Frank Felten

November 14, 2023
3 minutes read

Presenting the ZF Health Check

Predictive maintenance for Ecolife transmissions – How does it work?

In summer 2023, ZF launched a digital service called ZF Health Check that enables the condition of ZF components to be monitored during operation. Our first candidate for this was the ZF Ecolife transmission, which is widely used in the bus vehicle segment and is installed as standard by many manufacturers.


Buses are the backbone of local public transport and an essential component of sustainable mobility. However, ensuring efficient and reliable bus operation is a challenge given the demanding conditions under which these vehicles are operated. This is why predictive maintenance for buses makes a lot of sense and quickly pays for itself. With the Health Check, ZF retrieves data from the vehicle on a daily basis, analyses it automatically and generates recommendations for optimum operation. This information is made available via the ZF Bus Connect telematics solution.

The level of detail of the information varies depending on whether the addressee is the service planner of a public transport company, who is primarily interested in basic operational capability, or the highly specialised ZF service partner, who can draw conclusions from the information about necessary maintenance activities or spare parts requirements without having to have the bus in the workshop physically.

Which data is included?

The Ecolife transmission health check is mainly based on internal transmission parameters and statistics. These are either retrieved directly from sensors in the transmission or are based on software-controlled variables. The large number of available measured values (several hundred) illustrates the complexity of the system. For supplementary analyses, we rely on other vehicle signals such as engine speed, coolant temperature and potential error messages from networked systems, which are available via the vehicle's CAN bus and often also via the FMS interface.

Which variance does this bring into maintenance cycles?

This varies from case to case and also depends on how the vehicle is used. This is precisely the advantage of a permanent condition monitoring system: it alerts the user to anomalies (e.g. increased oil temperature) that could potentially lead to problems. By checking the vehicle preventively, the vehicle owner can thus avoid damage. However, if no anomalies or problems are detected, the fleet manager or workshop manager can establish a correlation between the recommended interval and extension of the maintenance cycles and be confident that the system is being continuously monitored.

bus gearbox

What are typical problems that can be recognized beforehand?

A typical issue is the wear of the clutch packs in the transmission, which are crucial for smooth operation. By using advanced algorithms, we can estimate the wear of these clutches very well and predict potential failures. This allows the fleet manager to determine the optimum time for planned preventive maintenance. This avoids expensive breakdowns which - if they happen undetected during operation - lead to high follow-up costs and frustration for passengers and transport companies.

And what about artificial intelligence?

Wherever a lot of data is handled, artificial intelligence will sooner or later become an issue. The ZF Health Check does not yet use artificial intelligence, but is based on the unique vehicle expertise and many years of experience of the ZF experts, which has been moulded into algorithms. The quality of artificial intelligence stands and falls with the amount of available training data for corresponding AI models. Only those who can read from millions of data records on all possible operating states, environmental parameters and, in particular, subsequent events (damage, breakdowns, workshop visits) will achieve a good model. With its large installed base and global network of service partners, ZF is well positioned for this - the time for artificial intelligence will dawn, but as long as large quantities of training data still need to be collected, human intelligence is the current tool of choice.


What's next?

Following the market launch in mid-2023, ZF is currently gathering in-depth feedback from the first customers (innovators) with the aim of further increasing the benefits of the program for the various users - for example through even better proactive notifications. Plans are also underway to include further vehicle components in the Health Check in order to gradually develop it into a module that ensures greater vehicle availability through proactive action.

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