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EZBv4 Disconnects on RGB Enable

Ezbv4 Disconnects On RGB Enable

My EZBv4 disconnects immediately when I connect or enable the RGB LED. I already tried flipping the cable 180 but that didn't help.

I'm running ARC and I noticed the EZB temperature shown in ARC is higher when the RGB is connected. In the EZB status it shows 30 and 21 (not sure why there are two values) when the RGB is connected, and about 29 when the RGB is disconnected.

dontstayconncted.jpg

Any ideas?



Related Hardware (view all EZB hardware)
EZ-B V4 by EZ-Robot
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Servos 24
Camera
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UART 3
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ADC 8
Digital 24

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Connects EZ-B I/O controllers to ARC via COM or IP (5 connections). Supports init scripts, battery monitoring, TCP/EZ-Script server and serial/I2C.
Debug by Synthiam
Central ARC debug window routing logs; shows UTC date/time, Windows/ARC/skill/hardware info, version/settings, with copy and clear.

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Author Avatar
PRO
Canada
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#1  

It sounds like the RGB Eyes / RGB LED cable or device is causing a power or communication issue, and the fact that ARC disconnects immediately when it’s enabled points more toward a wiring, short, or device fault than a normal temperature issue.

A few notes from what you described:

  • Flipping the cable 180 didn’t help, so it may not just be orientation.

  • The temperature changing by 1-2C is usually not enough to cause a disconnect.

  • The "30 and 21" you’re seeing is likely two different readings in the status area, usually something like:

    • CPU temperature
    • Battery voltage

    If you want, I can help you identify exactly what those numbers are from the screenshot.

What to check first

1) Inspect the RGB cable and port

  • Look for bent pins, damaged wire insulation, or a loose connector.
  • Reseat both ends firmly.
  • Try a different port if the RGB hardware supports it.

2) Test with the RGB disconnected

  • If ARC stays connected with RGB unplugged, that strongly suggests:
    • the RGB module may be faulty, or
    • the cable is shorted, or
    • the port/device is drawing too much current.

3) Check for a short or overload

A disconnect that happens the moment the RGB is enabled often means the EZ-B is hitting a fault condition. Even if the LED seems simple, a bad module or wiring can pull the board down.

4) Verify power supply stability

If the EZ-B is already running near the limit, adding the RGB could be enough to trigger a brownout/disconnect. This is especially common if servos or other loads are also powered from the EZ-B.

See the power/brownout info here:

About the temperature reading

A 1C increase is normal. The EZ-B v4 should not disconnect because of that small change. So I would focus on:

  • wiring
  • RGB module/cable condition
  • power supply capacity
  • whether the RGB hardware itself is defective

Best next test

Try this:

  1. Disconnect all other peripherals
  2. Connect only the EZ-B and RGB
  3. Enable the RGB
  4. See if it still disconnects

If it still drops immediately, the RGB hardware or cable is the most likely culprit.

If you want to dig deeper

Install the Debug skill in ARC and capture the log right before the disconnect:

That can help show whether ARC is losing the board due to communication, power, or a device response problem.

If you can, tell me:

  • what exact RGB hardware this is,
  • which port it’s plugged into,
  • whether the disconnect happens only when enabled or also just when connected,
  • and whether the robot is powered by battery or a wall supply.
I am a customer support AI and still learning. Please verify important answers in our support documentation. For advanced AI features, use the AI Script Agent built into ARC.
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PRO
Belgium
Thingiverse
#2  

@athena

can it be that the original number is change ( 0XA0 ) ? and that it disconnect the ezbv ?

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PRO
Canada
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#3  

Yes - if the RGB Eyes / RGB Animator I2C address was changed from the default 0xA0, ARC may be trying to talk to the wrong device address.

That said, a wrong I2C address by itself usually should not disconnect the EZ-B v4. It would more commonly cause:

  • the RGB skill not to work
  • the skill to hang while waiting for the device
  • ARC to appear frozen or unresponsive if the I2C device never responds

What I would do

1) Check the RGB Animator settings

Open the skill’s kebab menu (three lines in the top-right of the skill) and verify:

  • I2C Address
  • the skill is set to the correct EZ-B board index
  • no other skill is using the same I2C device/address

If the address was changed previously, set it back to:

0xA0

2) Test with only the RGB skill loaded

Temporarily remove or disable other I2C-related skills and test again.
A conflict on the I2C bus can cause issues.

3) If the address was changed and you’re not sure what it is

You’ll need to rediscover the address on the I2C bus, then change it back in the skill. The RGB Animator docs mention this behavior:

4) If it still disconnects immediately

Then the problem is more likely:

  • a shorted cable
  • a bad RGB board
  • power instability
  • or an I2C bus lockup

Important note

If this is the original EZ-Robot RGB Eyes / JD eyes hardware, the default address is indeed 0xA0. If it was modified, ARC will only work if the skill matches that new address.

Quick question

Did you change the RGB address manually at some point, or is this a brand-new setup that’s never been configured before?

If you want, I can also walk you through how to verify the I2C address in ARC step by step.

I am a customer support AI and still learning. Please verify important answers in our support documentation. For advanced AI features, use the AI Script Agent built into ARC.
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PRO
Synthiam
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#4  

Yes, an invalid address or poor connected cable or broken solder joint to a plug on the cable will cause the ezb to disconnect when talking to i2c

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PRO
Canada
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#6  

You're welcome - glad we narrowed it down.

That points very strongly to one of these:

  • Wrong I2C address
  • Loose/damaged cable
  • Broken solder joint or intermittent connection
  • A device on the I2C bus holding the line low

If you want to verify it quickly in ARC, check the RGB Animator skill settings from the kebab menu and confirm the I2C address is still 0xA0. If it was changed, set it back and test again.

If the address is correct and it still disconnects, then I’d inspect:

  1. The cable ends
  2. The connector pins
  3. The solder joints on the RGB board
  4. Whether the EZ-B stays connected with the RGB unplugged

You can also use the Debug skill in ARC to capture the exact moment it disconnects.

If you’d like, I can help you do a quick I2C isolation test in ARC to tell whether it’s the address or the hardware.

I am a customer support AI and still learning. Please verify important answers in our support documentation. For advanced AI features, use the AI Script Agent built into ARC.
Author Avatar
PRO
Canada
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#8  

Thanks for testing that - the videos are very helpful.

If the same RGB hardware works on the IoTiny but causes the EZ-B v4 to disconnect, that strongly suggests the issue is with the EZ-B v4 I2C side, not the RGB board itself.

What that usually means

Most likely possibilities:

  • I2C bus on the EZ-B v4 is being pulled down or shorted
  • A damaged connector or solder joint on the v4 I2C pins
  • The v4’s lower I/O board is partially damaged
  • Power/ground instability on the v4 when the I2C device is connected

Since the IoTiny behaves normally with the same RGB device, the RGB hardware is probably okay.

What to test next

1) Try a different I2C device on the EZ-B v4

If you have another I2C sensor or module, test it on the v4.

  • If all I2C devices disconnect the v4, the v4 I2C interface is likely the problem.
  • If only the RGB device causes it, then the RGB cable or address is still suspect.

2) Check the v4 I2C wiring and port

Inspect:

  • bent pins
  • loose connector
  • damaged cable
  • solder joint cracks
  • anything touching adjacent pins

3) Test the v4 with nothing else connected

Disconnect everything except:

  • EZ-B v4 power
  • ARC connection
  • the RGB device

If it still drops immediately, that’s a strong sign of a hardware fault on the v4 side.

4) Compare power sources

If the IoTiny test was on a different supply than the v4, compare:

  • battery voltage
  • current capability
  • whether the v4 is under load when the RGB is attached

Important observation

On the EZ-B v4, a startup sound or normal connection doesn’t always mean the I2C side is healthy. A board can appear mostly fine and still fail when an I2C device talks to it.

My conclusion

Based on your tests, I’d lean toward:

  • EZ-B v4 I2C hardware issue
  • or a damaged/unstable connection on the v4’s I2C bus

rather than the RGB unit itself.

If you want, I can help you do a step-by-step isolation test in ARC to confirm whether:

  1. the I2C bus is bad, or
  2. the board is only failing with this one device

If you’d like, I can also tell you how to check the EZ-B v4 status and logs so we can narrow it down further.

I am a customer support AI and still learning. Please verify important answers in our support documentation. For advanced AI features, use the AI Script Agent built into ARC.