF Direct?
Quality Assurance: Every unit is tested before shipping — relay cycle-tested, Bluetooth module paired and verified
USA-Based Inventory: Ships from our US warehouse — no waiting for international freight
Expert Support: Our team knows diesel, automotive, and RV electrical systems. Real answers from real people
Fair Pricing: Premium components without the premium markup — direct value to you
Hassle-Free Returns: 30-day return policy. If it doesn't fit or meet your expectations, we'll make it right
Frequently Asked Questions
Q: What's the difference between this Bluetooth kill switch and the cheap RF remote switches on eBay?A: Three key differences: (1) Control method — this uses your smartphone via Bluetooth, not a separate RF key fob that can be lost, broken, or have its battery die. (2) Current rating — 250A peak / 125A continuous vs. typical 100A on cheap units. If you have a diesel truck with dual batteries or high-compression engine, a 100A switch will weld itself closed under cranking load. (3) Security — AES-128 encrypted pairing means only YOUR phone can control the switch. RF remotes use fixed codes that can be intercepted with a $20 SDR radio.
Q: Can I use this on a 24V system?A: No. This product is designed for 12V DC systems only. Using it on a 24V system (common in heavy trucks, some boats, and military vehicles) will damage the control module electronics. Check your vehicle's battery configuration before ordering.
Q: What happens if my phone dies or I lose Bluetooth connection?A: The relay maintains its last state — if it was ON when you lost connection, it stays ON. If it was OFF, it stays OFF. You can always reconnect when your phone is charged or back in range. For emergency situations, you can manually bypass the relay by disconnecting the control wires and connecting the power cables directly (standard tools required).
Q: Will this drain my battery when the vehicle is off?A: The Bluetooth module draws less than 3mA in standby — roughly the same as your car's clock or alarm system. On a healthy battery, this is negligible for weeks or even months of storage. If you're storing the vehicle for more than 3 months, we recommend a battery maintainer regardless of whether a kill switch is installed.
Q: Is this weatherproof enough for under-hood installation?A: Yes — the control module is sealed to IP65 equivalent (dust-tight and resistant to water jets). It's designed for under-hood use where it may be exposed to rain, road spray, and engine wash-downs. The relay/contactor is also weather-resistant. We do not recommend full submersion (e.g., mounting inside a wheel well that gets submerged during water crossings).
Q: Can multiple phones pair to the same kill switch?A: One active connection at a time. You can pair multiple phones, but only one can control the switch at any given moment. This prevents conflicts — if you and your spouse both have the app, whoever connects first has control until they disconnect.
Q: Does this affect my vehicle's ECU, radio presets, or clock?A: When you disconnect the battery, yes — the ECU will reset (relearns fuel trims after a few drive cycles), radio presets will be lost, and the clock will need resetting. This is normal for any battery disconnect. If preserving settings is important, consider using the kill switch only for anti-theft (OFF when parked) and keeping it ON during daily driving.
Q: Can I install this myself?A: Yes, if you're comfortable with basic automotive wiring (crimping ring terminals, routing wires, mounting brackets). The included quick-start guide walks you through it step by step. If you've ever installed a car stereo or aftermarket lights, you can handle this. Professional installation is always an option if you'd prefer.
Product Overview
250A Bluetooth Kill Switch — 12V Remote Battery Disconnect for Car Truck RV UTV is a premium-quality replacement component engineered for exact fitment and reliable performance. Manufactured to meet or exceed OEM specifications using high-grade materials, this part delivers dependable service life for your equipment.
Key Features
RV-Specific Engineering: Designed specifically for recreational vehicle applications.
Direct OEM Replacement: Matches factory specifications for hassle-free installation.
Weather-Resistant: Built to withstand temperature extremes and outdoor exposure.
Quality Assured: Backed by iFJF warranty and US-based customer support team.
Fast Shipping: Ships from US warehouse — arrives in 3-5 business days.
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