System Diagnosis
5V PCM Power Out of Range Lockout. PCM 5V DC supplied to VFD is interrupted or out of range, shutting the system down if not restored.
Carrier Heat Pumps
Error Code 24-58
Troubleshooting guide for the Carrier Heat Pumps system fault 24-58.
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.
Potential Causes & Solutions
- Check PCM power supply for proper 5V DC output.
- Inspect wiring between PCM and VFD for damage.
- Measure 5V DC bus voltage with a meter.
- Replace PCM if internal power supply is faulty.
Verify Before Replacing Parts
- Confirm the exact Carrier model family and heat pumps context before acting on a generic code description.
- Start with line voltage, low voltage, and board output checks in sequence so the fault is isolated cleanly.
- Inspect connectors, relay outputs, and any recently replaced electrical parts for mismatch or loose fit.
- After the correction, run the system long enough to confirm the code does not return under normal load.
Field Signals to Confirm
What usually confirms it
Missing voltage, inconsistent outputs, or a fault that changes when a connector is reseated.
What can fool you
Intermittent power quality and field wiring problems can mimic a failed board.
When to Escalate the Call
- You have unstable supply power, repeated fuse failures, or signs of board damage.
- The failure path involves multiple boards or field-modified wiring.
Still unsure about this fault?
ACLogics walks you through Carrier Heat Pumps diagnostics step-by-step — so you confirm the cause before swapping parts.
