If you are shopping for a diagnostic tool, you will have come across two acronyms that never used to appear: CAN-FD and DoIP. They are the ways the newest cars let their control units talk to the outside world. CAN-FD is an evolution of the CAN bus that carries more data in each message, and faster; DoIP is diagnostics over Ethernet through the car's own OBD2 socket. If your scanner doesn't understand them, it will fall short on some modern cars.
What CAN-FD is
The CAN bus is the network the car's control units have used to talk to each other for decades, and the protocol OBD2 diagnostics runs on in most vehicles. Its limit is message size: each frame carries no more than 8 bytes of data.
CAN-FD (Flexible Data-rate) stretches each frame to 64 bytes and lets the data part of the message travel faster. More information in less time, which is exactly what cars packed with driver aids, cameras and sensors need. Some manufacturers already use it on their latest platforms, and a diagnostic tool that only speaks classic CAN may fail to communicate with those control units.
What DoIP is
DoIP (Diagnostics over Internet Protocol, standard ISO 13400) runs diagnostics over Ethernet instead of CAN. It uses OBD2 socket pins that CAN leaves free, so the socket is the same as always. The big advantage is speed: Ethernet moves far more data, and you notice it above all when programming and coding control units, where large files are transferred.
BMW was one of the first to use it: its F-series models connect through a dedicated Ethernet lead known as the F-Chassis cable. Other manufacturers have been adding it to their recent cars, mainly for programming.
Why it matters when you buy
For everyday servicing on most cars on the road today, classic CAN is still enough. But you buy a diagnostic tool to last several years. If you work on recent cars, or want to code control units on makes that already use Ethernet, you want your tool to speak CAN-FD and, ideally, DoIP.
A tool supporting a protocol does not mean it can perform every function on every car that uses it. What you can do depends on the make, model, year and control unit. If in doubt, send us the VIN.
Which iCarsoft tools support CAN-FD and DoIP
| Model | CAN-FD | DoIP | Price |
|---|---|---|---|
| CR Pro | Yes | Not listed in its spec sheet | €279.95 |
| CR Pro+ | Yes | Not listed in its spec sheet | €339.95 |
| V2.0 single-brand (VAWS, BMM, MB…) | Yes | Not listed in its spec sheet | €194.95 |
| CR Max | Yes | Optional, with an accessory sold separately | €499.99 |
| CR Max BT | Yes | Optional, with an accessory sold separately | €559.95 |
| CR Max P | Yes | Built in, cables included | €649.95 |
| CR Ultra | Yes | Yes | €1,489.95 |
| CR Ultra P | Yes | Yes, plus J2534 | €1,749.95 |
| HD V4.0 (trucks) | Yes | Not listed in its spec sheet | €449.95 |
Built-in or optional DoIP
There are two ways to get it in the CR Max range. The CR Max P has it as standard: the box includes the RJ45 network cable, the F-Chassis cable for BMW and a USB-to-Ethernet adapter. On the CR Max and CR Max BT, DoIP is optional and you need to buy the accessory separately. If you know you will use it, the Max P works out better value; we go into detail in CR Max vs CR Max P.
The CR Ultra and CR Ultra P support CAN-FD and DoIP and come with the BMW F-Chassis cable, an RJ45 cable and a USB-to-Ethernet adapter in the case. The Ultra P adds J2534 pass-thru for working with the manufacturer's official software, as we explain in CR Ultra vs CR Ultra P.
How to tell if your car needs them
There is no rule by year that holds for every make, because each manufacturer has adopted them at its own pace and not always across all models at once. A few clues:
- If a diagnostic tool that reads other cars fine cannot talk to some control units on a recent model, the protocol may be the problem.
- If the manufacturer requires a dedicated Ethernet cable for dealer programming, such as BMW's F-Chassis cable, the car uses DoIP.
- Cheap ELM327-style OBD2 readers stick to the classic OBD2 protocols and are no use on these networks.
Heavy vehicles are going the same way. The HD V4.0 truck tool supports CAN-FD as well as industry protocols such as SAE J1939 and J1708, so it keeps up with the latest trucks.
The safe way to find out is to check against the VIN. Send it to us and we will tell you which tool in the range suits your car.
What we recommend
- Driver with a car a few years old: CAN-FD is plenty. The CR Pro, the CR Pro+ and the V2.0 single-brand tools already support it.
- Driver with a recent car, or a coding enthusiast: the CR Max P, which brings together CAN-FD, built-in DoIP and OE coding across 8 brand groups.
- Garage: DoIP as standard at the very least. The CR Max P to start, and the CR Ultra or CR Ultra P if you do programming. More detail in which diagnostic tool to buy for a garage.
You can compare every model under multi-brand diagnostic tools and, if you are a professional, under workshop diagnostic tools.
