Error code reference

Carrier Furnace Error Code 43

Low-heat pressure, draft safeguard (when used), or auxiliary limit switch (when used) open while high-heat pressure switch is closed.

SourceCarrier 58T - Service Manual: 2-Speed Gas Furnaces (58TMA, 58TUA)Fig. 13 Service Label

Carrier codes Carrier furnace codes

Diagnostic procedure

The full 43 procedure

Step 1 is visible so you can confirm you are on the right page. The remaining steps, the ones that tell you whether to actually replace a part, unlock with any pass.

MyPros+ · DiagnosticsStep 1 preview

First diagnostic step

Check for pressure switch stuck open, disconnected or obstructed pressure tubing; refer to codes 32 and 33.

SourceCarrier 58T - Service Manual: 2-Speed Gas Furnaces (58TMA, 58TUA)Fig. 13 Service Label

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More steps, wiring diagram references, and verified part numbers

Includes expected resistance and voltage values, connector pinouts, and supersession notes for replacement parts.

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Where this code is documented

1 manual in the MyPros+ library documents this code for Carrier furnace.

Models covered by the manuals that document this code

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The full 43 procedure

Where this code is documented

Models covered by the manuals that document this code

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