UniMac Washer-Extractor Error Code E d Co: Drive Board Link Lost
E d Co is a drive board communication error on a UniMac QN washer-extractor. The front-end control cannot reach the board that drives the motor. Cycle the power once, and call us if it returns.
High: the drum cannot be started or stopped while the link is down, so the machine is out of service.
- Code
- E d Co
- Maker
- UniMac
- Equipment
- Industrial laundry
- Applies to
- CHM1792C family washer-extractor (QN models, 20-100 lb) front-end control
What does UniMac error code E d Co mean?
E d Co on a UniMac QN washer-extractor such as the UCA020QN is a drive board communication error. Two boards share the work of turning the drum. The front-end control decides what the drum should do, and the drive board carries it out. They talk over a cable. When the control no longer receives answers from the drive board, it cannot start or stop the drum. The display holds the code while the machine stands still.
The cause sits in the link or at its far end. A damaged or pinched cable between the control and drive board is one. A connector loose at either end is another. A drive board that is not powered or has failed will not answer. A missing power feed to the drive board looks exactly the same from the front panel. Unlike the setup code E d 01, here the boards are not exchanging anything at all.
Disconnecting and reconnecting power, the maker's operator step, may bring the link back.
Affected models and control systems
E d Co is listed for the CHM1792C family washer-extractors, the QN models from 20 to 100 lb, with the front-end control and drive board; the manual's example model is the UCA020QN.
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 display shows E d Co and the washer stands still
- Keys respond but the drum never moves
- The drive board has no activity light
- The code returns right at power-up
Possible causes
Listed in UniMac's documentation
- A damaged or pinched cable between the control and drive board
- A connector loose at either end of the drive link
- A drive board that is not powered or has failed
- A missing power feed to the drive board
Other likely causes — what usually sits behind error code E d Co on this control. A technician confirms which one it is before any part is replaced.
- Cable crushed under a panel after earlier service
- Fuse or supply lead feeding the drive board open
- Corrosion on the link connector pins
- Drive board processor locked up after a power surge
Safe checks before calling for service
- Disconnect and reconnect power to the machine, as the maker's operator step says.
- Wait for the display to settle.
- Do not open the cabinet.
- If E d Co returns, call us, and tell us what other messages the display shows.
How a technician diagnoses error code E d Co
- Read the code and check whether the drive board shows signs of power.
- Lock out the machine and measure the supply to the drive board.
- Inspect the link cable and both connectors.
- Reseat connectors and test the cable for continuity.
- Replace the cable or the drive board according to the result.
- Checking the supply to the drive board means measuring live 208 to 240 V circuits.
- A pinched cable inside the cabinet is found by tracing it, not by guessing.
- A dead drive board and a missing power feed look the same until measured.
How error code E d Co differs from similar codes
E d Co is the loss of the link to the drive board, while E Co is the loss of the SCI link to the input and output board.
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
Why does the keypad still respond?
The keypad is part of the front-end control. Only the link to the drive board is missing.
Will power cycling fix it?
It may bring the link back if the cause was a brief upset. If not, the code returns.
Is E d Co the same as E Co?
No. E d Co names the drive board link, E Co the SCI link to the input and output board.
Need help with UniMac error code E d Co?
A technician confirms the cause on site and gives you the price in writing before any work starts.