Electric Scooter Troubleshooting Guide > Motor Runs But Not With a Rider On the Vehicle

Motor Runs But Not With a Rider On the Vehicle

Overview

When a motor runs however it does not run when the weight of a rider is on the vehicle that is caused by a battery pack that is dropping power under load and not providing enough power to run the scooter with a rider on it. This is often caused by an old, worn out, or faulty battery pack. However, it can also be caused by a problem with the charging system which is causing the battery pack to not be recharged.

Test The Voltage Of The Battery Pack

(Tool Needed: Multimeter) A multimeter can be used to test the Voltage of the battery or battery pack and determine what its state of charge level is. A good battery or battery pack Voltage will be at or near a 100% state of charge level after it has been recharged. We have a Battery State of Charge Chart to help determine what the battery or battery pack state of charge level is. When a battery or battery pack is below a 0% state of charge then it is over-discharged and it may be damaged and not be able to take a charge. When a battery or battery pack is above a 0% state of charge and has been charged and after charging it the Voltage is significantly below a 100% state of charge that points toward a problem with the charging system. When a battery or battery pack has been charged and it is at or near a 100% state of charge, however the vehicle has little or no power, then presuming that all of the other parts of the scooter are good, then that points toward an old, worn out, or faulty battery or battery pack.

Determine The Battery Pack's History

Determine how long has the battery pack has been left in an uncharged state for. If left uncharged for less than 6 months the battery pack may be able to successfully recharged. However if left uncharged for over 6 months then it may or may not be able to be recharged. If you know that the scooter has been sitting for a long time without being recharged then there is a higher probability that the battery pack has become over-discharged and will no longer accept a charge. The battery or battery pack Voltage can be tested to determine of it is over-discharged. We have a Battery State of Charge Chart to help determine what the battery or battery pack state of charge level is. If the battery or battery pack state of charge level is under 0% then it is over-discharged. When a lead-acid battery or battery pack has been over-discharged then some of its cells may reverse their polarity and if this happens then the battery or battery pack will become faulty and need to be replaced. The most common causes of a battery or battery pack being over-discharged is from accidentally leaving the power switch on for a significant amount of time when the vehicle is not in use, or from not recharging the battery or battery pack frequently enough when the vehicle is not in use. When a vehicle is not being used it should be recharged every 30 days to keep the battery or battery pack maintained at a 100% state of charge.

Try Deep Charging The Battery Pack for 48 to 72 Hours

Sometimes lead-acid battery packs need a deep charge to equalize the cells and help the battery pack regain capacity. Try charging the battery pack for 48 to 72 hours and then see if that helps. It is a good practice to perform a deep charge a couple of times a year or whenever a significant loss of capacity is noticed.

Test The Battery Charger Port

(No Tools Needed) Please note that not all battery chargers have a light that turn green when plugged into the charger port, so this test will only work with battery chargers that do. If the battery charger is plugged into the wall, unplug it. Plug the battery charger into the battery charger port on the scooter and look for an illuminated indicator light on the battery charger. If an indicator light on the battery charger illuminates when the charger is plugged into the scooter then the wiring and wiring connectors going to the charger port are good and the charger port itself is good.

(Tool Needed: Multimeter) If you have a multimeter the battery charger ports Voltage can be tested. The Voltage level present at the charging port should be the same as at the battery pack. If the charger port has male terminals then great care needs to be taken to avoid short circuiting the terminals to each other or to the charger port's housing if it is metal.

Test The Battery Charger

(Tool Needed: Multimeter) After testing the charger port and confirming that it has Voltage then the battery charger can be tested. If the charger port has no Voltage then that issue will need to be fixed before testing the battery charger. To test the battery charger to confirm that it is recharging the battery or battery pack, first test the Voltage of the battery or battery pack to confirm that it is below a 100% state of charge and that it needs to be recharged. We have a Battery State of Charge Chart to help with determining if the battery or battery pack needs to be recharged. Once it has been determined that the battery or battery pack needs to be recharged, plug the battery charger into the vehicle's charger port, and then plug the battery charger into the wall. Next test the Voltage of the battery pack with a digital multimeter to see if its Voltage is slowly climbing. The multimeter should be set to a DC Voltage range that allows reading the tenths or hundreds of a Volt of the battery or battery pack. If the battery or battery pack's Voltage slowly climbs to a higher number then that indicates that the battery charger is recharging the battery or battery pack. Continue to charge the battery or battery pack until the light on the charger indicates that it is fully charged, then test the battery or battery pack Voltage to see if it is at a 100% state of charge as specified in our Battery State of Charge Chart. If the charger is not charging the battery or battery pack up to a 100% state of charge then the charger is faulty.

Test The Battery Pack On A Scooter That Runs

Visit our Battery Pack Load Testing Guide.

Test The Battery Pack On A Scooter That Does Not Run

(Tool Needed: Load Tester) If the scooter is not running, a load test can be performed on its batteries by removing the battery pack from the scooter and taking the individual batteries out. The individual batteries can then be tested with a automotive battery load tester. Most entry level automotive battery load testers place a 100 Amp load on the battery which is too high so an adjustable carbon pile battery load tester is required and should be adjusted to place a 30 Amp load on the batteries.