Wire pairs and resistance values from the ETOG-56 manufacturer instructions.
The ETOG-56 is an outdoor ground sensor that detects temperature and moisture and includes a heating element. A qualified technician should turn off the control supply and isolate the relevant sensor conductors before measuring resistance; do not use an ohmmeter on an energized circuit.
| Function | Wire pair | Manufacturer reference |
|---|---|---|
| Heating element | Brown–green | 220 Ω ±10% |
| Temperature | Grey–pink | 23 kΩ at 10°C; 38 kΩ at 0°C; 64 kΩ at −10°C |
| Moisture | Yellow–white | Dry: infinite/open; wet: below 200 kΩ; shorted: below 100 Ω |
Compare the temperature-sensor reading with its actual temperature. The moisture pair’s dry open-circuit reading is normal; do not treat that alone as a broken wire. A shorted moisture pair is a different condition from normal moisture detection.
Also inspect the exposed sensor surface. The instructions require it to remain uncovered, horizontal and within the heated area so it can collect representative snow or meltwater. Confirm the exact ETOG-56 wiring at the controller after testing; these colors and values are not universal for other sensors.
Source: attached OJ ETOG-56/ETOK-1 instructions, Figure 8 resistance table and installation instructions.
