Scania ALLISON DTC 9840 Actuator for supply voltage (HSD2), low

ALLISON Allison automatic gearbox · Scania

Code 9840 (decimal). Some diagnostic tools show it in hexadecimal as 2670.

In short

The control unit has detected less than 6 V in three solenoids in the HSD2 circuit.

Applies to: A4

What does Scania ALLISON fault code 9840 mean?

What causes Scania DTC 9840?

How does the system react?

How to fix Scania ALLISON fault code 9840?

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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.