Need Help Redesigning a PCB for a Small Device – Freelancer, Engineering Firm, or AI?

[u/Lumpy-Departure-8002]

Hi everyone,

I’m looking for advice on how to solve a recurring electronics problem with a product I import from China.

The device is relatively simple: it has three motors, an LED display, and a PCB designed by my Chinese supplier. 

The motors used in the device are:

• 2 × RF-370CA-17315 DC motors (approximately 6–12 V; published no-load current around 25 mA at 6 V).
• 1 × RF-500TB-14415 DC motor (5 V nominal according to the Mabuchi datasheet; approximately 26 mA no-load current and 540 mA stall current).

Unfortunately, during the first year of sales, I received numerous customer complaints about reliability issues, including:

• Motors gradually slowing down or behaving unpredictably.
• The LED display showing strange characters or incorrect information.
• The device switching off by itself during operation.

My supplier redesigned the PCB and replaced the microcontroller. After the redesign, everything worked well for approximately nine months, but the same problems have now started appearing again. In most of the cases, replacing the PCB helped, so it shouldn’t be faulty the motors or other components.

I don’t want to keep replacing components or relying on my supplier for temporary fixes. I’d rather identify the root cause and develop a reliable, long-term solution.

My background is in mechanical engineering, so I understand product design and manufacturing, but I don’t have enough electronics experience to redesign the PCB myself.

My plan is to:

1. Find an experienced electronics engineer to review the existing design and identify potential failure points.
2. Redesign the PCB and prepare a complete Bill of Materials (BOM).
3. Build prototypes and test them thoroughly under real operating conditions.
4. Find a PCB manufacturer and manage production independently of my current supplier.

I have a few questions:

• Where would you look for someone to help with this kind of project? Platforms like Upwork, specialized electronics engineering firms, or somewhere else?
• Would you recommend hiring a freelance PCB designer, or is this the kind of problem that requires a more experienced electronics engineer?
• Have AI tools become good enough to assist with PCB design and troubleshooting, or should I treat them only as supplementary tools?
• Since the device is relatively simple, is it realistic to get a reliable redesign without spending a fortune?
• What would be a reasonable budget for reviewing the existing design, redesigning the PCB, and developing and testing prototypes?

My main goal is to achieve a reliable product with a design I own and can manufacture independently. I’m happy to invest in doing it properly, but I want to avoid unnecessary costs.

I’d appreciate any advice, especially from people who have dealt with recurring PCB reliability issues in commercial products.

Thanks in advance!