UniMac Commercial Washer Error Code E d 63: IPM Sensor Shorted
E d 63 on a UniMac QN washer-extractor is a fatal IPM temperature short error from the drive hardware. The sensor that reads the drive's power module temperature reads shorted. Turn off the power to reset the drive, keep the area dry and do not open the cabinet.
High: without a working temperature reading the drive will not run, and a fatal code stops the machine.
What does UniMac error code E d 63 mean?
The power module in the drive has a built-in temperature sensor, so the drive can tell how hot the module is getting. If that sensor circuit reads shorted, the drive no longer has a usable temperature, and it cannot tell whether the module is cool or about to burn. For safety it stops. E d 63 is that stop, and it is a fatal one. This is a drive board hardware failure and not an overheat of the motor, which would show as E d 22. A shorted sensor circuit on the board is the main cause. A loose connector at the sensor input, or moisture or damage on the board near the sensor, can create the same reading. Turning off the power resets the drive, but a real short stays until the board is repaired. Its open-circuit partner is E d 64.
Affected models and control systems
This applies to UniMac QN washer-extractors of 20 to 100 lb, such as the UCA020QN, in the CHM1792C family with the front-end control and drive 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
- E d 63 on the display
- Washer refusing to start after a reset
- No spin and no motor sound
Possible causes
Listed in UniMac's documentation
- A shorted module temperature sensor circuit on the drive board
- A loose connector at the drive board sensor input
- Moisture or damage on the drive board near the sensor
Other likely causes — what usually sits behind error code E d 63 on this control. A technician confirms which one it is before any part is replaced.
- Condensation on the board after the cabinet cooled quickly in a humid room
- A conductive film of lint and detergent dust near the sensor pads
- A board corner cracked by an impact during a past service
Safe checks before calling for service
- Turn off the power at the machine to reset the drive.
- Do not open the cabinet.
- Check that the area around the machine is dry.
- Another E d 63 means you should call us.
- Write down the time the code appeared.
How a technician diagnoses error code E d 63
- Confirm the code reappears after a power cycle and the drive is not physically hot.
- With power locked out and the drive discharged, inspect the board near the sensor for moisture, dust or cracks.
- Check the sensor connector for seating and corrosion.
- Measure the sensor circuit for a short and compare it with the expected value.
- Check the board part number for the machine.
- Replace the drive board when the sensor circuit fails the test.
- The drive board holds stored charge and sits near live 208 to 240 V terminals.
- Distinguishing a shorted sensor from a real overheat takes a measurement, not an assumption.
- A moisture problem on the board needs the source found, or the new board suffers the same.
How error code E d 63 differs from similar codes
E d 63 is the shorted sensor reading, E d 64 is the open one, and E d 25 is a genuine over temperature.
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 washer error codes
Is the drive actually hot?
Usually not. The code says the temperature sensor circuit reads shorted.
Is it the same as E d 25?
No. E d 25 means the module really got too hot. E d 63 is a sensor circuit failure.
Could water cause it?
Yes. Moisture near the sensor can short the circuit, so we check the area as well as the board.
Need help with UniMac error code E d 63?
A technician confirms the cause on site and gives you the price in writing before any work starts.