Split AC EH03 / EC07 Error Code Fix – Step-by-Step Troubleshooting Guide

Split AC EH03 / EC07 Error Code Fix – Step-by-Step Troubleshooting Guide

Error Description

EH03 ya EC07 Error Code ka matlab hai ki Indoor ya Outdoor DC Fan Motor ki speed normal range se bahar hai. PCB ko fan motor se proper speed feedback (FG Signal) nahi milta, isliye system protection mode mein chala jata hai aur compressor band kar deta hai. Kai inverter platforms mein EH03 indoor fan speed abnormal aur EC07 outdoor fan speed abnormal ko indicate karta hai.

Step 1 – Power Reset

Sabse pehle AC ko Main Power Supply se OFF karein.

  • 2–5 minute wait karein.
  • Dobara power ON karke AC start karein.

Agar error phir bhi aaye to next step follow karein.

Step 2 – Fan Blade Check

Indoor ya Outdoor fan blade ko haath se ghuma kar check karein.

Check

  • Blade freely rotate ho raha hai?
  • Koi obstruction to nahi?
  • Dust ya foreign object to nahi fasa?

Solution

  • Obstruction remove karein.
  • Blade clean karein.
  • Damaged fan blade replace karein.

Step 3 – Fan Motor Wiring Check

Fan Motor connector aur PCB connector inspect karein.

Check

  • Loose Connector
  • Burnt Terminal
  • Broken Wire
  • Water Damage

Solution

  • Wiring repair karein.
  • Loose connector ko properly fit karein.
  • Burnt connector replace karein.

Step 4 – Measure Fan Motor Supply Voltage

Outdoor DC BLDC Fan Motor par voltage measure karein.

Typical Voltage (230V Models)

  • Pin-1 (Vs/Vm) → 280–340 VDC
  • Pin-3 (GND) → 0 V
  • Pin-4 (Vcc) → 14–17 VDC
  • Pin-5 (Speed Command) → 0–5.6 VDC
  • Pin-6 (FG Feedback) → 14–17 VDC (model dependent)

Solution

Agar required voltage nahi mil rahi hai to Outdoor PCB fault ho sakta hai.

Step 5 – BLDC Fan Motor Resistance Test

UVW connector disconnect karein.

Resistance measure karein.

  • U–V
  • V–W
  • W–U

Normal Condition

Teeno resistance lagbhag equal honi chahiye.

Solution

Agar resistance unequal ho to Fan Motor defective hai.

Fan Motor replace karein.

Step 6 – Check Fan Rotation

Power ON karke observe karein.

Symptoms

  • Fan bilkul start nahi hota.
  • Fan jerk karta hai.
  • Fan slow rotate karta hai.
  • Fan start hokar turant stop ho jata hai.

Possible Cause

  • BLDC Fan Motor Fault
  • Fan Driver Circuit Fault
  • Outdoor PCB Fault

Step 7 – Check Indoor Fan Motor (EH03)

Agar EH03 error hai to Indoor Fan Motor check karein.

Check

  • Fan freely rotate karta hai?
  • Indoor Fan Motor supply voltage
  • FG Feedback Signal
  • Indoor PCB

Solution

Faulty Fan Motor ya Indoor PCB replace karein.

Step 8 – Check Outdoor Fan Motor (EC07)

Agar EC07 error hai to Outdoor Fan Motor inspect karein.

Check

  • Fan Motor
  • UVW Cable
  • Connector
  • Outdoor PCB
  • Fan Driver Circuit

Solution

Faulty Fan Motor ya Outdoor PCB replace karein.

Step 9 – Check Outdoor PCB

Agar Fan Motor aur Wiring dono normal hain.

Check

  • Fan Driver IC
  • MOSFET/IPM Driver
  • Power Supply Circuit
  • PCB Burn Marks

Solution

Outdoor PCB repair ya replace karein.

Step 10 – Final Verification

Repair complete hone ke baad

  • Cooling Mode start karein.
  • Fan Speed observe karein.
  • Compressor running check karein.
  • Error Code clear hua ya nahi verify karein.
  • Minimum 15–20 minutes trial run karein.

Recommended Troubleshooting Sequence

  1. Reset Power Supply
  2. Check Fan Blade Rotation
  3. Inspect Fan Wiring & Connectors
  4. Measure Fan Supply Voltage
  5. Measure UVW Resistance
  6. Check FG Feedback Signal
  7. Test Indoor/Outdoor Fan Motor
  8. Inspect Outdoor PCB
  9. Replace Faulty Component
  10. Perform Final Trial Run

Safety Precautions

  • Main Power OFF karke hi servicing karein.
  • DC Bus Capacitor discharge hone ka wait karein.
  • Insulated tools aur PPE ka use karein.
  • Rotating fan blades ke paas kaam karte waqt extra caution rakhein.
  • Voltage measurement sirf trained technician hi kare.

Common Symptoms

Symptom Possible Cause
EH03 Error Indoor Fan Speed Out of Control
EC07 Error Outdoor Fan Speed Out of Control
Fan Not Rotating Fan Motor Fault
Fan Rotates Slowly Bearing ya Motor Fault
Fan Jerks Only Driver Circuit Fault
Compressor Stops After Few Seconds Fan Feedback Missing
Fan Voltage Missing PCB Fault
UVW Resistance Unequal BLDC Fan Motor Fault

💡 Service Technician Tip

Outdoor PCB ya Indoor PCB replace karne se pehle hamesha Fan Blade, BLDC Fan Motor, UVW Resistance, Fan Wiring, Connectors aur Supply Voltage verify karein. Kai cases mein sirf loose connector, blocked fan blade ya defective fan motor ki wajah se EH03 ya EC07 error aata hai. Root cause identify kiye bina PCB replace karne se unnecessary repair cost badh sakti hai.

Error Description

The EH03 or EC07 error code indicates that the Indoor or Outdoor DC BLDC Fan Motor speed is abnormal. The control PCB is unable to receive the correct fan speed feedback (FG Signal), so it stops the compressor to protect the air conditioner.

Typically:

  • EH03 – Indoor Fan Motor Speed Abnormal
  • EC07 – Outdoor Fan Motor Speed Abnormal

Step 1 – Reset the Air Conditioner

Switch OFF the main power supply.

  • Wait for 2–5 minutes.
  • Turn the power back ON and restart the AC.

If the error reappears, continue with the following steps.

Step 2 – Check the Fan Blade

Manually rotate the indoor or outdoor fan blade.

Check

  • Does the fan blade rotate freely?
  • Is there any obstruction?
  • Is dust or a foreign object blocking the fan?

Solution

  • Remove any obstruction.
  • Clean the fan blade.
  • Replace the fan blade if damaged.

Step 3 – Inspect Fan Motor Wiring

Check the fan motor wiring and connectors.

Inspect

  • Loose connectors
  • Burnt terminals
  • Broken wires
  • Water damage

Solution

  • Repair damaged wiring.
  • Secure loose connectors.
  • Replace burnt connectors.

Step 4 – Measure Fan Motor Supply Voltage

Measure the supply voltage at the DC BLDC fan motor.

Typical Voltage (230V Models)

  • Pin-1 (Vs/Vm): 280–340 VDC
  • Pin-3 (GND): 0 VDC
  • Pin-4 (VCC): 14–17 VDC
  • Pin-5 (Speed Command): 0–5.6 VDC
  • Pin-6 (FG Feedback): 14–17 VDC (Model Dependent)

Solution

If the required voltages are missing, the outdoor PCB may be defective.

Step 5 – Test BLDC Fan Motor Resistance

Disconnect the UVW connector from the fan motor.

Measure the resistance between:

  • U–V
  • V–W
  • W–U

Normal Condition

All three resistance values should be nearly equal.

Solution

If the resistance values are unequal, replace the BLDC fan motor.

Step 6 – Observe Fan Operation

Turn the power ON and observe the fan.

Symptoms

  • Fan does not rotate
  • Fan jerks only
  • Fan rotates slowly
  • Fan starts and stops immediately

Possible Causes

  • Faulty BLDC fan motor
  • Fan driver circuit failure
  • Outdoor PCB fault

Step 7 – Check Indoor Fan Motor (EH03)

If the error code is EH03, inspect the indoor fan motor.

Check

  • Fan blade rotation
  • Fan motor supply voltage
  • FG feedback signal
  • Indoor PCB

Solution

Replace the faulty indoor fan motor or indoor PCB if required.

Step 8 – Check Outdoor Fan Motor (EC07)

If the error code is EC07, inspect the outdoor fan motor.

Check

  • Outdoor fan motor
  • UVW cable
  • Wiring connectors
  • Outdoor PCB
  • Fan driver circuit

Solution

Replace the faulty outdoor fan motor or outdoor PCB if necessary.

Step 9 – Inspect the Outdoor PCB

If the fan motor and wiring are normal, inspect the outdoor PCB.

Check

  • Fan driver IC
  • MOSFET/IPM driver
  • Power supply circuit
  • Burnt PCB components

Solution

Repair or replace the outdoor PCB.

Step 10 – Final Verification

After completing the repair:

  • Start the AC in Cooling Mode.
  • Verify fan operation.
  • Check compressor operation.
  • Confirm the error code has cleared.
  • Perform a 15–20 minute trial run.

Recommended Troubleshooting Sequence

  1. Reset the power supply.
  2. Check fan blade rotation.
  3. Inspect wiring and connectors.
  4. Measure fan motor supply voltage.
  5. Measure UVW winding resistance.
  6. Check FG feedback signal.
  7. Test the indoor or outdoor fan motor.
  8. Inspect the outdoor PCB.
  9. Replace the faulty component.
  10. Perform a final operational test.

Safety Precautions

  • Turn OFF the main power supply before servicing.
  • Allow the DC bus capacitor to discharge before handling the PCB.
  • Wear appropriate PPE and use insulated tools.
  • Keep hands clear of rotating fan blades during testing.
  • Live voltage measurements should only be performed by trained technicians.

Common Symptoms

Symptom Possible Cause
EH03 Error Indoor fan speed abnormal
EC07 Error Outdoor fan speed abnormal
Fan not rotating Faulty fan motor
Fan rotates slowly Bearing or motor failure
Fan jerks only Driver circuit fault
Compressor stops after a few seconds Missing FG feedback signal
No fan supply voltage Outdoor PCB fault
Unequal UVW resistance BLDC fan motor winding fault

Service Technician Tip

Before replacing the indoor or outdoor PCB, always inspect the fan blade, BLDC fan motor, UVW winding resistance, wiring, connectors, and supply voltage. In many cases, the root cause is a loose connector, blocked fan blade, or defective fan motor. Identifying the actual fault before replacing the PCB helps avoid unnecessary repair costs and prevents repeat failures.

Back to blog