UniMac Washer-Extractor Error Code Eio 35: Lock Solenoid Output
Eio 35 is an I/O board hardware code for the door lock solenoid output. The board cannot reliably power the lock, so the control ends the cycle and the washer should not be used. Power down and call us for a test.
High: the board cannot reliably power the door lock, so the washer should not be used.
- Code
- Eio 35
- Maker
- UniMac
- Equipment
- Industrial laundry
- Applies to
- CHM1792C family washer-extractor (QN models, 20-100 lb) front-end control
What does UniMac error code Eio 35 mean?
Eio 35 is an input and output board hardware code on a UniMac QN washer-extractor for the door lock solenoid hardware output. This is the output stage that actually drives the lock solenoid, the last part of the circuit that the pin and relay checks lead to. The stage failed its check, so the board cannot reliably power the lock. The control ends the cycle and keeps the code until the board has been serviced, and the washer should not be used meanwhile. A door that cannot be locked on command could swing open when the drum is turning. The manual lists the board output stage for the lock solenoid, solenoid coil resistance and wiring, the connector at the lock, and whether a new I/O board is warranted. Noting whether the door latched helps us decide where to begin. Keep wet items away from the cabinet, leave the lock alone and wait for the drum to stop before anyone approaches.
Affected models and control systems
This applies to the CHM1792C family of UniMac QN washer-extractors, 20 to 100 lb, front-end control, for example the UCA020QN. Eio 35 is one of the lock-related hardware codes.
Code numbers and their meaning can change between control generations. We match the full model and control before acting on a code.
What you may notice
- Eio 35 on the display and the cycle stopped
- Door that may not latch when the cycle should start
- Weak or missing clicking from the lock
- Code that returns at the next start
Possible causes
Listed in UniMac's documentation
- Board output stage for the lock solenoid
- Solenoid coil resistance and wiring
- Connector at the lock
- Whether a new I/O board is warranted
Other likely causes — what usually sits behind error code Eio 35 on this control. A technician confirms which one it is before any part is replaced.
- A solenoid coil that has changed resistance with age and overloads the output stage
- A corroded lock connector adding resistance to the output
- A board output transistor damaged by voltage spikes from the lock coil
Safe checks before calling for service
- Record Eio 35 and note whether the door latched.
- Power the machine down and wait for the drum to stop.
- Leave the lock and cabinet alone.
- Call us for a test of the lock output, and keep wet items away from the cabinet.
How a technician diagnoses error code Eio 35
- Read the code and check whether the lock actuates when commanded.
- With power locked out, measure the solenoid coil resistance and inspect the connector.
- Check the harness for damage or chafing.
- Test the output stage of the I/O board against the maker's specification.
- Replace the solenoid or board once the failed part is identified.
- Testing a lock output stage requires live control voltage on the board.
- A door lock that fails to engage is a protective interlock problem, so repairs follow the maker's tests.
- Solenoid and board failures look similar from outside and need meter readings to separate.
Technical reference
- Document
- Washer-Extractor Programming CHM1792C_SVG, Part No. F8641001ENR4, Error Codes Table 29 (pp. 100-107)
- Maker documentation
- UniMac owner support
- Edition
- Part No. F8641001ENR4, January 2020
- Models / control
- CHM1792C family washer-extractor (QN models, 20-100 lb) front-end control
- Section
- Error Codes, Table 29, pp. 100-108 (PDF pages equal printed pages)
- Checked
- October 2026
We use the maker's document to read the code and do not reproduce it. Always confirm the complete model and control before applying these steps.
Related UniMac industrial laundry error codes
Can I run the washer with the door pressed shut?
No. A door held shut by hand is not locked, and the control will not run for that reason.
Does the coil matter?
Yes. A coil with the wrong resistance can overload the output stage.
Is Eio 35 related to Eio 32?
Both involve the lock circuit. Eio 32 is the relay pin. Eio 35 is the solenoid output stage.
Need help with UniMac error code Eio 35?
A technician confirms the cause on site and gives you the price in writing before any work starts.