🔬 Our Component-Level Repair & Testing Workflow
How every faulty PCB is diagnosed, restored, and calibrated inside our laboratory:
Checking switching DC voltages (3.3V, 5V, 12V, 15V) to protect main MCU processor.
Desoldering burnt power transistors; installing OEM modules with high-temp heat paste.
Oscilloscope testing of serial communication wave, replacing degraded optocouplers.
Run under real compressor & fan motor load on our test rig before return courier.
⚡ Common Faults & Symptoms Restored by Our Engineers:
We repair the following component failures with a 90-day warranty:
Indoor-Outdoor Serial Communication Bus Diagnosis & Component Repair
Communication faults like Daikin U4, Voltas E6, LG CH05, and Samsung E464 represent over 40% of inverter AC breakdowns in India. We isolate and replace failed high-speed optical isolators, voltage divider networks, and transient voltage suppressor (TVS) diodes to re-establish synchronous handshake signals.
🏢 Supported Inverter AC & Appliance Brands:
We stock original OEM power modules, IGBTs, bridge rectifiers, and microcontrollers for all brands:
❓ Frequently Asked Questions
Common questions regarding diagnostic bench testing, pricing, and courier handling:
Why does my AC show U4 / E6 / CH05 communication error?
This occurs when high voltage surges or neutral disconnects burn the optocouplers or communication resistors linking indoor and outdoor boards.
Do I need to send both indoor and outdoor PCBs for repair?
Sending both boards allows our lab to interconnect them on our bench and guarantee complete communication handshake before return.
How fast can a communication fault board be repaired?
Our express bench typically completes communication circuit diagnostics within 24 hours.
Do you provide a warranty on repaired inverter boards?
Yes! Every repaired board includes our 90-day replacement and repair warranty for complete peace of mind.
📍 All-India City Pages for Inverter AC Communication Error (U4, E6, CH05, E464) Micro-soldering
Click on your city to inspect local courier pickup schedules and turnaround time: