RadCity (2016-2020) error 30 / connector check guide

To troubleshoot an error 30 (communication error) on a RadCity, perform a connector check to ensure all connectors are secure and in good condition.

This guide uses a 2016 RadCity but the steps will be the same for other RadCity models that use an LCD display, i.e., RadCity 2/RadCity ST 1 (2018), RadCity 3/RadCity ST 2 (2019) and RadCity 4/RadCity ST 3 (2020). 

The RadCity 5 Plus error 30 / connector check guide is available HERE. 

Tools Needed:

• Flat side cutters
• Flat head screwdriver
• A camera
• Zip ties 

Note: The process for checking the connectors below will involve unplugging the connector, inspecting the inside for damage, plugging in the connector, and turning on the bike to check if the error persists while the connector is plugged in.

1. Get the bike ready for maintenance. Turn off the bike, remove the battery, and press MODE to discharge remaining power.
2. Check the battery and battery mounting tray terminal contacts. Visually inspect the terminal contacts. If they are in good condition, reinstall the battery and turn on the bike to check if the issue is resolved. If the bike will not turn on, remove the battery, discharge remaining power, and check the next connector.
3. Locate and unplug the connector, starting with the battery connector. Follow the cable from the part to the connector. Snip zip ties for easier access, then pull each side of the connector directly apart without twisting.
4. Inspect the inside of the connector. If the inside of the connector is wet, dirty, or damaged, take a photo and contact Product Support. If the connector looks normal, continue to the next step.
5. Plug in the connector. If the connector has no visible damage, line up the internal notch and pins (and external indicators) and press directly together without twisting.
6. Check if the error persists. Reinstall the battery, turn on the bike, and check if the error persists. If the error persists, continue to the next step.
7. Check the next connector. Turn off the bike, remove the battery, discharge remaining power, and check the next connector.

Repeat these steps with the three connectors listed below; the battery connector, display connector, and wiring harness connector.

Battery Connector

Location: Bottom bracket area

Color: Black inside

Check the connection between the battery and the controller. The battery connector is the large connector located near the bottom bracket. The connector is flat on one side and is black inside with two large prongs. Follow the steps below to check the connector.

   

Display Connector

Location: Handlebar area

Color: Black inside

Untwist the metal portion of the connector, then pull directly apart without twisting. To reconnect, align the internal notch and pins, and twist the metal portions until the connector is secure.

Wiring Harness Connector

Location: Near seat tube

Color: Black inside

To access the connector:

1. Turn the handlebar to the side to create cable slack.
2. Feed the wiring harness cable into the top of the downtube.
3. Remove the rubber grommet from the lower cable opening. At the bottom of the downtube, use a flat head screwdriver to carefully unseat the rubber grommet.
   
   
   
4. Access and inspect the connector. Gently pull out the wiring harness connector while feeding more cable into the top of the downtube. Once the connector is out of the downtube, unplug it, inspect the inside, and reconnect.
   
   
5. Insert the connector into the downtube. Carefully push the connector back into the downtube and reinstall the grommet.
6. Reinstall the battery and check if the issue is resolved.

Follow the steps below to check the remaining connectors.

Note: The process for checking the connectors below will involve unplugging the connector and turning on the bike to check if the error persists while the connector is still unplugged.

1. Get the bike ready for maintenance. Turn off the bike, remove the battery, and press MODE to discharge remaining power.
2. Locate and unplug the connector. Follow the cable from the part to the connector. Snip zip ties for easier access, then pull each side of the connector directly apart without twisting.
   
3. Inspect the inside of the connector. If the inside of the connector is wet, dirty, or damaged, take a photo and contact Product Support. If the connector looks normal, continue to the next step.
4. Check if the error persists with the connector unplugged. Leave the connector unplugged. Reinstall the battery, turn on the bike, and check if the error persists. If the error persists, continue to the next step.
   
   If the error is resolved when the connector is unplugged, the part may need to be replaced. Contact us for more help.
5. Turn off the bike and plug in the connector. If the error persists, turn off the bike, remove the battery, and discharge remaining power. If the connector has no visible damage, line up the internal notch and pins (and external indicators) and press directly together without twisting.
   
6. Repeat steps 1 through 5 on each connector listed below until the error is resolved. Once resolved, replace zip ties and trim to be flush and smooth. Test the bike fully and ride Rad!

Motor Connector

Location: Near the chainstay, on the left side of the bike

Color: Black inside

Taillight Connector (For Bikes 2019 and Later Only)

Location: Back of the bike

Color: Blue inside

  

Second Taillight Connector (For Bikes 2019 and Later Only)

Location: Near the seatstay

Color: Blue inside

This connector only exists on bikes that have a rear rack installed. Trace the cable from the first taillight connector to the connector plugged into the controller.

Brake Connectors

Location: Handlebar - left and right side

Color: Red inside

Check one brake connector, then test the bike to see if the issue is resolved. If not, check the other brake connector.

   

Throttle Connector

Location: Handlebar area

Color: Yellow inside

  

Headlight Connector

Location: Front of the bike

Color: Red inside

Pedal Assist (PAS) Sensor Connector

Location: Near the bottom bracket

Color: Yellow inside

    

 If you are not confident in your ability to safely and successfully perform all steps, we recommend having the work performed or checked by a local, certified, and reputable bike mechanic.