Scania EMU DTC 4172 Heater H39, secondary transistor, electrical fault

EMU EMU control unit · Scania

Code 4172 (decimal). Some diagnostic tools show it in hexadecimal as 00104C.

In short

The control system has measured current of over 500 mA while the PWM signal to both heating elements is low.

Applies to: EMU1 (ECS)

What does Scania EMU fault code 4172 mean?

What causes Scania DTC 4172?

How does the system react?

What are the symptoms?

How to fix Scania EMU fault code 4172?

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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.

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