Scania VDT DTC 121 Gearbox identification unit

VDT VDT control unit · Scania

Code 121 (decimal). Some diagnostic tools show it in hexadecimal as 0079.

In short

Signal fault from identification unit.

Applies to: VDT2 (VDT)

What does Scania VDT fault code 121 mean?

What causes Scania DTC 121?

How does the system react?

How to fix Scania VDT fault code 121?

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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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