Deutz-Fahr and John Deere emerged as the winners when it comes to Isobus. Both brands support a wide range of functions that also actually perform well, and they have integrated these seamlessly into the display or tractor.
Claas also achieved a very satisfactory score: a wide range of functionalities, works well, but it’s not (yet) capable of working with Isobus in its own tractor display. New Holland and Case IH also support many Isobus functions, but these are relatively poorly represented on the displays.
Major Isobus update by Agco
Valtra and Massey Ferguson lagged some way behind in the test. Agco has since completed a major update. Slowly but surely, all seven types of tractors will be fully functional.
You expect the Isobus to do three things. First, that the tractor sends a signal to the implement containing information such as travel speed and lifting height, for example. Second, it should have a universal display to which an implement will upload its own user interface. Finally, it should serve as a high-performance task controller that is able to handle documentation and precision agriculture tasks, such as section control. We tested seven Isobus-ready tractors.
The basic signals
The tractor uses an ECU to transmit a signal from the CAN bus to the implement, for example travel speed based on rotating wheels and a radar signal, PTO speed and activation, lifting height, etc.
In accordance with the ISO 11783 standard, a tractor ECU may fulfill the requirements of class 1, 2 or 3, differing only in the number of available signals. The minimum class is 1 (Claas), while most tractors support class 2, which communicates tractive power (sensor on the lifting mechanism) and the status of electronic hydraulic valves in addition to the basic signals.
Class 3 signals
New Holland and Case IH have class 3, enabling the implement to operate some of the tractor’s functions, such as the lifting mechanism or hydraulic valves. With Case IH, this option costs € 763, plus another € 379 if the implement also controls the steering wheel. Unfortunately, we were unable to test the class 3 signals, as this requires special decoupling between the tractor and implement manufacturers, which was not available.
Sensor missing
The signal emitted by the tractor ECU consists of a data packet. The test showed that all tractors transmit that data effectively, but some data is defined as ‘not available’. That means that a sensor is missing. This happens mainly in relation to travel speed, when this signal indicates that there is no radar available in order to determine wheel slip.
To give an example: while the Deutz-Fahr has a correct radar signal, the data is copied one-for-one from the wheel rotation speed and this is not accurate. Meanwhile, in the MF the radar speed is transmitted, but it is non-zero (infinitely small). The speed radar only works as expected in the Claas and Valtra.
The front linkage of the John Deere also has an incorrect digital scale, which runs from 0 to 40% instead of up to 100%. These kinds of errors make it difficult to blindly trust the Isobus.
Isobus integration
The best known Isobus functionality is UT or Universal Terminal (previously VT or Virtual Terminal). This is used by the implement to load its own interface into the terminal. We succeeded in loading the interface from various implements into each of the seven displays without any problem.
However, we identified considerable differences in the way in which the manufacturer integrates the Isobus. Integration in Deutz-Fahr, with a state-of-the-art Topcon display, is hardly what you would call neat. Isobus settings are found under a different main menu to the normal tractor settings. Apart from this, the well-designed display is really comfortable to work with.
John Deere seamlessly integrates Isobus
John Deere is the other extreme, as the Isobus UT has been seamlessly integrated. Claas still regards Isobus as an optional extra, as it supplies a large touchscreen for settings such as transmission and hydraulics, but (still) without Isobus. To include this, you need an additional display mounted on the C-pillar, and the GPS has to run there too. The UT screen opens as a pop-up window in the display above the GPS data. If you use both at the same time, you will need to minimise the Isobus screen to one corner of the map view.
Valtra and Massey Ferguson have tried to achieve the same integration as John Deere, but were not quite as successful. Switching between the Isobus UT and the tractor control unit is more difficult. John Deere makes a joystick use of tabs (like on a smartphone). You can swipe them, but there are also physical buttons.
In the Valtra, you have to press ‘back’ first and select the right screen again, or divide the display into four (small) quadrants. In the MF you do this by swiping across, as with a smartphone, but there are no buttons.
Cumbersome displays in New Holland and Case IH
The displays in the New Holland and Case IH are relatively cumbersome. You can only find the Isobus screen by searching for the right run screen. However, you can rename this tab to make it easier to find again.
After our test, both tractors were updated with a shortcut menu. The manufacturers claim that this will improve accessibility. Ask your dealer about upgrading your Quick Access Menu.
Control using physical buttons
Imagine that you’re using an Isobus-compatible implement and GPS, for a task such as spreading artificial fertiliser. The Isobus screen needs to be active and displayed in order to operate the sprayer. But you also want a map view, and that’s where the Isobus AUX is useful.
It means you can operate the machine using buttons in the tractor or using an extra universal joystick, and you still have the GPS map in front of you. The tractor needs two functions: firstly, the Isobus display must include an AUX configuration screen. Secondly, those physical buttons (e.g., as on the drive joystick) must be freely programmable and assignable to AUX.
Two AUV versions
All test tractors were capable of doing either one or both of these operations. Unfortunately, there are two versions: AUX-N (new) and AUX-O (old), and the tractor and implement both need to have the same version. Deutz-Fahr only offers AUX-N. The buttons on the drive joystick work with the Isobus, and there is a configuration screen to allow them to be assigned.
Claas only had AUX-O at the time of testing; the Axion now features both AUX-N and AUX-O. The numerous buttons on the drive joystick are freely programmable and there is a configuration screen. Valtra and MF now also feature both AUX-O and AUX-N as a result of a recent update.
Valtra unable to link Isobus functions to drive joystick
When testing, Valtra was unable to link any Isobus functions to the drive joystick; this has since been fixed. The display features a configuration menu, so it is possible to link to an extra universal joystick. Massey Ferguson allows some buttons on the drive joystick to be linked, but we failed to make it work, despite several attempts.
New Holland and Case IH have AUX-N, and it is possible to assign physical buttons to an implement. This is, incidentally, by far the most difficult thing to do in these tractors, because you need different tabs in the right order. Configuration is easy in the John Deere. You can, however, save different configurations to different user profiles.
