Speed Queen Washer Error Code Eio 33: Mosfet Enable Hardware
Eio 33 on a CHM1792C washer-extractor is a hardware failure of the Mosfet enable circuit on the input and output board. Where Eio 29 reports the control's pin, this code reports the circuit itself, so the board cannot safely drive valves, locks or the drive and the machine stops. Write down the code, wait for the door lock, and ask for service.
High: the board cannot safely drive its outputs, and the machine will not run until it is repaired.
- Code
- Eio 33
- Maker
- Speed Queen
- Equipment
- Washers
- Applies to
- CHM1792C family washer-extractor (QN models, 20-100 lb) front-end control
What does Speed Queen error code Eio 33 mean?
The enable circuit on the input and output board is the gate that lets the board's outputs switch on at all. A Mosfet inside it does that job, and the control checks the circuit as part of the board's self-test. Eio 33 reports that the circuit itself failed in hardware. That is different from Eio 29, which reports a problem seen at the control's enable pin: here the board's own circuit is the one that did not pass. Without a working enable circuit the board cannot safely drive the valves, the door lock or the motor drive, so the control stops the machine and the code stays on the display. The manual lists the input and output board enable circuit, the board connectors and supply, and whether a recent surge or power event occurred. A storm or a utility flicker shortly before the code is a useful clue to pass on.
Affected models and control systems
CHM1792C family washer-extractors, QN models, 20 to 100 lb, with the front-end control and its input and output board.
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 machine stops with Eio 33 shown
- No valves open and no cycle can start
- The code returns after the power is cycled
Possible causes
Listed in Speed Queen's documentation
- Input and output board enable circuit
- Board connectors and supply
- Whether a recent surge or power event occurred
Other likely causes — what usually sits behind error code Eio 33 on this control. A technician confirms which one it is before any part is replaced.
- A Mosfet damaged by a lightning storm or a switching surge on the building supply
- A board corroded by steam and detergent vapor in a closed laundry room
Safe checks before calling for service
- Write down the full code, Eio and its two digits.
- Wait until the door lock releases.
- If you can, leave the machine powered off with a sign on it.
- Request service and mention any recent power event.
How a technician diagnoses error code Eio 33
- Read the full code and confirm it returns after a power cycle.
- Ask about storms, outages or breaker trips before the code appeared.
- Check the supply voltage and the board connectors with power off and locked out.
- Compare the readings with the enable-related codes Eio 29, 38 and 39.
- Replace the input and output board once the supply and connectors are proven.
- The board carries live 208-240 V loads, so a surge-damaged unit is a shock hazard.
- A hardware failure in the enable circuit means the board needs replacement, not adjustment.
- Checking for surge damage requires meter work with the machine locked out.
How error code Eio 33 differs from similar codes
Eio 33 is the enable circuit hardware. Eio 29 is the enable pin, Eio 38 is an enable that cannot be turned on, and Eio 39 is one that cannot be turned off.
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 Speed Queen washer error codes
What is the difference between Eio 29 and Eio 33?
Eio 29 reports the control's enable pin. Eio 33 reports the enable circuit on the board itself.
Could a power surge have caused it?
Yes, the manual asks about a recent surge or power event, so mention one when you call.
Will powering off clear Eio 33?
Not for long. A hardware failure comes back until the board is repaired.
Need help with Speed Queen error code Eio 33?
A technician confirms the cause on site and gives you the price in writing before any work starts.