Maytag Refrigerator PC1: Compressor Circuit Failure

PC1 means the compressor failed to start or run. The main control board detected that the compressor circuit did not draw the expected current after the start command was issued. The compressor start relay, overload protector, or the compressor motor itself is the suspect.

Compressor Start Sequence

When the board decides cooling is needed, it energizes the compressor circuit:

1. The start relay closes, connecting the start winding to the power supply (provides initial torque to overcome static friction)
2. The compressor motor begins rotating
3. Once the motor reaches operating speed (within 1-3 seconds), a PTC thermistor in the start relay heats up and opens the start winding circuit (motor runs on the run winding only)
4. The overload protector monitors current draw — if the motor draws excessive current (stalled, locked rotor), the overload trips and disconnects power to prevent motor damage

PC1 triggers when the board does not detect normal current draw within the expected startup window.

Diagnosis in Order

1. Start Relay Test (Most Common Failure — 40% of Cases)

The start relay is a small device plugged onto the compressor terminals at the rear-bottom of the refrigerator. On Maytag models with a PTC-type relay, it is a black or white plastic box approximately 2" x 2" x 1".

Test: Unplug the refrigerator. Pull the relay off the compressor terminals. Shake it gently — if you hear a rattling sound, the internal PTC disc has broken. Replace the relay.

Part: Start relay/overload combo device W10613606, $15-30. This is the most common and cheapest fix for PC1.

2. Overload Protector Test

The overload protector is sometimes integrated with the start relay or may be a separate disc-shaped device on the compressor. It should read near-zero resistance (continuity) when cool. If it reads open at room temperature, the overload has tripped and not reset — or has permanently failed.

Note: A tripped overload may reset after cooling for 30-60 minutes. If it resets, the compressor may start briefly before the overload trips again — indicating a compressor motor problem causing excessive current draw.

3. Compressor Winding Test

With the relay and overload removed, measure resistance across the three compressor terminals (Common, Start, Run):

• Common to Start: typically 3-8 ohms
• Common to Run: typically 3-6 ohms
• Start to Run: should equal the sum of C-S and C-R (within 1 ohm)
• Any terminal to compressor case (ground): should be infinite (no ground fault)

If any winding reads open or shorted, the compressor motor has failed. If a ground fault exists (any terminal reads any resistance to the case), the compressor must be replaced.

Compressor Replacement Economics

A Maytag refrigerator compressor replacement costs $400-800 including parts, labor, and refrigerant recharge (EPA-certified technician required for refrigerant handling). For a refrigerator over 8 years old, compressor replacement often exceeds 50% of a new unit's cost, making replacement of the entire refrigerator more economical.

PC1 After Power Outage

After a power outage, the compressor may try to restart against head pressure (residual high-side refrigerant pressure that has not equalized). The compressor stalls, the overload trips, and PC1 appears. Wait 10-15 minutes for pressures to equalize, then try again. Many refrigerators have a built-in 5-8 minute restart delay for exactly this reason.

Cost

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Maytag refrigerator not cooling with PC1? Start relay swap is a quick fix. Compressor diagnosis tells you if it is a $20 part or a replace-the-fridge situation. Book diagnosis.