Speed Queen Washer Error Code Eio 38: Mosfet Cannot Be Enabled
Eio 38 means the Mosfet enable on a CHM1792C washer-extractor's input and output board cannot be turned on. The board tried to switch the enable line on and it did not respond, so valves, the lock and the drive cannot work. Note the code, let the door lock release, leave a sign, and contact us.
High: the outputs cannot be enabled, so the machine cannot start a cycle until it is repaired.
- Code
- Eio 38
- 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 38 mean?
The Mosfet enable is the gate that lets the input and output board's outputs switch on. At start-up, the control asks the board to turn that gate on and then checks that it did. Eio 38 means the enable line did not respond to that request: it stayed off. With the enable stuck off, none of the board's outputs for valves, the lock or the drive can work, so the machine cannot start a cycle and the code stays on the display. This is the opposite problem to Eio 39, where the line will not turn off. The manual lists the enable circuit on the board, the board supply and connectors, and the control signal to the board. A missing signal from the control to the board produces the same result as a dead enable circuit, so a technician tests the signal before condemning the board. The machine itself is not damaged by the code.
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
- Eio 38 appears at start-up and nothing runs
- No valves open and the drum does not turn
- The code returns on every restart
Possible causes
Listed in Speed Queen's documentation
- Enable circuit on the board
- Board supply and connectors
- Control signal to the board
Other likely causes — what usually sits behind error code Eio 38 on this control. A technician confirms which one it is before any part is replaced.
- A ribbon or harness between the control and the board that is seated crooked
- A power supply on the board that sags before the enable line can rise
Safe checks before calling for service
- Copy the code exactly, Eio plus both digits.
- Let the door lock release before anyone touches the door.
- Leave a sign on the machine so customers do not use it.
- Do not open the cabinet; contact us for service.
How a technician diagnoses error code Eio 38
- Read the full code and confirm it returns on a restart.
- Check the harness between the control and the board for seating and damage, with power off.
- Measure the board supply at start-up.
- Confirm the control sends the enable signal.
- Measure the enable line response.
- Replace the board or control only after the signal and supply are proven.
- The board feeds live 208-240 V loads, so probing the enable line is a shock hazard.
- Telling a missing control signal from a dead enable circuit requires a meter and the machine's own diagnostics.
- Replacing the wrong board costs time and does not remove the cause.
How error code Eio 38 differs from similar codes
Eio 38 is an enable that cannot be turned on. Eio 39 is an enable that cannot be turned off, and Eio 29 and 33 are the pin and circuit hardware checks.
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
Is Eio 38 the same as Eio 39?
No. Eio 38 means the enable will not turn on; Eio 39 means it will not turn off.
Does Eio 38 mean the machine is damaged?
It means the board's outputs cannot be enabled. Water, load and balance are not involved.
Will powering off clear it?
Only until the next start-up, when the enable check fails again.
Need help with Speed Queen error code Eio 38?
A technician confirms the cause on site and gives you the price in writing before any work starts.