Scania ZF DTC 4421 Proportional valve D1

ZF ZF gearbox · Scania

Code 4421 (decimal). Some diagnostic tools show it in hexadecimal as 1145.

In short

Incorrect signal from proportional valve D1.

Applies to: ZF1

What does Scania ZF fault code 4421 mean?

What causes Scania DTC 4421?

How does the system react?

How to fix Scania ZF fault code 4421?

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This information is for guidance only. Always follow the manufacturer workshop manual and safety procedures; if in doubt, contact an authorised workshop.

Code 4421 in other Scania systems

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