What It Means
Compressor C1 current sensor output stuck high.
Carrier Packaged Unit
Carrier Packaged Unit Error Code 104
Troubleshooting guide for the Carrier Packaged Unit system fault 104.
Possible Causes
- Wiring error or shorted current sensor cable.
- Sensor improperly clamped onto compressor wire.
- Faulty current sensor element.
Not sure which one it is — or if it's none of these? Try ACLogics today.
Disclaimer: This information is for general reference. Error codes can vary by model and production year. Always refer to your machine's specific manual and the information printed on the unit itself.
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Full Diagnosis
Current Sensor Failure - Compressor C1. Current sensor output is stuck high, usually due to wiring error or loose connection.
All Recorded Causes
Check compressor C1 current sensor wiring, connector, and mounting. Verify current sensor is correctly clamped on compressor wire. Measure sensor output. Replace current sensor if output is stuck high.
Verify Before Replacing Parts
- Confirm the exact Carrier model family and outdoor packaged units context before acting on a generic code description.
- Verify the sensor or thermistor reading against the expected range for the current operating condition, keeping in mind that check compressor C1 current sensor wiring, connector, and mounting.
- Check the sensor harness and board connection before condemning the sensor itself; on Carrier units this is also where you'd confirm verify current sensor is correctly clamped on compressor wire.
- After the correction, run the system long enough to confirm the outdoor packaged units fault does not return under normal load.
Still unsure about this fault?
ACLogics walks you through Carrier Packaged Unit diagnostics step-by-step — so you confirm the cause before swapping parts.
