No announcement yet.

Sur-Ron Light-Bee electrical troubleshooting

This topic is closed.
This is a sticky topic.
  • Filter
  • Time
  • Show
Clear All
new posts

    I can't charge my battery:

    Battery appears to be dead and you cannot charge it?

    Awaking the Battery after Auto-Sleep mode:
    1. Plug the charger into a power bar with a switch (or an outlet with the switch next to it, it's way easier than unplugging/plugging back) . Do not turn on the power bar yet, insert the charger plug into the battery charge port.
    2. Turn on the main power, the moment, the red and green indicators of the charger will alternately blink, turn off the charger and then on again.
    3. The red indicator of the charger will blink fast (0.5 second per time). The blink time will last to 20 seconds.
    4. After the 20 second blink, the red indicator will be a constant light for 10 seconds. During this 10 seconds, turn off at the power point and then on for one time.
    5. After Step 4, the “Forced Charging” function of the charger will be turned on. Then, the charger will work normally
    6. You may need to do this procedure up to 20-30times.

    This video shows you exactly how to do it:

    1. In Step 3, during the red indicator’s 20 seconds fast blink, please do not turn off the charger. Otherwise, you need to start the procedure again from step 1.
    2. In Step 4, the action to turn off and then turn on the charger needs to be finished during the 10 seconds, when the red indicator is constant light. Otherwise, you need to start the procedure again from Step 1.

    If you still can't charge after 30 attempts, skip to the next section below and try step #4 and #6
    Last edited by Sebz; 5 days ago.


      I turn the ignition ON and nothing happens, no lights, horn or dashboard.

      Trouble turning on:

      1.Make sure you turn the key and that it is charged. There is a breaker in front of the battery, breaker needs turned on before operating.

      Click image for larger version  Name:	breaker.png Views:	2 Size:	363.2 KB ID:	90006
      Make sure to also check if the screw terminals are tight, if it's loose the power wire could not be making contact!

      Click image for larger version

Name:	IMG_3040.JPG
Views:	5132
Size:	673.1 KB
ID:	114951

      2. There is a fuse in a small white box, check that the fuse is intact. If not swap it out. There is an extra fuse in the box. Its a 5amp 250 watt fast acting glass fuse (6mmx30mm) if you need another. Without that fuse the controller is not turned ON and the lights and dashboard are not getting any power.

      Click image for larger version  Name:	fuse holder.png Views:	2 Size:	927.9 KB ID:	90007

      Click image for larger version  Name:	fuse.png Views:	2 Size:	300.6 KB ID:	90008

      3. Ignition

      The ignition contacts could be corroded it's pretty common if water got in.

      Remove the 2 bolts holding the USB/ignition assembly and pull from the top, you should have a simple connector with 2 wires, unplug it and measure the continuity between the 2 pins when the switch it ON, if you don't hear a beep them it's possible the switch is finished. You can bypass the switch with a piece of wire to see if the bike will power up.

      Click image for larger version  Name:	IMG_2447.JPG Views:	0 Size:	559.9 KB ID:	104176Click image for larger version  Name:	IMG_2458.JPG Views:	0 Size:	1.24 MB ID:	104177
      Click image for larger version  Name:	IMG_2459.JPG Views:	0 Size:	787.2 KB ID:	104178

      4. Measure the voltage of the battery. T

      Measure the voltage with a multimeter: flip the ignition OFF ,then the breaker OFF, unplug the battery fully, wait 30sec, and measure from the charge port, you should be reading anything between 45V up to 67.2V depending on the state of charge.

      Click image for larger version  Name:	image_17666.jpg Views:	0 Size:	577.8 KB ID:	114360Click image for larger version  Name:	image_21264.jpg Views:	0 Size:	62.8 KB ID:	114361

      Next would be to plug the battery back, measure the voltage from the charge port (see attached) and while measuring flip the breaker ON (note the voltage) then turn the ignition "ON" and measure the voltage again. As you can see in my case the voltage went up a little .. that is because the BMS was sleeping and we just woke him up (really). If you turn off the breaker and wait 30 sec or so the voltage should go back down a little (in this case it dropped 0.4V)

      Click image for larger version  Name:	image_17665.jpg Views:	0 Size:	569.9 KB ID:	114362

      5. IF you had a weird battery reading, like voltage dropping under 45V when you switched the ignition, Unplug both front and rear lights, if one of them is shorted out the main display and the motor wont run. You can access the headlight connector under the ignition and access the rear light connectors from the back of the rear light.

      6.. Battery load testing:

      Best is to use a 120VAC incandescent bulb or a halogen bulb as they work great with any voltage, at 60VDC they will be roughly 30-40% of the regular brightness. If you have a large resistors be aware that you will need to apply a small load like a light bulb before apply a large load of the BMs will trip instantly.

      Unplug the battery from the bike, let it rest for at least 30 secs, measure the voltage from the battery pack. Then connect the light bulb to the discharge port (there is no polarity on a incandescent light bulb). If you see the voltage drop (like these 2 pictures below) then it's likely the battery BMS that has an issue. In this situation please contact

      If not please continue testing

      Click image for larger version  Name:	IMG_1448.JPG Views:	1260 Size:	2.62 MB ID:	91141Click image for larger version  Name:	IMG_1447.JPG Views:	1248 Size:	2.10 MB ID:	91142

      click here to be redirected to the next phase of tests (you can skip step #1 and go to step #2 as you just done it)
      Last edited by Sebz; 09-30-2020, 11:14 AM.


        My Sur-Ron not working or cutting out while riding but the lights and dashboard remains ON

        If the lights/display/horn works and they do not turn off or flicker then continue reading this section

        Can be either:
        1) Brake cutout sensors
        2) Kick stand sensor
        3) Throttle stuck
        4) A connector is not fully "clicked in"

        5) Tilt sensor (crash sensor)
        6) A problematic light

        1) Check the ebrakes. The brake levers are designed to cut power if pulled. In some circumstances such as a crash this connector could come unplugged and the connector may cause intermittent cutout until plugged back into the lever. If you see a cutout, check the ebrake connector! If it is loose of comes out if you pull on it, add a couple drops of superglue to hold it in place.

        Click image for larger version  Name:	brake sensor.png Views:	2 Size:	623.1 KB ID:	90012
        Disabling ebrakes for full throttle during braking

        The goal of ebrakes is to cut power from the motor as a safety measure, however there are instances where this may want to be disabled such as during an actual race, track use, burnouts, or any situation where you need to already be hitting the throttle before you let go of the brake and require extreme agility. Please see the post below for in-depth instructions on how to service the ebrake connection

        2) Kick stand sensor, make sure that the kickstand is up and that the wire is not ripped out of the kickstand (near the pivot). In case of a doubt you can unplug the sensor but you will have to remove the bash guard and access the triangular 3 pin connector and unplug it.

        Click image for larger version  Name:	Screen Shot 2019-07-20 at 1.15.40 PM.png Views:	1 Size:	987.7 KB ID:	90013

        3A) Throttle stuck (only for pre-2020 bikes using the mechanical throttle.)

        Maybe the cable it too tight and the throttle is not returning to 0, you can adjust the throttle cable on the hand throttle adjuster, just slide the rubber boot, loosen the lock ring and turn the adjustment screw in.

        Video explaining how the throttle works. Note: you dont have to remove the Bach guard you can just take a look through the holes in the bash guard to make sure that the cable sheath is in the bracket.

        3B) Electronic throttle wires ripped out of the throttle

        see this section below

        4) A connector is not fully "clicked in"

        There are many connectors on that bike and some are critical, if a wire is pulled out a little or a connector is not fully pressed in then the motor can cut out while riding.

        Now you will have to remove the bash guard to access these connector. Make sure that you do not pull on any connectors or wires!

        Please take a look at this video

        5) Tilt sensor (crash sensor)

        The crash sensor is located under the top part of the controller, if you have disabled the brake & kickstand sensors, adjusted the throttle and checked the connector and you still get cutouts (without ever loosing power to the dashboard and lights) then best would be to unplug this sensor and test the bike. So far we havent replaced a single crash sensor so it's very unlikely that it goes bad. If you take a huge jump and land hard, you can trip that sensor (happened to me) so keep that in mind that this sensor is not for extreme jumps!

        To access this sensor you will have to pull the controller out, it's a little black box between the battery and then top part of the controller.

        Please watch this video on how to change the controller, at the 3:00 min mark Matt is pointing at the crash sensor:

        6) Rear or front light is pulling the brake cut-out signal.

        Disconnect both wires off the rear light and disconnect the front head light (front head light connector is located under the ignition housing). Make sure the 2 rear light wires are not touching anything.
        Last edited by Sebz; 11-02-2020, 12:10 PM.


          My Sur-Ron is slow (speed limited under 30mph)

          Sur-Ron Street legal mode is likely engaged

          Please click this link to see the video on how to change from full power to street legal and vice-versa.

          On the Light-Bee this is a (very) low power mode (like 8-10mph) on the Light-Bee X (LBX) it's a street legal mode (if that applies to your state/country) and it's locked to 25-30mph.

          Now here is the trick, If your bikes was bought before May 2019 then:

          Cutting this wire will limit both power AND speed depending on the model you have . In theory you could put a switch here when you go offroad but the idea is you simply cut the looped green/black wire.

          If your Bike came with the factory street/slow mode, just look for the green/black wire under the black sheath and crimp or solder both ends together (or twist them together if you can't wait!)

          If your bike was bought after May 2019 then: It's the opposite, cutting the green/black wire will make you bike fast again!

          Click image for larger version  Name:	green wire uncut.png Views:	1 Size:	366.9 KB ID:	90015
          Last edited by Sebz; 1 week ago.


            Display and lights works but the motor does not move (Intermittent or not)

            Before continuing with this section make sure you check all the sensors and connections covered here: CLICK ME

            If you have this cable (see below) then open the battery cover, turn the breaker OFF and unplug the battery connecter and connect this harness to the bike and then connect the other end to the battery. The LED will flash is there is a trouble code stored, wire down the code and check the following error code chart

            Click image for larger version  Name:	Sur-Ron cable adapter.jpg Views:	2847 Size:	1.79 MB ID:	90026

            First test should be the wheel spin test, see if the rear wheel spins without much effort. If you can't rotate it with a finger or 2 then it's possible that the controller is shorted out

            Take a look at this video:

            f you havent inspected the connection yet then it's time to do it, dont pull on the wires, just press them in firmly, check if there aren't any wires pulled out of a connector.

            Please watch this video:

            If the motor/rear wheel spins fine and all the sensors are unplugged and you checked every connection then it can still be the controller or a bad connection in the harness. Best would be to take a video of the issue and email
            Last edited by Sebz; 09-08-2020, 08:05 AM.


              Motor works (might be slow too) but the lights/horn/display wont work

              This failure state is uncommon but is something you could look for if having problems.
              The red and black power wires going to the controller has a small red wire soldered to the ring terminal as seen below (The black has the same little wire so check the black too). This goes to the 12VDC voltage converter. If this becomes desoldered or breaks off it will prevent the lights, US, horn and dashboard light up but also could make the motor run slow,

              You will need to pull out the controller you can use this video to help you out removing the controller. Just make sure you removed the battery before proceeding with this

              Once you have the controller pulled out this is what you need to look for:

              Click image for larger version  Name:	little red wire for the DC converter.jpg Views:	1 Size:	674.8 KB ID:	90028


                My Sur-Ron dies completely and/or the lights/dash flash

                Before continuing with this section make sure you check all the sensors and connections covered here: CLICK ME

                Unplug the lights. Both rear lights and any aftermarket modded lights (fisher light headlight etc) . Under a very few limited circumstances we have seen this cause the bike to show as dead.

                If your Sur-Ron display/lights flash 1-6 times and shuts down and 30 sec later it starts to flash again in a loop then it's possibly the battery BMS that is acting up. Best thing you can do is to leave the ignition and breaker ON and then connect the charger to the battery, if the charger is charging you can use the current flowing into the cells to actually power the light and dashboard (and enough to make the wheel spin slowly unloaded) So while charging if the lights stays ON then it's very likely that BMS is acting up. So go down this post to step #4 and do the controller bypass. If the lights and display works then email Luna Cycle at (best would be to make a video of the issue as the support agents will ask for it)

                If you Sur-Ron does not do the 5 flash thing then please continue with the troubleshoot:

                First question, do you have the testing cable (click this link) if yes please turn off the breaker and install it between the bike and battery, flip the breaker and tell me how many times the red LED blinks. IF you dont then please continue. If you do have it and does not blink then please continue.

                The first step would be isolate the issue.. it can be the battery or the controller or just a loose connection.

                1) measure the voltage with a multimeter: flip the ignition OFF ,then the breaker OFF, unplug the battery fully, wait 30sec, and measure from the charge port, you should be reading anything between 45V up to 67.2V depending on the state of charge.

                Click image for larger version  Name:	IMG_1260.JPG Views:	12 Size:	2.32 MB ID:	100594Click image for larger version  Name:	Sur-Ron voltage2.jpg Views:	3218 Size:	227.2 KB ID:	108802

                Next would be to plug the battery back, measure the voltage from the charge port (see attached) and while measuring flip the breaker ON (note the voltage) then turn the ignition "ON" and measure the voltage again. As you can see in my case the voltage went up a little .. that is because the BMS was sleeping and we just woke him up (really). If you turn off the breaker and wait 30 sec or so the voltage should go back down a little.

                Click image for larger version  Name:	IMG_1259.JPG Views:	12 Size:	2.11 MB ID:	100595

                While you are at it inspect the breaker screw-on terminal, if they are loose the wire is maybe not making good contact.

                Click image for larger version

Name:	fetch?id=114951&d=1601493265.jpg
Views:	4953
Size:	673.2 KB
ID:	114952

                2) Next step would be to pull the controller out a little and inspect the the little wires soldered to the main power lug on the controller.

                Just click here to know how to do it and what to look for

                If one is not soldered properly then you will need to solder it back!

                Dont reassemble the bike yet until you test the bike! The next few steps will require you to have the bash guard and controller out.

                3) If you havent inspected the connection yet then it's time to do it, dont pull on the wires, just press them in firmly, check if there aren't any wires pulled out of a connector.

                Please watch this video:

                4) Unplug the DC-DC buck converter from the system and try the bike, you wont get any accessories working but it can help to see if there was an sensor pulling a voltage down, see previous at the 30sec mark to know what to unplug.

                5) ONLY DO THIS STEP IF YOU LIGHTS WERE FLASHING AND DIYING : Now it's time to disconnect the controller power from the battery, so make sure the battery is fully unplugged (very important). Then using an Allen wrench remove the bolts securing the red power terminal, once it's off the controller take some electrical tape and wrap the copper lug so it can't short out on the frame or the negative post. Put the battery back in and flip the breaker ON and the ignition, does the lights and dashboard flicker now or are they staying on? IF they are ON that means the controller is likely damaged and needs to be replaced. If lights are still flickering then it's in the harness or in the battery.

                Just make sure that you tighten the main power lugs back properly, you can use a drop of blue locktite on the thread so it wont loosen up overtime. And while your at it , use dielectric grease over the lugs to prevent oxidation/corrosion! On your next big maintenance inspect your connection again.

                6) If not then chances are that the issue lies in the battery BMS or the wiring harness in the battery. Dont loose hope yet there is a known fix that you will likelly be able to perform and will be a permanent fix! So far 9/10 times it's this little wire!:

                The procedure is on a PDF that you can download here, if you have any questions or unsure about your results please email LunaCycle at , ask for Seb and make sure to write down what tests you did, your measurement and attach photos and videos!
                Attached Files
                Last edited by Sebz; 09-30-2020, 11:16 AM.


                  Error 6

                  As the the error code guide this is a "motor Hoare coil malfunction" We can only suppose that this means "Motor hall sensor malfunction".

                  Now hall sensors are 3 tiny "Hall effect" sensors positioned in the motor and basically their purpose is to tell the controller were the rotor (rotor magnetic fields changes the status of these sensor).

                  So you have 3 phases and each has their hall sensors, Each sensor has 3 pins, one 4.5V supply, one ground (black wire) and the output signal (green yellow and blue). The red and black are common to all 3 sensors. So if you measure the voltage between the black and red (6 pin connector from the motor) you should be getting around 4.3-4.5Vdc. Now to be able to measure the signal of each you will have to be able to rotate the motor very slowly as you will want to see the signal going from 0V to 4.3V each time the magnet crosses each hall sensor.

                  Best way to do this is to remove the plastic cover of the main output shaft of the motor and put a 17mm socket wrench in it, so that way you will be able to turn the motor one notch at a time. But before you test anything make sure that the connector is good and that all the pins are making contact and no wire is pulled out.

                  You also need to unplug every sensor before your start this test, it's possible that a bad sensor could be influencing the hall sensor signal, so please make sure all your sensors are unplugged before testing (crash sensor, kickstand, brakes)

                  Click image for larger version  Name:	IMG_2433.JPG Views:	0 Size:	1.26 MB ID:	104180

                  Now the next step will require you to flip the bike over and remove the bash guard to access the hall sensor connector. Make sure to turn the ignition OFF and leave the battery in. You don't need to remove the controller and motor like I did on the video... the motor was already out so I left it there so it would be easier to show you.

                  You will need a multimeter with good "pointy" tip and likely a second set of hands to turn the motor while you probe the voltage.

                  Now start by turning the ignition to ON and then measure the voltage from the RED and BLACK core, you can poke through the wire insulation if your meter tips are too fat to fit the back of the connector. Just make to to wrap them in electrical tape after. You should measure a constant 4.3-4.5Vdc, I will use 4.5V as a reference.

                  Next move your red probe to any of the 3 hall sensor signal wire (Bleu, yellow or green), you will either measure a 0V (or very low voltage) or a 4.5V, now it's time to rotate the motor until you get a change in the signal like this video. IF you don't get any voltage shift (like it stays at zero) make sure that your meter tip is touching the wire. If it stays at 4.5V then you likely have found the issue. Repeat with the 2 other colours make sure they all switch from 0 to 4.5V each 4-5 motor notches. If you have any signal that does not move up and down then one sensor is bad. IF you turn the throttle and let the motor run you will see a 2.5V average voltage coming from it (your meter is not fast enough to pickup the alternating voltage (0-4.5-0V...)

                  Now if you get a good signal coming off all 3 hall sensors and you still have the error 6 or getting that jerking issue then it's likely the controller that is damaged or that the magnetic disk on the motor shaft has moved, if it's the case click below to be redirected to the Hall sensor magnet adjustment link

                  Hall sensor magnet adjustment link


                  Additional info:

                  PS: there is a 6th wire , the white one. It's the positive coefficient temperature sensor. meaning the resistance goes up as the motor heats up and goes down when it cools off! If this wire is shorted to ground then the controller will think the motor is cool, unplug it and the controller will think it overheated it will stop the motor and throw error 10 or 11. To bypass it you just need to short the wire wire to the black on the controller side

                  Click image for larger version  Name:	fetch?id=104340&d=1587148206.jpg Views:	2447 Size:	806.1 KB ID:	116046

                  Support notes: Now this motor is weather proof but not submersible and crossing a deep river is not a good idea, so if water (especially salt water) finds it way through cable sheathing or sucked through an oring because of a rapid change in temperature (like a hot motor dipped in cool water) then it can ruin the hall sensors. This would not be covered under warranty.

                  Click image for larger version  Name:	IMG_2441.jpg Views:	0 Size:	443.7 KB ID:	116045

                  So you can remove the hall sensor cover and add some gasket maker to seal the cover off and also add some on the metal cable gland were the hall sensor wires get in, as you can see there is a second pair of wires next to the multi wire cable (the temp sensor) and the will leave a gap for water to get in even if the cable gland is tight. For this I had to cut away the nylon braid and will seal it with liquid electrical tape near the cable gland but I will also have seal were the 5 hall sensor wires enter the grey sheath.

                  Click image for larger version  Name:	IMG_2478.JPG Views:	2856 Size:	862.4 KB ID:	104339Click image for larger version  Name:	IMG_2477.JPG Views:	2892 Size:	806.1 KB ID:	104340
                  Attached Files
                  Last edited by Sebz; 12-10-2020, 02:48 PM.


                    Throttle problems

                    If you think you have throttle problems first step would be to check the error codes with the LED programing adapter (or called error code adapter) and see if you have any error codes, put the bike on a bench and give it a few throttle twist until you experience the problem you've been having. Could be error 14 , error 15 or no error code.

                    If in any case the motor when to full throttle without even touching the throttle then open a support ticket asap

                    Error 15 and error 14 could mean there is a problem with the wiring, possibly a wire got pulled out (ripped from the little circuit board inside the throttle body. IT could means the wires in the main harness are crushed and touching or can mean the controller has a problem.

                    The first step would be to replace the throttle with a new one, or test the signal:

                    SR throttle test

                    You have 3 wires going to it. So remove the bash guard to expose the throttle connection, it's a triangle shaped 3 pin connector that is inside the rubber black boot, locate the 3 wires. red black and green (they all have a white stripe on the wires). Leave the throttle connected. put the rear up in the air or remove the chain to be safe

                    Click image for larger version  Name:	IMG_3054.JPG Views:	0 Size:	748.1 KB ID:	115274

                    When powered you should have between 4.2V to 5VDC between the red and black

                    You should have 0.85V between the black and the green (throttle at rest)

                    And 3.6V at full throttle between the green and black.

                    You will have to poke thought the insulation of the wires if your probes are too big to fit the back of the connector.

                    SO if your issue is not intermittent and you have the right voltage range then it's likely not throttle related. Might be be the controller...

                    Replacing the throttle

                    There are 2 model , the mechanical throttle and the electronic throttle. Pre 2020 bikes came with the mechnical unit and the 2020 bikes now have the electronics one.

                    The mechanical throttle is a 3 parts system, the speed controller, the cable and twist handle and the metal body. We only have the 2 first parts, so please keep this in mind if you want to convert from a E-throttle to a mechanical one.


                    The E-throttle is a complete plug and play unit, if you have the mechanical throttle you can convert to the E-throttle


                    IF by any chance you cannot find the needed replacement part you can always convert your Sur-ron to an aftermarket throttle!

                    The Sur-ron uses a 3 wire hall sensor based throttle so basically the option are endless, you can pick any throttle we have in stock and convert it to your Sur-Ron

                    Please watch he video below, I will explain how to use any electronic throttle on your bike

                    NOTE: before cutting and splicing anything make sure to remove the battery and then let the controller capacitors drain (you just need to flip the breaker and ignition on without a battery attached)

                    The click version were I only show you the pinout of the throttle connector.

                    Testing the aftermarket throttle

                    Last edited by Sebz; 10-05-2020, 11:37 AM.