Noco GB40 Boost Plus User Manual product img

Noco GB40 Boost Plus User Manual

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Noco GB40 Boost Plus User Manual

Noco GB40 Boost Plus User Manual product img


Electrical Shock.
The product is an electrical device that can shock and cause serious injury. Do not cut power cords. Do not submerge in water or get wet.

Unmonitored, incompatible, or damaged batteries can explode if used with the product. Do not leave the product unattended while in use. Do not attempt to jump-start a damaged or frozen battery. Use products only with batteries of recommended voltage. Operate products in well-ventilated areas.

The product is an electrical device that emits heat and is capable of causing burns. Do not cover the product. Do not smoke or use any source of electrical spark or fire when operating the product. Keep product away from combustible materials.

Eye Injury.
Wear eye protection when operating the product. Batteries can explode and cause flying debris. Battery acid can cause eye and skin irritation. In the case of contamination of eyes or skin, flush the affected area with running clean water and contact poison control immediately.

Explosive Gases.
Working in the vicinity of lead acid is dangerous. Batteries generate explosive gases during normal battery operation. To reduce the risk of battery explosion, follow all safety information instructions and those published by the battery manufacturer and manufacturer of any equipment intended to be used in the vicinity of the battery. Review cautionary markings on these products and on the engine.

Important Safety Warnings

Proposition 65.
WARNING: This product can expose you to chemicals including lead and exhaust fumes, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to

Personal Precaution.
Only use the product as intended. Someone should be within range of your voice or close enough to come to your aid in case of emergency. Have a supply of clean water and soap nearby in the case of battery acid contamination. Wear complete eye protection and protective clothing while working near a battery. Always wash your hands after handling batteries and related materials. Do not handle or wear any metal objects when working with batteries including; tools, watches, or jewelry. If metal is dropped onto the battery, it may spark or create a short circuit resulting in electrical shock, fire, or explosion which may result in injury, death, or property damage.

Handle product with care. The product can become damaged if impacted. Do not use a damaged product, including, but not limited to, cracks to the casing or damaged cables. Do not use the product with a damaged power cord. Humidity and liquids may damage the product. Do not handle the product or any electrical components near any liquid. Store and operate products in dry locations. Do not operate the product if it becomes wet. If the product is already operating and becomes wet, disconnect it from the battery and discontinue use immediately. Do not disconnect the product by pulling on the cables.


Do not attempt to alter, modify or repair any part of the product. Disassembling a product may cause injury, death or damage to property. If a product becomes damaged, malfunctions, or comes in contact with any liquid, discontinue use, and contact NOCO. Any modifications to the product will void your warranty.

This product is only approved for use with NOCO accessories. NOCO is not responsible for user safety or damage when using accessories not approved by NOCO.

Prevent battery acid from coming in contact with the product. Do not operate the product in a closed-in area or an area with restricted ventilation. Do not set a battery on top of the product. Position cable leads to avoiding accidental damage by moving vehicle parts (including hoods and doors), moving engine parts (including fan blades, belts, and pulleys), or what could become a hazard that may cause injury or death.

The product is only compatible with 12-volt lead-acid batteries only. Do not attempt to use the product with any other type of battery. Jump-starting other battery chemistries may result in injury, death, or property damage. Do not jump-start a battery if you are unsure of the battery’s specific chemistry or voltage.

The Battery.

The built-in lithium-ion battery in the product should be replaced only by NOCO and must be recycled or disposed of separately from household waste. Do not attempt to replace the battery yourself and do not handle a damaged or leaking lithium-ion battery. Never dispose of batteries in household trash. Disposal of batteries in household trash is unlawful under state and federal environmental laws and regulations. Always take used batteries to your local battery recycling center. If the product battery is excessively hot, emitting an odor, deformed, cut, or is experiencing or demonstrating an abnormal occurrence, immediately stop all use and contact NOCO.

Battery Charging.

Charge the product with the included USB charge cable and a NOCO 10W 12V power adapter. A third-party USB cable and 5W or 10W power adapter that are compatible with USB 2.0 or power adapters compliant with one or more of the following standards EN 301489-34, IEC 62684, YD/T 1591-2009, CNS 15285, ITUL.2000. Be cautious of using low-quality power adaptors, as they may present a serious electrical risk that can result in injury to person, Device, and property.

If using a third-party USB power adapter, contact the manufacturer(s) to find out if your power adapter complies with the above standards. Using damaged cables or chargers, or charging when moisture is present, can result in electric shock. Using a generic or third-party power adapter may shorten the life of your product and cause the product to malfunction. NOCO is not responsible for the user’s safety when using accessories or supplies that are not approved by NOCO. When using a USB Power Adapter to charge the product, make sure that the AC plug is fully inserted into the adapter before you plug it into a power outlet.

Power adapters may become warm during normal use, and prolonged skin contact may cause bodily Important Safety Warnings EN injury. Always allow adequate ventilation around power adapters when using them. To ensure maximum battery life, avoid charging your product for more than a week at a time, as overcharging may shorten battery life. Over time, an unused product will discharge and must be recharged before use. Disconnect the product from power sources when not in use. Use the product only for their intended purposes.

How To Use

Charge the GB40.
The GB40 comes partially charged out of the box and needs to be fully charged prior to use. Connect the GB40 using the included USB Charge Cable to the USB IN port and the USB car charger. It can also be recharged from any USB-powered port, like an AC adapter, car charger, laptop, and more. The USB IN port is rated at 2.1 Amps to ensure safe and efficient charging of the internal lithium battery. Due to FCC regulations, we recommend not to charge and discharge the unit at the same time. The time to recharge a GB40 will differ based on the discharge level and the power source used. Actual results may vary due to battery conditions.

Noco GB40 Boost Plus User Manual fig 1

When recharging, the charge level of the internal battery is indicated by the Charge LEDs. The LEDs will slowly pulse ‘On’ and ‘Off’ and become solid until all four Charge LEDs are on. When the battery is fully charged, the Green 100% LED will be solid, and the 25%, 50%, and 75% Charge LEDs will turn “Off”. From time to time, the Green 100% LED will pulse indicating maintenance charging is occurring.

Connect to the Battery.

Carefully read and understand the vehicle owner’s manual on specific precautions and recommended methods for jump-starting the vehicle. Make sure to determine the voltage and chemistry of the battery by referring to your battery owner’s manual prior to using this product. The GB40 is for jump-starting 12-volt lead-acid batteries only. Before connecting to the battery, verify that you have a 12-volt lead-acid battery. The GB40 is not suitable for any other type of battery.

Identify the correct polarity of the battery terminals on the battery. The positive battery terminal is typically marked by these letters or symbols (POS, P,+). The negative battery terminal is typically marked by these letters or symbols (NEG, N,-). Do not make any connections to the carburetor, fuel lines, or thin, sheet metal parts. The below instructions are for a negative ground system (most common). If your vehicle is a positive ground system (very uncommon), follow the below instructions in reverse order.

  1. Connect the battery clamps to the GB40 by connecting to the 12V OUT port.
  2.  Connect the positive (red) HD battery clamp to the positive (POS, P,+) battery terminal.
  3. Connect the negative (black) HD battery clamp to the negative (NEG, N,-) battery terminal or vehicle chassis.
    When disconnecting, disconnect in the reverse sequence, removing the negative first (or positive first for positive ground systems).

Jump Starting.

  1. Make sure all of the vehicle’s power loads (headlights, radio, air conditioning, etc.) are turned off before attempting to jump-start the vehicle.
  2. Press the Power Button to begin jump-starting. All LEDs will flash, indicating that all LEDs are properly functioning. If you are properly connected to the battery, the White Boost LED will illuminate. If the battery clamps are connected in reverse, the Red Error LED will illuminate. Reverse the connections to clear this error and then the White Boost LED will illuminate. The White Boost LED is illuminated when the GB40 is ready to jump-start your vehicle.
  3. Try starting the vehicle. Most vehicles will immediately start. Some vehicles may require the GB40 to be connected for up to 30 seconds before starting. If the vehicle does not start right away, wait 20-30 seconds and try again. Do not attempt more than five (5) consecutive jump starts within a fifteen (15) minute period. Allow the GB40 to rest for fifteen (15) minutes before attempting to jump-start the vehicle again.
  4. Once you have started your vehicle, disconnect the battery clamps, and remove the GB40.

Low Voltage Batteries & Manual Override
. The GB40 is designed to jump-start 12-volt lead-acid batteries down to 2 volts. If your battery is below 2 volts, the Boost LED will be “Off”. This is an indication that the GB40 can not detect a battery. If you need to jump-start a battery below 2 volts there is a Manual Override feature, which allows you to force “On” the jump-start function.


Noco GB40 Boost Plus User Manual fig 2

  1. Internal Battery Level Indicates the charge level of the internal battery.
  2. Error LED Illuminates Red if reverse polarity is detected, or blinks “On” and “Off” when the internal battery temperature is too high.
  3. Power Button Push to turn unit “On” & “Off”.
  4. Power LED Illuminates White when the unit is “On”.
  5. Boost LED Illuminates White when Boost is active. If the unit is connected properly to a battery, the GB40 will automatically detect a battery and go into Boost mode (LED flashes White when the Manual Override feature is active).
  6. Manual Override Button To enable, push, and hold for three (3) seconds. WARNING: Disables safety protection and manually forces Boost “On”. Only for use when a battery is too low to be detected.
  7. Light Mode Button Toggles the ultra-bright LED light through 7 light modes: 100% > 50% > 10% > SOS > Blink > Strobe > Of


Error LED: Solid Red
Reverse polarity/Reverse the battery connections

Error LED: Blinking Red w/Cables Connected Proper
The internal battery is too hot/ Allow the unit to cool. Bring the unit into a cooler environment.

Boost Light Does Not Come On w/Cables Connected Properly
The connected battery is below 2 volts/ Remove all loads, and try again, or use Manual Override Mode.

Technical Specifications

  • Internal Battery: Lithium Ion
  • Peak Current Rating: 1000A
  • Operating Temperature: -20°C to +50°C
  • Charging Temperature: 0ºC to +40ºC
  • Storage Temperature: -20ºC to +50ºC (Avg Temp.)
  • Micro USB (Input): 5V, 2.1A
  • USB (Output): 5V, 2.1A
  • Housing Protection: IP65 (w/Ports Closed)
  • Cooling: Natural Convection
  • Dimensions (L x W x H): 6.7 x 3.2 x 1.7 Inches
  • Weight: 2.4 Pounds


NOCO warrants that this product (the “Product”) will be free from defects in material and workmanship for a period of one (1) year from the date of purchase (the “Warranty Period”). For defects reported during the Warranty Period, NOCO will, at its discretion, and subject to NOCO’s technical support analysis, either repair or replace defective Products. Replacement parts and products will be new or serviceably used, comparable in function and performance to the original part, and warranted for the remainder of the original Warranty Period.

This Limited Warranty is made solely for the benefit of the original purchaser of the Product from NOCO or from a NOCO-approved reseller or distributor and is not assignable or transferable. To assert a warranty claim, the purchaser must: (1) request and obtain a return merchandise authorization (“RMA”) number and return location information (the “Return Location”) from NOCO Support by emailing or by calling 1.800.456.6626; and (2) send the Product, including RMA number, receipt or a warranty fee (fee required only if not providing receipt) of 45% of MSRP of the defective Product (the “Warranty Fee”) [RMA will include applicable Warranty Fee amount] to the Return Location.

NOCO One (1) Year Limited Warranty.

DO NOT SEND IN THE PRODUCT WITHOUT FIRST OBTAINING AN RMA FROM NOCO SUPPORT. THE ORIGINAL PURCHASER IS RESPONSIBLE (AND MUST PREPAY) FOR ALL PACKAGING AND TRANSPORTATION COSTS TO SHIP PRODUCTS FOR WARRANTY SERVICE. NOTWITHSTANDING THE ABOVE, THIS LIMITED WARRANTY IS VOID AND DOES NOT APPLY TO PRODUCTS THAT: (a) are misused, mishandled, subjected to abuse or careless handling, accident, improperly stored, or operated under conditions of extreme voltage, temperature, shock, or vibration beyond NOCO’s recommendations for safe and effective use; (b) improperly installed, operated or maintained;

(c) are/were modified without the express written consent of NOCO; (d) has been disassembled, altered or repaired by anyone other than NOCO; (e) the defects of which were reported after the Warranty Period. THIS LIMITED WARRANTY DOES NOT COVER: (1) normal wear and tear; (2) cosmetic damage that does not affect functionality; or (3) Products where the NOCO serial number is missing, altered, or defaced. You may register your NOCO product online at: no. co/register. If you have any questions regarding your warranty or product, contact NOCO Support (email and phone number above) or write to: The NOCO Company, at 30339 Diamond Parkway, #102, Glenwillow, OH 44139 USA.


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