01 · you
Vehicle
Parked, charging, ignition on.
How it works Remote diagnosis, step by step
A dealer-grade diagnostic bay, over the internet.
The engineer sits in China with the OEM's own diagnostic software. Your car sits in your driveway. Between them is a cable, a Windows PC and an encrypted link. This page explains each piece and what you need to have ready.
01 The connection chain
Vehicle to OEM cloud in six links.
02 · you
ENET cable
OBD-II to Ethernet. Any DoIP lead for most brands.
03 · you
Windows PC
Runs EV Fix Connector. No install skills needed.
04 · us
Encrypted link
A private tunnel over the internet. Diagnostic traffic only.
05 · us
OEM engineer's laptop
Factory diagnostic software, the same tool the dealer uses.
06 · us
OEM cloud
Security login, VIN-matched software, coding data.
What you provide
What we provide
Your side
The vehicle. Every modern Chinese EV exposes its controllers over diagnostic Ethernet (DoIP) through the OBD-II port under the dash. That is the port the factory and the dealer use for programming.
The ENET cable. A passive adapter, OBD-II plug on one end, RJ45 on the other. It simply routes the car's Ethernet pins to a normal network socket. No electronics, nothing to configure.
The Windows PC. Runs EV Fix Connector, our small connector app. It finds the car on the cable, opens an encrypted tunnel to us and shows you a live status. You never touch the OEM software yourself.
Our side
The encrypted link. A point-to-point tunnel that carries only the car's diagnostic packets. It does not share your screen, files or other devices on your network.
The engineer's laptop. Runs the manufacturer's own diagnostic and programming software with a licensed account. To that software, your car looks like it is plugged in on the bench.
The OEM cloud. Security authorisation, VIN-matched software packages and coding data come from the manufacturer's servers, the same source a dealer in China uses.
02 What you need
Two things, really. The rest is common sense.
An ENET cable and a Windows PC are the only purchases. Everything else on the list you almost certainly already have. If you are missing the cable, tick "I need one" on the booking form and we will add it to the quote.
- Windows 10 or 11 PC · laptop or desktop, with an Ethernet port or a USB Ethernet adapter
- ENET cable · OBD-II to RJ45, DoIP (ISO 13400). Generic works for most brands; we confirm on booking
- Internet · 10 Mbps or faster, wired or good Wi-Fi. A phone hotspot works for diagnosis but not for flashing
- Car on charge · traction battery above 50 % and on a charger, or a 12 V support unit for long flashes
- A phone · for the WhatsApp voice call with us during the session
- Time · a quiet 30 to 90 minutes where the car stays parked and no one opens the doors
03 A session, start to finish
From booking to report in six steps.
Engineers work Beijing time 09:00 to 21:00. Most customers in Europe, the Middle East and Asia-Pacific find a slot the same or next day.
You can watch the whole session and pull the cable at any moment. Nothing is written to the car without telling you first.
- You book
Fill in the form with the car, the symptom and any codes you already have. Photos of the dash help.
you · 5 minutes - We review and quote
We match your case with an engineer for the brand, check the software path for your VIN and send a fixed price with two or three time slots.
us · within 1 working day - You confirm and prepare
Pay the quote, install EV Fix Connector on the Windows PC and make sure the ENET cable reaches from the OBD port to the laptop. We send a one-page checklist.
you · before the slot - You connect
Car on a charger, ignition on, cable in, app open. Click connect and read us the session code. We confirm the engineer can see the car.
you + us · 5 minutes - The engineer works
Diagnosis, coding or flashing happens live. You stay on the call and can see progress in the app. For calibrations and actuator tests you may be asked to press a pedal or place a target.
engineer · 30 to 90 minutes - You get a report
A short written summary: what was found, what was changed, which software versions are now on the car, and anything to watch. Keep it for the next owner or insurer.
us · same day
04 Questions we get
Before you plug anything in.
What exactly is an ENET cable?
An OBD-II to RJ45 Ethernet adapter that exposes the car’s diagnostic Ethernet (DoIP, ISO 13400) to a laptop. Most Chinese EVs use it for programming. Any generic DoIP ENET cable works for most brands; a few brands need a brand-specific lead, which we will tell you when we review your booking. We can also ship you one.
Does the Windows PC need anything special?
Windows 10 or 11, a wired Ethernet port or a USB Ethernet adapter, and a stable internet connection of at least 10 Mbps. No admin knowledge required: our connector app walks you through it and we stay on a call with you.
Who actually works on my car?
Engineers who work for or with Chinese EV manufacturers and use the OEM diagnostic software every day. They sign in to the same OEM cloud the dealer uses. We coordinate the session and translate where needed.
How long does a session take and what does it cost?
Most sessions run 30 to 90 minutes. We quote a fixed price after reviewing your case, before anything is scheduled. If the engineer cannot do the job, you do not pay for the session.
Is it safe to let someone connect to my car remotely?
The link is an encrypted tunnel between your PC and the engineer’s workstation that only carries diagnostic traffic. The engineer sees the car’s diagnostic interface, not your PC screen or files. You can watch everything and unplug the cable at any time.
Can the update or coding brick my car?
The engineer uses the OEM procedure with the correct package for your VIN, which is the same process the factory uses. We ask you to keep the car on a charger and the 12 V battery supported during flashing, and we do not start a flash unless the connection is stable.
What about time zones?
Engineers are in China (UTC+8) and work 09:00 to 21:00 Beijing time, which covers Europe, the Middle East, Africa, Southeast Asia and Australia during their working day, and the Americas in the early morning or late evening.
My brand is not in the list. Can you still help?
Probably. The list shows brands we handle routinely. Send the booking form anyway with your model and we will tell you within a day whether we have an engineer for it.