Product Vend Mechanical Diagnostic Flow
USI 3502
Product Vend Mechanical Diagnostic Flow
Isolation of mechanical and electrical faults when a selection fails to deliver product.
Qualified technician handoff: stop before live electrical testing, sealed-system refrigeration work, compressor service, or protected-compartment access unless a qualified technician is handling the work.
- Motor smoke or burning smell during vend: Immediately discontinue vend attempts. Motor may have failed electrically. Do not apply power to that motor circuit.
- Multiple selections failing simultaneously: Likely a common cause such as controller issue or main harness problem rather than individual motor failures.
Checklist
Guided Diagnostic Steps
Work from low-risk checks toward technician-level inspection only when evidence supports it.
You can read or print the route now. The first checkbox click opens the service contact gate.
- 1
Check Internal Fuse or Breaker
operator-intermediatehighWith the machine unplugged locate the main fuse or circuit breaker on the power input or power supply assembly. Inspect for a blown fuse or tripped breaker. If a fuse is blown do not replace it until the cause is investigated. If a breaker is tripped reset it once and observe.
Digital MultimeterStop conditions- Fuse blows again immediately after replacement
- Breaker trips again immediately
Expected: Fuse is intact or breaker is in the on position.
Evidence to note: photo
Tools for this route
Location Help
Where to find this
Use this as orientation before touching the machine. It is location help, not a repair instruction.
Start at the customer delivery bin and product drop path; clear visible product and debris before moving to internal checks.
- Physically drives product from storage to delivery area when commanded by controller.
- Vend motors per selection
- Motor harness connectors
- Drive mechanisms such as coils or paddles
Do not open energized or protected electrical areas unless a qualified technician or licensed electrician is handling the work.
cabinet generic
control board generic
wiring harness
display keypadParts status
Exact public parts list not verified yet. Use this route to identify the system before ordering.
Candidate areas for part verification
Other Possible Issues
Switch routes if this symptom is not the closest match.