Maytag Washer H98 Error Code: Causes and Fixes

The H98 error on your Maytag microwave means the control board has detected a problem with the humidity sensor circuit or the relay that powers it. This usually stops the microwave from running Sensor Cook or Sensor Reheat cycles until the fault is cleared or the part is replaced.

What the H98 error means

Maytag microwaves use a humidity sensor to detect steam released from food, which tells the control board when a dish is done cooking during Sensor Cook cycles. The H98 code appears when the board loses communication with this sensor or detects that the relay controlling it isn’t switching correctly. It’s the microwave’s way of protecting itself and letting you know a component needs attention rather than continuing to guess at cook times.

Common causes

• Humidity sensor has failed or become disconnected from the control board
• Corroded, loose, or damaged wiring harness connector at the sensor or relay
• Relay on the control board has failed or is sticking open/closed
• Moisture or grease buildup around the sensor vent affecting readings
• Control board fault unrelated to the sensor itself, but flagged through the same circuit
• Power surge or electrical spike that disrupted the board’s memory

How to fix the H98 error

1. Power cycle the microwave. Unplug it for 60 seconds, or switch off the breaker if it’s hardwired, then restore power. This clears many temporary board errors, including false H98 readings.
2. Check for physical blockage. Open the microwave and inspect the vent area near the humidity sensor for grease, food residue, or steam damage. Clean gently with a damp cloth and let it dry fully before testing again.
3. Inspect the wiring harness. With the unit unplugged, remove the outer cabinet (or access panel per your model) and check the connector running from the humidity sensor to the control board. Look for corrosion, loose pins, or chafed wires.
4. Test the sensor with a multimeter. Compare resistance readings against the values in your model’s tech sheet. A sensor reading open, shorted, or wildly out of range needs replacing.
5. Inspect the relay on the control board. If the sensor tests fine but the fault persists, the relay itself may be faulty. This usually means replacing the control board, since relays are typically soldered on rather than swapped individually.
6. Call a qualified appliance technician if you’re not comfortable testing electrical components or if the control board needs replacing — this repair involves mains voltage and should be handled safely.

While H98 is specific to microwaves, plenty of other Maytag appliances throw their own diagnostic codes. If you’re also troubleshooting a washer, guides like Maytag Washer F1 Error Code: Causes and Fixes, Maytag Washer F2 Error Code: Causes and Fixes, and Maytag Washer F3 Error Code: Causes and Fixes cover similar sensor and relay-related faults. For persistent issues after a power cycle, the Maytag Washer F5 Error Code: Causes and Fixes guide also explains how control boards handle repeated fault detection. If you work with other electronics that use temperature or humidity-style sensors, the troubleshooting steps in Panasonic Projector ERROR Error Code: Causes and Fixes follow a similar diagnostic logic.

FAQ

Can I still use my microwave with an H98 error showing?
Sometimes yes — manual or timed cooking modes may still work since they don’t rely on the humidity sensor. Sensor Cook and Sensor Reheat settings will likely be disabled until the fault is fixed.

Is the humidity sensor expensive to replace?
The part itself is usually inexpensive, but labor costs can add up if you’re hiring a technician. Many homeowners with basic electrical skills can replace it themselves after unplugging the unit and following the model-specific service guide.

Will unplugging the microwave permanently fix H98?
Not always. A power cycle clears temporary glitches, but if the sensor or relay has actually failed, the error will return once you try to use a sensor-based cooking cycle again.