Mitsubishi Air Conditioner Error PB

⚡ Quick Answer: The Mitsubishi Air Conditioner error code PB indicates a fault with the indoor fan motor. This may result from motor failure, wiring issues, or contro... ⚠️ Difficulty Varies

What Does Error PB Mean?

The Mitsubishi Air Conditioner error code PB indicates a fault with the indoor fan motor. This may result from motor failure, wiring issues, or control board malfunctions. Symptoms include the indoor fan not starting, intermittent fan operation, and the unit shutting down while displaying the PB code. It's essential to address this issue promptly to restore normal operation.

Common Symptoms:

  • Indoor fan does not start
  • Fan stops intermittently during operation
  • Unit may shut down and show PB code on display or remote controller

Possible Causes

  • Indoor fan motor winding failure or mechanical failure (high)
  • Fan motor connector or wiring issue (medium)
  • Indoor unit control board fault affecting fan motor control (medium)

How to Fix Error PB

DIY Fix Basic checks for PB error

  1. Turn off power and restart unit to confirm persistent PB code
  2. Check for any obvious obstructions preventing fan blade movement
  3. Ensure remote/controller displays code consistently and unit actually won’t run fan

Technician Only Technician-level diagnosis for PB error

  1. Disconnect power and inspect indoor fan motor windings for continuity and insulation resistance
  2. Check fan motor connector and wiring harness for corrosion, loose connection or damage
  3. Test or replace indoor fan motor if windings or bearings show failure
  4. Verify indoor unit control board outputs to fan motor and replace control board if needed

Parts needed: Indoor fan motor, Fan motor wiring harness/connectors, Indoor unit control board

🛑 When to Call a Pro:
  • If the PB code persists after basic checks
  • If fan motor windings or wiring cannot be safely tested by user
  • If internal control board faults are suspected

Next step

Choose the next step for PB

Confirm the diagnosis before ordering. An error code can identify the system involved, but it does not prove that a specific part has failed.

Based on diagnostic data

Most relevant component to inspect

Wiring Harness

Connects controls, sensors, motors, and other electrical components inside the appliance.

Typical part-only price
$20 - $120
DIY difficulty
Medium
Estimated time
30-90 mins
Where can I find the model number?

Check the rating label around the door, lid, frame, rear panel, or inside the appliance cabinet. Use the complete model number, including suffixes.

Find a part that fits my model

Verify the complete model and part number on the retailer's compatibility page before ordering.

Other parts options

Check related components first; use model search as a fallback.

Possible related component

HVAC Control Board

Controls fan, compressor, sensor, and communication functions in the HVAC unit.

$90 - $320 · Hard · 45-120 mins

Check fit & price
Model number required

Model-compatible Air Conditioner parts

Enter the complete model number to browse compatible replacement parts. This is a model-based parts search, not a diagnosis that a specific component failed.

Find a part that fits my model

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Optional routine care

Maintenance supplies

These products support cleaning or routine upkeep. They are separate from the possible repair components above and are not claimed to fix this error code or symptom.

Maintenance supply

Air Conditioner Fin Cleaner

For routine cleaning of accessible coil fins when permitted by the manufacturer. Disconnect power and follow product and appliance instructions.

View maintenance supply
Maintenance supply

Model-Compatible Washable AC Filter

A reusable filter option only where the appliance supports one. Match the full model, dimensions, and filter specification.

Compatibility check required: use the complete appliance model and compare the existing filter, bag, or specification before ordering.

Find one that fits my model

Affiliate disclosure: As an Amazon Associate I earn from qualifying purchases. Recommendations are based on routine-care relevance, not commission rate.

Technical Specifications

wattage 1200W
component Compressor
resistance 3-6 ohms
part_number Mitsubishi 5R00A00001
voltage_rating 230V AC

Common Questions

What does PB error mean on Mitsubishi Air Conditioner?

The PB error indicates a fault with the indoor fan motor, possibly due to motor failure, wiring issues, or control board malfunctions.

Can I fix Mitsubishi Air Conditioner PB error myself?

Yes, you can perform basic checks like restarting the unit and checking for obstructions. However, complex issues may require a technician.

How much does it cost to fix PB error?

Repair costs for the PB error typically range from $150 to $600+, depending on the parts needed and labor.

When should I call a technician for PB?

Call a technician if the PB code persists after basic checks, or if there are issues with the fan motor or control board that you cannot safely diagnose.

Sources & References

Data last verified: 2026-07-22

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