How long does a repair take?

Most repairs are completed within 1 to 5 business days, depending on the fault, parts availability, and repair complexity. Customers are informed if additional time is required.

What is not covered under the warranty?

The warranty does not cover physical abuse, accidental damage, liquid exposure, power surges, lightning strikes, tampering, or faults unrelated to the original repair.

Do you offer collection and delivery services?

Collection and delivery options may be available depending on location. Customers can contact CCRS Electronics directly to discuss available arrangements and costs.

How will I know when my repair is complete?

CCRS Electronics contacts customers by phone, WhatsApp, or SMS once the device has been repaired, tested, and is ready for collection.

Why should I choose CCRS Electronics?

CCRS Electronics offers professional diagnostics, board-level repair expertise, quality workmanship, transparent communication, and warranty-backed repairs.

Are your repairs tested before collection?

Yes. Every repaired device undergoes testing and quality checks before it is returned to the customer.

Xbox

Xbox Series X Black Screen & NB7N Retimer IC Hardware Repair Guide

Does your Xbox Series X or Series S power on with a solid white light, but your TV displays "No Signal" or gets stuck in low-resolution 640x480 mode? Learn how the NB7N621M HDMI 2.1 retimer chip is diagnosed and replaced.

Key Diagnostic Takeaways

The Xbox Series X relies on an OnSemi NB7N621M HDMI 2.1 retimer chip to clean and amplify high-speed 4K/120Hz TMDS and FRL data packets.
Lightning storms, load-shedding surges, and bent HDMI port ground pins frequently blow the retimer chip or ESD protection diode arrays.
Low-resolution mode (640x480) happens when the DDC lines handshake but high-speed differential pairs are dead.
CCRS Electronics replaces damaged HDMI 2.1 ports and performs micro-soldering BGA rework on the NB7N621M retimer chip.

Technical Repair Matrix & Specifications

Retimer IC Part	OnSemi NB7N621M 3.3V Ultra-Low Jitter Redriver
HDMI Interface	HDMI 2.1 FRL 48Gbps 4K/120Hz & 8K/60Hz
ESD Array Protection	Semtech ESD Protection Diode Arrays
Power Rails	3.3V Standby and 1.8V VDD Retimer Rails
Turnaround Time	24 to 48 Hours
Laboratory Warranty	3 to 6 Months Warranty

Laboratory Step-by-Step Micro-Soldering Protocol

Step 1: HDMI Port Physical Pin Microscope Inspection

🛠️ Trinocular Microscope 45x

Inspect all 19 HDMI pins under 45x magnification to verify if internal tongue is broken or pins are bridging.

Step 2: Diode Mode Line Probing & ESD Array Check

🛠️ Digital Multimeter with Micro-Needle Probes

Measure diode mode drop on all 4 TMDS/FRL differential pairs. A reading below 0.350V or short to ground points to a fried NB7N chip.

Step 3: BGA Hot-Air Desoldering of Faulty NB7N IC

🛠️ Hot Air Rework Station & Kapton Tape

Apply thermal shield tape over adjacent filter caps and remove the defective NB7N621M QFN IC at 360°C.

Step 4: New Retimer IC Alignment & 4K/120Hz HDR HDMI Testing

🛠️ 4K/120Hz OLED Test Display & High-Speed HDMI 2.1 Cable

Align and solder a brand-new genuine OnSemi NB7N621M chip and stress-test output at full 4K 120Hz HDR VRR.

Frequently Asked Questions

Q: Why does my Xbox work in low-resolution 640x480 mode but go black when I select 4K or 1080p?

A: The low-resolution boot uses basic DDC handshake lines. Once the console switches to high-speed FRL/TMDS bandwidth, the fried NB7N retimer fails to send the video signal.

Q: Can power surges or load shedding blow the Xbox HDMI retimer chip?

A: Yes. Voltage differentials between your TV HDMI board and the Xbox ground rail during power restoration send high-voltage spikes directly into the retimer IC.

Q: How long does an Xbox Series X HDMI retimer repair take?

A: Typically 24 to 48 working hours in our laboratory.

Need This Repaired Professionally?

Our Pretoria laboratory provides certified 1–5 days turnaround, nationwide courier collection, and a 3-6 month warranty.

View Xbox Series X|S Repair Services Book Repair Diagnostic WhatsApp Us (+27 68 235 8839)