UniMac Washer-Extractor Error Code E d 64: Module Sensor Reads Open
E d 64 is a fatal IPM temperature open error on a UniMac QN washer-extractor. The sensor that reads the drive's power module temperature reads open, so the drive stops the cycle. Kill the power, keep the area clean and dry, and call us if it returns.
High: a fatal drive stop from a missing temperature signal that keeps the washer down.
- Code
- E d 64
- 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 64 mean?
E d 64 is a fatal IPM temperature open error from the drive hardware on a UniMac QN washer-extractor such as the UCA020QN. A sensor on the drive's power module reports its temperature, and the drive needs that reading to run safely. When the sensor circuit reads open, as if the wire had been cut, the drive loses its temperature signal and stops the cycle.
It is the open-circuit partner of E d 63 and points to the drive board. The motor and the water are not the problem. An open sensing circuit on the board is the principal cause. A connector near the module sensor may have pulled loose. Corrosion or a cracked trace near the sensor can break the circuit in the same way. A board with an open sensor circuit needs replacing.
Killing the power resets the message. An open circuit tends to come and go with vibration and temperature, so the code can disappear for a while and then return.
Affected models and control systems
E d 64 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 64 and the cycle stops
- The code may come and go with machine vibration
- It returns on every power-up once the circuit stays open
- The drive feels normal to the touch
Possible causes
Listed in UniMac's documentation
- An open temperature sensing circuit on the drive board
- A connector near the module sensor that has pulled loose
- Corrosion or a cracked trace on the drive board near the sensor
- A drive board with an open sensor circuit that needs replacing
Other likely causes — what usually sits behind error code E d 64 on this control. A technician confirms which one it is before any part is replaced.
- Solder joint at the sensor cracked by years of spin vibration
- Sensor wire stretched when the board was last moved
- Corroded contact from chemical vapor in the laundry room
- Thermistor inside the module has gone open
Safe checks before calling for service
- Kill the power to the washer so the message resets.
- Do not open the cabinet.
- Make sure the machine area is clean and dry.
- Call us if E d 64 comes back, and tell us the time it first came up.
How a technician diagnoses error code E d 64
- Read the code and confirm an open rather than a short reading.
- Lock out the machine and inspect the board near the sensor for corrosion and cracks.
- Reseat the sensor connector and check the lead.
- Measure the sensor circuit for continuity and expected resistance.
- Tap-test the board gently for an intermittent break before replacing it.
- Replace the drive board if the circuit stays open.
- A cracked trace or joint is found only by close inspection and measurement inside the cabinet.
- The drive board carries 208 to 240 V circuits and stored charge.
- Intermittent breaks need patient testing that is not safe for an operator.
How error code E d 64 differs from similar codes
E d 64 is the open-sensor reading, while E d 63 is the shorted-sensor reading of the same module temperature circuit.
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 code come and go?
An open circuit can reconnect for a moment when the machine vibrates or warms up.
Does E d 64 mean the module is hot?
No. It means the drive cannot read the module temperature at all.
Can I run the washer between occurrences?
We advise against it. The drive stops for safety whenever the sensor fails, and the problem will repeat.
Need help with UniMac error code E d 64?
A technician confirms the cause on site and gives you the price in writing before any work starts.