Emojo Wildcat 500w LED Display Flashing

[gilg90]

Hey everyone, I just picked up my first e-bike after coming from the e-skate world. I bought an Emojo Wildcat 500W for $80. It didn’t turn on and didn’t come with a charger, but it did come with a fully charged battery.


I managed to get the LED display to power on, but when I use the throttle nothing happens. If I try to pedal and give it throttle, still nothing. After about 2–3 minutes, the display starts flashing — it flashes exactly 20 times.


The controller wiring was a mess, and I had to cut off some random add-on wiring the previous owner installed. Now I can’t tell if the hub motor is blown, or if it’s just a controller issue. If it’s the controller, I don’t mind buying a new one and swapping things out.


This bike is from around 2016, and I’m having a really hard time finding any documentation on it — manuals, controller info, wiring diagrams, anything. I did order a charger; it should arrive in a day or two.


TL;DR: Bike powers on, display works, but throttle and pedal assist do nothing. Display flashes 20 times after a couple minutes. Not sure if it’s a sensor issue, controller issue, or a dead motor. Any info on the Emojo Wildcat 500W (around 2016) would really help.

 

[HumanPerson]

Heya man Welcome to the forums!

 

[HumanPerson]

I'm not sure of your situation in life but it might be better to just go ahead and swap out that controller and display for new ones.
While you are disassembling, just look for flaws in the connections and what not.

Have ya tested the battery too..like with a multimeter to see what voltage it is at now?

 

[Annieolnie]

https://device.report/emojo. This site won't link. One of the things they mention is to check you brake motor cutoffs if the display is flashing. See if you have plugs near the brake cables.
This site has a pdf near the bottom for the older bikes. Basically it's just type written instructions, see if any of them help. Wait, retrospectively, I think it did link.

 

[usclassic]

From Grok

Overview of the Emojo Wildcat 500W Electric Bike (circa 2016)The Emojo Wildcat 500W is a fat-tire electric mountain bike (e-MTB) designed for versatile off-road and urban use. Released around 2016-2017, it was marketed as an affordable, rugged option for trails, dirt paths, pavement, and parks, with a focus on lightweight construction and reliable performance. It's part of Emojo's early lineup of e-bikes, emphasizing fun and accessibility for beginners and adventure riders. Original retail prices hovered around $1,100–$1,200, often bundled with free shipping and accessories like fenders. Today, used models (like yours) can be found for as low as $80 on secondary markets, but parts and documentation are scarce due to its age.Key SpecificationsHere's a breakdown of the core specs based on 2016-2017 models:

[th]Feature[/th]
[th]Details[/th] [td]Motor[/td]
[td]48V 500W Bafang rear hub (DC brushless, 85-90% efficiency; torquey for hills, quiet operation)[/td] [td]Battery[/td]
[td]48V 10.4Ah lithium-ion (removable; ~25-30 miles range per charge, depending on terrain/load)[/td] [td]Top Speed[/td]
[td]20 mph (street-legal limit)[/td] [td]Charging Time[/td]
[td]4-6 hours[/td] [td]Frame[/td]
[td]Lightweight aluminum alloy rigid frame (dimensions: ~78"L x 25"W x 43"H)[/td] [td]Tires[/td]
[td]26" x 4.0" fat tires (Kenda; excellent for sand, gravel, snow)[/td] [td]Gearing/Drivetrain[/td]
[td]Shimano 7-speed[/td] [td]Brakes[/td]
[td]Tektro mechanical disc brakes (front/rear; some later variants had hydraulic upgrades)[/td] [td]Display[/td]
[td]Basic LED/LCD (shows speed, battery level, assist mode; 3 pedal-assist levels + throttle)[/td] [td]Weight Capacity[/td]
[td]250 lbs[/td] [td]Weight[/td]
[td]~55-60 lbs (bike only)[/td] [td]Other Features[/td]
[td]Pedal-assist (PAS) system, throttle, LED lights (optional), kickstand[/td]

This setup makes it a solid entry-level e-MTB—powerful enough for moderate trails but not overly complex for daily commuting.Reviews and User FeedbackContemporary reviews from 2016-2018 highlight its value as a budget-friendly fat-tire e-bike. On sites like Ride Review and Amazon, it scores around 4/5 stars for off-road capability and ease of use. Users praised:

• Performance: The Bafang motor delivers strong torque for steep inclines, with smooth throttle response. One reviewer called it "a beast on trails" that "flattens hills."
  
• Build Quality: The alloy frame feels "solid and rugged," and the fat tires handle rough terrain well without feeling bulky.
  
  It's quieter and more efficient than cheaper hub motors.
• Value: At the time, it was lauded as "one of the most affordable and impressive electric mountain bikes for the price," outperforming some competitors like early Rad Rovers on torque and weight.
  
  [th][/th]
  [th][/th] [td][/td]
  [td][/td] [td][/td]
  [td][/td] [td][/td]
  [td][/td] [td][/td]
  [td][/td] [td][/td]
  [td][/td] [td][/td]
  [td][/td]

Troubleshooting Your Issue (LED Flashing 20x, No Throttle/PAS)Your symptoms—power-on but no motor response, followed by 20 LED flashes—point to a common error code on Bafang-equipped e-bikes from that era. Based on similar reports:

• Likely Cause: The 20-flash code often indicates a throttle or PAS sensor fault (e.g., loose connection, faulty hall sensor in the motor, or controller error). It could also be a low-voltage cutoff if the battery (even if "fully charged") has degraded cells—9-year-old lithium batteries commonly hold only 50-70% capacity and trigger protections. Less likely: a dead motor winding or main controller failure.
• Quick Checks:
  
  1. Inspect wiring: Unplug/replug the throttle, PAS sensor (at crank), and display connectors. Look for corrosion or fraying—common on 2016 models exposed to moisture.
  2. Test battery: Use a multimeter on the main leads (should read ~48-54V fully charged). If under 40V, it's toast.
  3. Reset: Power cycle (off for 5 mins), or hold the power button + up/down arrows on the display for a soft reset.
• Next Steps: Once your charger arrives, fully charge and retest. If no luck, the controller (often a basic 48V 15-20A unit) or throttle (~$20-30 replacement) are cheap fixes. Manuals are rare, but generic Bafang wiring diagrams are available online (search "Bafang BBS01 error codes"—yours uses a similar hub system). Local e-bike shops familiar with Bafang can diagnose for $50-100; avoid standard bike mechanics, as e-bike electronics aren't universal.

Emojo's warranty (2 years originally) is long expired, but you can email support@emojo.com or check electricbikesforall.com for archived docs—they handle legacy Emojo queries. If it's a sensor issue, you could be riding for under $50 in parts. Great score at $80—sounds like a fun project bike! If you share more details (e.g., photos of the display/wiring),


Welcome to the forum.

 

[Annieolnie]

Either someone just made a whole lot of touch downs, or I have no idea what a any of that is suppose to mean.

 

[gilg90]

ook since i have posted about this bike i have found some pretty frightening things
1. the controller wiring wahs chewed up by the sprockets and chain so i managed to fix that.
2. the wiring in the motor was messed with it looks like they tried to swap out the cable for a new one but all they did was make a mess nothing looked like it crossed or burned anything.
3i testes the hall sensors they all seem to be working
4. i tested the motor to see if the windings were ruined and all check out no opens or shorts.
5. testing the voltage to the motor fr the hall sensors throught the controller was strange it started at 5.6v then when the screen would start flashing it would drop down to 2v.
6. the pas sensor is there i could get resistance but im not sure if the disk should have magnets i know the new ones do.
7. i have bought the charger for the battery i cannot find a mfg date on it (assuming @usclassic is correct then there may be an isse ther i do get 53.6v)




id like to thank you all for the help

 

[gilg90]

I'm not sure of your situation in life but it might be better to just go ahead and swap out that controller and display for new ones.
While you are disassembling, just look for flaws in the connections and what not.

Have ya tested the battery too..like with a multimeter to see what voltage it is at now?

i have done that tonight i should be getting the new controller tomorrow

amazon.com/gp/product/B0DB8HRHJ2/ref=ox_sc_act_title_5?smid=A1QNE4QY7A5FUS&psc=1

 

[gilg90]

https://device.report/emojo. This site won't link. One of the things they mention is to check you brake motor cutoffs if the display is flashing. See if you have plugs near the brake cables.
This site has a pdf near the bottom for the older bikes. Basically it's just type written instructions, see if any of them help. Wait, retrospectively, I think it did link.
View attachment 23176View attachment 23177

no plugs i will be buying some in the near future. i just bough a new controller and it has the wiring for them.

 

[gilg90]

From Grok

Overview of the Emojo Wildcat 500W Electric Bike (circa 2016)The Emojo Wildcat 500W is a fat-tire electric mountain bike (e-MTB) designed for versatile off-road and urban use. Released around 2016-2017, it was marketed as an affordable, rugged option for trails, dirt paths, pavement, and parks, with a focus on lightweight construction and reliable performance. It's part of Emojo's early lineup of e-bikes, emphasizing fun and accessibility for beginners and adventure riders. Original retail prices hovered around $1,100–$1,200, often bundled with free shipping and accessories like fenders. Today, used models (like yours) can be found for as low as $80 on secondary markets, but parts and documentation are scarce due to its age.Key SpecificationsHere's a breakdown of the core specs based on 2016-2017 models:

[th]Feature[/th]
[th]Details[/th] [td]Motor[/td]
[td]48V 500W Bafang rear hub (DC brushless, 85-90% efficiency; torquey for hills, quiet operation)[/td] [td]Battery[/td]
[td]48V 10.4Ah lithium-ion (removable; ~25-30 miles range per charge, depending on terrain/load)[/td] [td]Top Speed[/td]
[td]20 mph (street-legal limit)[/td] [td]Charging Time[/td]
[td]4-6 hours[/td] [td]Frame[/td]
[td]Lightweight aluminum alloy rigid frame (dimensions: ~78"L x 25"W x 43"H)[/td] [td]Tires[/td]
[td]26" x 4.0" fat tires (Kenda; excellent for sand, gravel, snow)[/td] [td]Gearing/Drivetrain[/td]
[td]Shimano 7-speed[/td] [td]Brakes[/td]
[td]Tektro mechanical disc brakes (front/rear; some later variants had hydraulic upgrades)[/td] [td]Display[/td]
[td]Basic LED/LCD (shows speed, battery level, assist mode; 3 pedal-assist levels + throttle)[/td] [td]Weight Capacity[/td]
[td]250 lbs[/td] [td]Weight[/td]
[td]~55-60 lbs (bike only)[/td] [td]Other Features[/td]
[td]Pedal-assist (PAS) system, throttle, LED lights (optional), kickstand[/td]
This setup makes it a solid entry-level e-MTB—powerful enough for moderate trails but not overly complex for daily commuting.Reviews and User FeedbackContemporary reviews from 2016-2018 highlight its value as a budget-friendly fat-tire e-bike. On sites like Ride Review and Amazon, it scores around 4/5 stars for off-road capability and ease of use. Users praised:

• Performance: The Bafang motor delivers strong torque for steep inclines, with smooth throttle response. One reviewer called it "a beast on trails" that "flattens hills."
• Build Quality: The alloy frame feels "solid and rugged," and the fat tires handle rough terrain well without feeling bulky.
  
  It's quieter and more efficient than cheaper hub motors.
• Value: At the time, it was lauded as "one of the most affordable and impressive electric mountain bikes for the price," outperforming some competitors like early Rad Rovers on torque and weight.
  [th][/th]
  [th][/th] [td][/td]
  [td][/td] [td][/td]
  [td][/td] [td][/td]
  [td][/td] [td][/td]
  [td][/td] [td][/td]
  [td][/td] [td][/td]
  [td][/td]

Troubleshooting Your Issue (LED Flashing 20x, No Throttle/PAS)Your symptoms—power-on but no motor response, followed by 20 LED flashes—point to a common error code on Bafang-equipped e-bikes from that era. Based on similar reports:

• Likely Cause: The 20-flash code often indicates a throttle or PAS sensor fault (e.g., loose connection, faulty hall sensor in the motor, or controller error). It could also be a low-voltage cutoff if the battery (even if "fully charged") has degraded cells—9-year-old lithium batteries commonly hold only 50-70% capacity and trigger protections. Less likely: a dead motor winding or main controller failure.
  1. Inspect wiring: Unplug/replug the throttle, PAS sensor (at crank), and display connectors. Look for corrosion or fraying—common on 2016 models exposed to moisture.
  2. Test battery: Use a multimeter on the main leads (should read ~48-54V fully charged). If under 40V, it's toast.
  3. Reset: Power cycle (off for 5 mins), or hold the power button + up/down arrows on the display for a soft reset.
• Next Steps: Once your charger arrives, fully charge and retest. If no luck, the controller (often a basic 48V 15-20A unit) or throttle (~$20-30 replacement) are cheap fixes. Manuals are rare, but generic Bafang wiring diagrams are available online (search "Bafang BBS01 error codes"—yours uses a similar hub system). Local e-bike shops familiar with Bafang can diagnose for $50-100; avoid standard bike mechanics, as e-bike electronics aren't universal.

Emojo's warranty (2 years originally) is long expired, but you can email support@emojo.com or check electricbikesforall.com for archived docs—they handle legacy Emojo queries. If it's a sensor issue, you could be riding for under $50 in parts. Great score at $80—sounds like a fun project bike! If you share more details (e.g., photos of the display/wiring),


Welcome to the forum.

ha.. i didnt grok and i should have obviously. i chat gpt'd not near this clear info about the bike. yea i found some parts i found a used but working hub for $50 im gonna pick it up payday. even if mine works i will keep it as back up.

 

[gilg90]

i had kapton tape because i ran out of electrical tape.. to wrap the bundles of wire. my work is the shrink tube stuff..

 

[gilg90]

now a question. i was wondering if upgrading this up to a 750x 1000w bike would make it faster.. im not sure if the bafang, makes a 750 and up fat tire hub.. would it be worth the trouble or should i just save for a a bike that can do that already..

 

[Annieolnie]

Your link to the controller wouldn't work. Did you buy one with its own display? They usually have to be matched, unless you bought the exact same model from the ebike maker. Bafang makes seven fifties. The picture below is from Aliexpress. Be careful with which motor plug it has. Different runs of motors have different plugs. Adapters are available, but it is better to find the adapter before you commit.

 

[gilg90]

Your link to the controller wouldn't work. Did you buy one with its own display? They usually have to be matched, unless you bought the exact same model from the ebike maker. Bafang makes seven fifties. The picture below is from Aliexpress. Be careful with which motor plug it has. Different runs of motors have different plugs. Adapters are available, but it is better to find the adapter before you commit.
View attachment 23202

I did buy one with its own display
https://a.co/d/as7jTEc
Oh nice they do have a750w

 

[gilg90]

update if anyone is interested.. the motor works... the new controller works... the old one was spent.. the bike is fast i have to adjust the settings. but i now own a fully functional ebike i just need lights...

thank you everyone for your help and suggestions i appreciate it all ill post vids and pics of it running on friday ..