Frequently Asked Questions

Frequently Asked Questions

NOCO GeniusPRO Professional Battery Chargers.

GENIUSPRO25 User Guide
GENIUSPRO50 User Guide

The warranty is 3 years from the proof of purchase or manufacture date (based on serial number).

NOCO GeniusPRO chargers are equipped with LED indicators to indicate standby, charging modes, charge levels and for advanced diagnostics.

GENIUSPRO25 Understanding the Interface.
GENIUSPRO50 Understanding the Interface.

GENIUSPRO25 2.7 lbs (1.22kg)
GENIUSPRO50 5 lbs (2.27kg)

GENIUSPRO25 25A (6V, 12V), 12.5A (24V) DC
GENIUSPRO50 50A (6V, 12V), 25A (24V) DC

GENIUSPRO25 375 Watts (Max)
GENIUSPRO50 750 Watts (Max)

Selecting the appropriate charger for your battery will depend on its Amp-Hour (Ah) capacity size. This is usually listed on the battery label at the 20-hour rate, example: “100 AH @ 20HR”. Check your battery for its rated Amp-hour capacity.

GENIUSPRO25 (6V and 12V) Up to 1000Ah, (24V) Up To 500Ah
GENIUSPRO50 (6V and 12V) Up to 2000Ah, (24V) Up To 1000Ah

Check out the next question What are the charging times for GeniusPro? to learn more.

These are proximate charging times for a battery at 50% depth of discharge.


GENIUSPRO25

GENIUSPRO50
50 Amp Hour 1.5 hours 0.8 hours
100 Amp Hour 3 hours 1.5 hours
200 Amp Hour 6 hours 3 hours
500 Amp Hour 15 hours 7.5 hours
1000 Amp Hour 30 hours 15 hours

NOCO GeniusPro chargers are compatible with 6V, 12V & 24V batteries, including all types of 12V lead-acid, AGM and lithium-ion batteries.


GENIUSPRO25 IP20
GENIUSPRO50 IP20

GENIUSPRO25 30 AMP ANL Fuse
GENIUSPRO50 60 AMP ANL Fuse

When plugged into AC power for the first time NOCO GeniusPro will start out in Standby Mode. Press the Mode Button to switch between modes. To access 6V or 24V charging modes press and hold the Mode Button for 3 seconds then toggle the Mode Button to the desired battery type.

How to Change Modes on GeniusPRO Chargers


Repair is an advanced battery recovery mode for repairing and storing, old, idle, damaged, stratified or sulfated batteries. Not all batteries can be recovered. Batteries tend to become damaged if kept at a low charge and/or never given the opportunity to receive a full charge. The most common battery problems are battery sulfation and stratification. Both battery sulfation and stratification will artificially raise the open circuit voltage of the battery, causing the battery to appear fully charged, while providing low capacity. Use Repair in attempt to reverse these problems. For optimal results, take the battery through a full charge cycle, bringing the battery to full charge, before using this mode. Repair Mode can take up to four (4) hours to complete the recovery process and will return to Standby when completed. Repeated repair cycles may be needed depending on size and condition of the battery, however battery temperature must be closely monitored.

CAUTION: USE THIS MODE WITH CARE. THIS MODE IS FOR 6-VOLT, 12-VOLT AND 24-VOLT LEAD-ACID BATTERIES ONLY. THIS MODE USES A HIGH CHARGING VOLTAGE AND MAY CAUSE SOME WATER LOSS IN WET (FLOODED) CELL BATTERIES. BE ADVISED, SOME BATTERIES AND ELECTRONICS MAY BE SENSITIVE TO HIGH CHARGING VOLTAGES. TO MINIMIZE RISKS TO ELECTRONICS, DISCONNECT THE BATTERY BEFORE USING THIS MODE.

Using Repair Modes on GeniusPRO


Supply Mode converts the charger to a constant voltage DC power supply. It can be used to power 12VDC and devices, tire inflators, seat heaters and more. As a power supply, it can also be used to retain a vehicle’s on-board computer settings during battery repair or replacement.

13.6V Supply (12V Supply) provides 13.6-volts up to 25A. Charger output voltage will drop if output load exceeds the 25A current limit.

27.2V Supply (24V Supply) provides 27.2-volts up to 12.5A. Charger output voltage will drop if output load exceeds the 12.5A current limit.

CAUTION: USE THIS MODE WITH EXTREME CARE. SUPPLY MODE DISABLES SAFETY FEATURES AND LIVE POWER IS PRESENT AT THE CONNECTORS. DO NOT TOUCH CONNECTIONS TOGETHER. RISK OF SPARKS, FIRE, EXPLOSION, PROPERTY DAMAGE, INJURY, AND DEATH.

Using Supply Modes on GeniusPRO


NOCO GeniusPRO is able to detect and charge dead batteries as low as 1-volt. For extremely dead batteries lower than 1-volt, manually turn on Force Mode to detect and charge batteries all the way down to zero volts. Follow the link below to learn how to use Force Mode on GeniusPRO.

How to use Force Mode on GeniusPRO


NOCO GeniusPRO are able to detect and charge dead batteries as low as 1-volt. For extremely dead batteries lower than 1-volt, manually turn on Force Mode to detect and charge batteries all the way down to zero volts.

How to use Force Mode on GeniusPRO


If a charge LED and Standby mode are flashing this means Genius is in Force Mode. After 5 minutes, the charger will return to the normal charge mode operating and low voltage detection will be reactivated.

When in Force Mode all safety features will be disabled.

How to use Force Mode on GeniusPRO


If the Standby LED is illuminated it means that GeniusPRO is in Standby Mode and it is not recognizing that it is connected to a battery. This can happen when there is no battery connected to the charger, if the voltage on the battery is lower than the recognition threshold (1V), if the connection to the battery is faulty, or if the inline fuse is faulty or loose in the fuse housing.

How to use Force Mode on GeniusPRO


Pressing the 5A Mode button activates Reduced Charge Current mode, which will allow the unit to operate at a charge current of 5A. This mode is available at any time and can be used with the following modes only: 12V AGM, 12V LITHIUM, 6V, 6V AGM, 6V LITHIUM, 24V, 24V AGM, 24V LITHIUM and Force mode.


Pressing the 10A Mode button activates Reduced Charge Current mode, which will allow the unit to operate at a charge current of 10A. This mode is available at any time and can be used with the following modes only: 12V AGM, 12V LITHIUM, 6V, 6V AGM, 6V LITHIUM, 24V, 24V AGM, 24V LITHIUM and Force mode.


When GeniusPRO has a slowly pulsating green LED it means the charger is in Maintenance Mode. After the battery is fully charged, the charger will continue to provide ongoing maintenance and optimization until disconnected.

Click here to learn more about the Charge LEDs on GeniusPRO.


If the Overvoltage LED is illuminated, this means the battery's voltage is too high for the charge mode that is selected. For example, if you have a 12V battery and have selected a 6V charging mode selected.


If the Bad Battery Error LED is illuminated, this means that the battery is not holding a charge, or there may be a short in the battery. We recommend taking the battery into a local battery shop for a thorough evaluation of its health and status.


If the Overvoltage, Bad Battery, and Standby LEDs are flashing together, either the charger's internal temperature is too hot, or the ambient temperature is too cold for operation. If the charger's internal temperature is too hot, the charger will stop displaying the error and resume function after the charger cools down. If the ambient temperature is too cold, the charger will resume function when the ambient temperature rises.


Yes. All GeniusPRO units come packaged with a carrying case for that unit. At this time we do not sell replacement carrying case.


All NOCO GeniusPRO Chargers are marked with a unique serial identification number, usually found stamped on the side or edge of the unit. Click the link below to find the serial number location on each model.

Locating the Serial Number on GeniusPRO


Yes, you can find 10 foot extension cables on our online store.

HD 10' Extension Cable For GENIUSPRO25

PRO 10' Extension Cable For GENIUSPRO50


Yes, you can find replacement clamps with eyelets for GeniusPRO on our online store.

HD Battery Clamps With Eyelets For GENIUSPRO25

PRO Battery Clamps With Eyelets For GENIUSPRO50










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It's OK to respond via email for a faster response.

Click for emergency contact information.

Emergency Contact Information

1.800.456.6626 8AM-5PM (MST)
Monday-Friday
For non-urgent support, please Request A Callback
For Fastest Response, Use 'Chat' or 'Send a Message' Above