Huebsch QN Washer-Extractor Error Code Eio 31: Door Lock Pulse Pin
Eio 31 on a Huebsch QN washer-extractor means the pin that sends the pulse to the door lock solenoid failed its check on the input and output board. The control cannot be sure the door will lock or release, so it stops the machine.
High: the control cannot confirm the door lock, so the machine will not run.
What does Huebsch error code Eio 31 mean?
The door lock solenoid on a QN-series washer-extractor moves the lock with a short pulse of power. The input and output board creates that pulse through a dedicated pin, and the board tests the pin as part of its self-check. When Eio 31 appears, that test failed. The control cannot be sure the door will lock before a spin or release afterward, and it prefers to stop the machine rather than guess. Operators see a washer that refuses to start, or one that cannot finish a cycle. The board or the lock wiring is where we look first. The solenoid and its connector come next, followed by the supply to the board. Because the code comes from a self-test and not from a sensor reading, adjusting the wash program will not change it. A related code, Eio 36, reports the hardware test of the same pulse circuit.
Affected models and control systems
This applies to Huebsch QN-series washer-extractors in the CHM1792C family, 20 to 100 lb, with the front-end control in that programming manual.
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
- The washer refuses to start or finish a cycle and shows Eio 31
- The door may not latch or may stay locked
- The code returns after power is cycled
Possible causes
Listed in Huebsch's documentation
- Board's pulse output to the lock solenoid failing
- Solenoid and its harness damaged
- Connector fit at the board loose
- Power not reaching the board
Other likely causes — what usually sits behind error code Eio 31 on this control. A technician confirms which one it is before any part is replaced.
- A solenoid connector corroded by wash chemicals near the door frame
- A pulse driver weakened by repeated hard door closures
Safe checks before calling for service
- Switch off the machine and wait until the door lock releases.
- Check that the door is closed squarely, without forcing it.
- Restore power once and watch the display.
- Use the online form to book a visit if Eio 31 remains, and tell us whether the lock clicked.
How a technician diagnoses error code Eio 31
- Read the code and confirm Eio 31 returns after a power cycle.
- Inspect the lock solenoid, harness and connector for corrosion, heat or loose pins.
- Measure the solenoid resistance with the power locked off.
- Check the supply voltage and ground at the board.
- Replace the board or solenoid only after tests identify the failed part.
- The lock pulse is switched at mains-level voltage on the board, so testing it is live electrical work.
- The door lock protects people from the spinning basket, so its repair needs the maker's procedure.
- Separating a failed pulse driver from a damaged harness takes a meter and the wiring diagram.
How error code Eio 31 differs from similar codes
Eio 31 is the pulse-pin self-check. Eio 36 is the hardware test of the same pulse circuit, and Eio 30 is the disable pin.
Technical reference
- Document
- Washer-Extractor Programming CHM1792C_SVG, Part No. F8641001ENR4, Error Codes Table 29 (pp. 100-107)
- 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 Huebsch washer error codes
Why does the machine need a pulse for the lock?
The solenoid moves the lock with a short burst of power, so the board must be able to send it.
Can I run the machine with the door closed anyway?
No. The control will not run when it cannot confirm the lock.
Is Eio 31 the same as Eio 36?
No. Eio 31 is the pin check; Eio 36 is the hardware test.
Need help with Huebsch error code Eio 31?
A technician confirms the cause on site and gives you the price in writing before any work starts.